From 8975e16a6e5a03e8b7bc27f7e0adbaa04b61831f Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Wed, 18 Sep 2024 15:43:46 +0200
Subject: [PATCH 01/24] WIP: userland files validation

---
 .../StarterTemplates/Templating.hs            |  3 +-
 waspc/src/Wasp/AppSpec.hs                     |  2 +-
 waspc/src/Wasp/AppSpec/PackageJson.hs         | 25 ------
 waspc/src/Wasp/ExternalConfig.hs              | 31 +++++++
 waspc/src/Wasp/ExternalConfig/PackageJson.hs  | 88 +++++++++++++++++++
 waspc/src/Wasp/ExternalConfig/TsConfig.hs     | 62 +++++++++++++
 waspc/src/Wasp/Generator/NpmDependencies.hs   |  6 +-
 waspc/src/Wasp/Project/Analyze.hs             | 34 ++-----
 waspc/src/Wasp/Project/Common.hs              |  4 +
 waspc/src/Wasp/Util/Json.hs                   | 16 ++++
 waspc/test/AppSpec/ValidTest.hs               | 10 +--
 waspc/test/Generator/WebAppGeneratorTest.hs   | 10 +--
 waspc/waspc.cabal                             |  5 +-
 13 files changed, 229 insertions(+), 67 deletions(-)
 delete mode 100644 waspc/src/Wasp/AppSpec/PackageJson.hs
 create mode 100644 waspc/src/Wasp/ExternalConfig.hs
 create mode 100644 waspc/src/Wasp/ExternalConfig/PackageJson.hs
 create mode 100644 waspc/src/Wasp/ExternalConfig/TsConfig.hs
 create mode 100644 waspc/src/Wasp/Util/Json.hs

diff --git a/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs b/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs
index 146f30660e..13a6ec5061 100644
--- a/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs
+++ b/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs
@@ -9,7 +9,8 @@ import qualified Data.Text as T
 import StrongPath (Abs, Dir, File, Path')
 import Wasp.Cli.Command.CreateNewProject.Common (defaultWaspVersionBounds)
 import Wasp.Cli.Command.CreateNewProject.ProjectDescription (NewProjectAppName, NewProjectName)
-import Wasp.Project.Analyze (findPackageJsonFile, findWaspFile)
+import Wasp.ExternalConfig.PackageJson (findPackageJsonFile)
+import Wasp.Project.Analyze (findWaspFile)
 import Wasp.Project.Common (WaspProjectDir)
 import qualified Wasp.Util.IO as IOUtil
 
diff --git a/waspc/src/Wasp/AppSpec.hs b/waspc/src/Wasp/AppSpec.hs
index f1438fde28..6f5a2d683c 100644
--- a/waspc/src/Wasp/AppSpec.hs
+++ b/waspc/src/Wasp/AppSpec.hs
@@ -42,11 +42,11 @@ import qualified Wasp.AppSpec.ExternalFiles as ExternalFiles
 import Wasp.AppSpec.Job (Job)
 import Wasp.AppSpec.Operation (Operation)
 import qualified Wasp.AppSpec.Operation as AS.Operation
-import Wasp.AppSpec.PackageJson (PackageJson)
 import Wasp.AppSpec.Page (Page)
 import Wasp.AppSpec.Query (Query)
 import Wasp.AppSpec.Route (Route)
 import Wasp.Env (EnvVar)
+import Wasp.ExternalConfig.PackageJson (PackageJson)
 import Wasp.Node.Version (oldestWaspSupportedNodeVersion)
 import Wasp.Project.Common (WaspProjectDir)
 import Wasp.Project.Db.Migrations (DbMigrationsDir)
diff --git a/waspc/src/Wasp/AppSpec/PackageJson.hs b/waspc/src/Wasp/AppSpec/PackageJson.hs
deleted file mode 100644
index cc90def775..0000000000
--- a/waspc/src/Wasp/AppSpec/PackageJson.hs
+++ /dev/null
@@ -1,25 +0,0 @@
-{-# LANGUAGE DeriveGeneric #-}
-
-module Wasp.AppSpec.PackageJson where
-
-import Data.Aeson (FromJSON)
-import Data.Map (Map)
-import qualified Data.Map as M
-import GHC.Generics (Generic)
-import Wasp.AppSpec.App.Dependency (Dependency)
-import qualified Wasp.AppSpec.App.Dependency as D
-
-data PackageJson = PackageJson
-  { name :: !String,
-    dependencies :: !(Map String String),
-    devDependencies :: !(Map String String)
-  }
-  deriving (Show, Generic)
-
-instance FromJSON PackageJson
-
-getDependencies :: PackageJson -> [Dependency]
-getDependencies packageJson = D.fromList $ M.toList $ dependencies packageJson
-
-getDevDependencies :: PackageJson -> [Dependency]
-getDevDependencies packageJson = D.fromList $ M.toList $ devDependencies packageJson
diff --git a/waspc/src/Wasp/ExternalConfig.hs b/waspc/src/Wasp/ExternalConfig.hs
new file mode 100644
index 0000000000..b426b5cbd1
--- /dev/null
+++ b/waspc/src/Wasp/ExternalConfig.hs
@@ -0,0 +1,31 @@
+module Wasp.ExternalConfig
+  ( ExternalConfigs (..),
+    analyzeExternalConfigs,
+  )
+where
+
+import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
+import StrongPath (Abs, Dir, Path')
+import Wasp.ExternalConfig.PackageJson (PackageJson, analyzePackageJsonContent)
+import Wasp.ExternalConfig.TsConfig (TsConfig, analyzeTsConfigContent)
+import Wasp.Project.Common
+  ( CompileError,
+    WaspProjectDir,
+  )
+
+data ExternalConfigs = ExternalConfigs
+  { packageJson :: PackageJson,
+    tsConfig :: TsConfig
+  }
+  deriving (Show)
+
+analyzeExternalConfigs :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] ExternalConfigs)
+analyzeExternalConfigs waspDir = runExceptT $ do
+  packageJsonContent <- ExceptT $ analyzePackageJsonContent waspDir
+  tsConfigContent <- ExceptT $ analyzeTsConfigContent waspDir
+
+  return $
+    ExternalConfigs
+      { packageJson = packageJsonContent,
+        tsConfig = tsConfigContent
+      }
diff --git a/waspc/src/Wasp/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
new file mode 100644
index 0000000000..6aef01865a
--- /dev/null
+++ b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
@@ -0,0 +1,88 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Wasp.ExternalConfig.PackageJson
+  ( PackageJson (..),
+    getDependencies,
+    getDevDependencies,
+    analyzePackageJsonContent,
+    findPackageJsonFile,
+  )
+where
+
+import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
+import Data.Aeson (FromJSON)
+import qualified Data.Aeson as Aeson
+import Data.Map (Map)
+import qualified Data.Map as M
+import GHC.Generics (Generic)
+import StrongPath (Abs, Dir, File', Path', toFilePath)
+import Wasp.AppSpec.App.Dependency (Dependency)
+import qualified Wasp.AppSpec.App.Dependency as D
+import Wasp.Project.Common
+  ( CompileError,
+    WaspProjectDir,
+    findFileInWaspProjectDir,
+    packageJsonInWaspProjectDir,
+  )
+import Wasp.Util (maybeToEither)
+import qualified Wasp.Util.IO as IOUtil
+
+data PackageJson = PackageJson
+  { name :: !String,
+    dependencies :: !DependenciesMap,
+    devDependencies :: !DependenciesMap
+  }
+  deriving (Show, Generic)
+
+type DependenciesMap = Map PackageName PackageVersion
+
+type PackageName = String
+
+type PackageVersion = String
+
+instance FromJSON PackageJson
+
+analyzePackageJsonContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] PackageJson)
+analyzePackageJsonContent waspProjectDir = runExceptT $ do
+  packageJsonFile <- ExceptT findPackageJsonFileOrError
+  packageJson <- ExceptT $ readPackageJsonFile packageJsonFile
+  ExceptT $ validatePackageJson packageJson
+  where
+    findPackageJsonFileOrError = maybeToEither [fileNotFoundMessage] <$> findPackageJsonFile waspProjectDir
+    fileNotFoundMessage = "Couldn't find the package.json file in the " ++ toFilePath waspProjectDir ++ " directory"
+
+validatePackageJson :: PackageJson -> IO (Either [CompileError] PackageJson)
+validatePackageJson packageJson =
+  return $
+    if null packageJsonErrors
+      then Right packageJson
+      else Left packageJsonErrors
+  where
+    packageJsonErrors =
+      validatePackageInDeps (dependencies packageJson) ("wasp", "file:.wasp/out/sdk/wasp")
+
+findPackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs File'))
+findPackageJsonFile waspProjectDir = findFileInWaspProjectDir waspProjectDir packageJsonInWaspProjectDir
+
+readPackageJsonFile :: Path' Abs File' -> IO (Either [CompileError] PackageJson)
+readPackageJsonFile packageJsonFile = do
+  byteString <- IOUtil.readFileBytes packageJsonFile
+  return $ maybeToEither ["Error parsing the package.json file"] $ Aeson.decode byteString
+
+validatePackageInDeps :: DependenciesMap -> (PackageName, PackageVersion) -> [CompileError]
+validatePackageInDeps deps (packageName, expectedPackageVersion) =
+  case M.lookup packageName deps of
+    Just actualPackageVersion ->
+      if actualPackageVersion == expectedPackageVersion
+        then []
+        else [packageVersionMismatchMessage]
+    Nothing -> [packageNotFoundMessage]
+  where
+    packageVersionMismatchMessage = "The package \"" ++ packageName ++ "\" is not the expected version \"" ++ expectedPackageVersion ++ "\"."
+    packageNotFoundMessage = "The package \"" ++ packageName ++ "\" is not found in the dependencies."
+
+getDependencies :: PackageJson -> [Dependency]
+getDependencies packageJson = D.fromList $ M.toList $ dependencies packageJson
+
+getDevDependencies :: PackageJson -> [Dependency]
+getDevDependencies packageJson = D.fromList $ M.toList $ devDependencies packageJson
diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
new file mode 100644
index 0000000000..89d73d190a
--- /dev/null
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -0,0 +1,62 @@
+{-# LANGUAGE DeriveGeneric #-}
+
+module Wasp.ExternalConfig.TsConfig
+  ( TsConfig (..),
+    analyzeTsConfigContent,
+  )
+where
+
+import Control.Monad.Except
+import Data.Aeson (FromJSON)
+import qualified Data.ByteString.Lazy.UTF8 as BS
+import Data.Either.Extra (maybeToEither)
+import GHC.Generics (Generic)
+import StrongPath (Abs, Dir, File', Path', toFilePath)
+import Wasp.Project.Common
+  ( CompileError,
+    WaspProjectDir,
+    findFileInWaspProjectDir,
+    tsConfigInWaspProjectDir,
+  )
+import qualified Wasp.Util.IO as IOUtil
+import Wasp.Util.Json (parseJsonWithComments)
+
+data TsConfig = TsConfig
+  { compilerOptions :: !CompilerOptions
+  }
+  deriving (Show, Generic)
+
+instance FromJSON TsConfig
+
+data CompilerOptions = CompilerOptions
+  { target :: !String
+  }
+  deriving (Show, Generic)
+
+instance FromJSON CompilerOptions
+
+analyzeTsConfigContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] TsConfig)
+analyzeTsConfigContent waspDir = runExceptT $ do
+  tsConfigFile <- ExceptT findTsConfigOrError
+  tsConfig <- ExceptT $ showTsConfig tsConfigFile
+  ExceptT $ validateTsConfig tsConfig
+  where
+    findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
+    fileNotFoundMessage = "Couldn't find the tsconfig.json file in the " ++ toFilePath waspDir ++ " directory"
+
+findTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs File'))
+findTsConfigFile waspProjectDir = findFileInWaspProjectDir waspProjectDir tsConfigInWaspProjectDir
+
+showTsConfig :: Path' Abs File' -> IO (Either [CompileError] TsConfig)
+showTsConfig tsConfigFile = do
+  tsConfigContent <- BS.toString <$> IOUtil.readFileBytes tsConfigFile
+
+  parseResult <- parseJsonWithComments tsConfigContent
+
+  case parseResult of
+    Right tsConfig -> return $ Right tsConfig
+    Left err -> return $ Left [err]
+
+-- TODO: validate config fields
+validateTsConfig :: TsConfig -> IO (Either [CompileError] TsConfig)
+validateTsConfig tsConfig = return $ Right tsConfig
diff --git a/waspc/src/Wasp/Generator/NpmDependencies.hs b/waspc/src/Wasp/Generator/NpmDependencies.hs
index c341ee2ed4..7d937c7d03 100644
--- a/waspc/src/Wasp/Generator/NpmDependencies.hs
+++ b/waspc/src/Wasp/Generator/NpmDependencies.hs
@@ -25,7 +25,7 @@ import GHC.Generics
 import Wasp.AppSpec (AppSpec)
 import qualified Wasp.AppSpec as AS
 import qualified Wasp.AppSpec.App.Dependency as D
-import qualified Wasp.AppSpec.PackageJson as AS.PackageJson
+import qualified Wasp.ExternalConfig.PackageJson as EC.PackageJson
 import Wasp.Generator.Monad (Generator, GeneratorError (..), logAndThrowGeneratorError)
 
 data NpmDepsForFramework = NpmDepsForFramework
@@ -110,9 +110,9 @@ buildWaspFrameworkNpmDeps spec forServer forWebApp =
 getUserNpmDepsForPackage :: AppSpec -> NpmDepsForUser
 getUserNpmDepsForPackage spec =
   NpmDepsForUser
-    { userDependencies = AS.PackageJson.getDependencies $ AS.packageJson spec,
+    { userDependencies = EC.PackageJson.getDependencies $ AS.packageJson spec,
       -- Should we allow user devDependencies? https://github.com/wasp-lang/wasp/issues/456
-      userDevDependencies = AS.PackageJson.getDevDependencies $ AS.packageJson spec
+      userDevDependencies = EC.PackageJson.getDevDependencies $ AS.packageJson spec
     }
 
 conflictErrorToMessage :: DependencyConflictError -> String
diff --git a/waspc/src/Wasp/Project/Analyze.hs b/waspc/src/Wasp/Project/Analyze.hs
index 3cccb0856b..e7e5ece230 100644
--- a/waspc/src/Wasp/Project/Analyze.hs
+++ b/waspc/src/Wasp/Project/Analyze.hs
@@ -1,34 +1,30 @@
 module Wasp.Project.Analyze
   ( analyzeWaspProject,
-    readPackageJsonFile,
     analyzeWaspFileContent,
     findWaspFile,
-    findPackageJsonFile,
     analyzePrismaSchema,
   )
 where
 
 import Control.Arrow (ArrowChoice (left))
-import qualified Data.Aeson as Aeson
 import Data.List (find, isSuffixOf)
 import StrongPath (Abs, Dir, File', Path', toFilePath, (</>))
 import qualified Wasp.Analyzer as Analyzer
 import Wasp.Analyzer.AnalyzeError (getErrorMessageAndCtx)
 import Wasp.Analyzer.Parser.Ctx (Ctx)
 import qualified Wasp.AppSpec as AS
-import Wasp.AppSpec.PackageJson (PackageJson)
 import qualified Wasp.AppSpec.Valid as ASV
 import Wasp.CompileOptions (CompileOptions)
 import qualified Wasp.CompileOptions as CompileOptions
 import qualified Wasp.ConfigFile as CF
 import Wasp.Error (showCompilerErrorForTerminal)
+import qualified Wasp.ExternalConfig as EC
 import qualified Wasp.Generator.ConfigFile as G.CF
 import Wasp.Project.Common
   ( CompileError,
     CompileWarning,
     WaspProjectDir,
     findFileInWaspProjectDir,
-    packageJsonInWaspProjectDir,
     prismaSchemaFileInWaspProjectDir,
   )
 import Wasp.Project.Db (makeDevDatabaseUrl)
@@ -63,9 +59,9 @@ analyzeWaspProject waspDir options = do
           analyzeWaspFile prismaSchemaAst waspFilePath >>= \case
             Left errors -> return (Left errors, [])
             Right declarations ->
-              analyzePackageJsonContent waspDir >>= \case
+              EC.analyzeExternalConfigs waspDir >>= \case
                 Left errors -> return (Left errors, [])
-                Right packageJsonContent -> constructAppSpec waspDir options packageJsonContent prismaSchemaAst declarations
+                Right externalConfigs -> constructAppSpec waspDir options externalConfigs prismaSchemaAst declarations
   where
     fileNotFoundMessage = "Couldn't find the *.wasp file in the " ++ toFilePath waspDir ++ " directory"
 
@@ -81,11 +77,11 @@ analyzeWaspFileContent prismaSchemaAst = return . left (map getErrorMessageAndCt
 constructAppSpec ::
   Path' Abs (Dir WaspProjectDir) ->
   CompileOptions ->
-  PackageJson ->
+  EC.ExternalConfigs ->
   Psl.Schema.Schema ->
   [AS.Decl] ->
   IO (Either [CompileError] AS.AppSpec, [CompileWarning])
-constructAppSpec waspDir options packageJson parsedPrismaSchema decls = do
+constructAppSpec waspDir options externalConfigs parsedPrismaSchema decls = do
   externalCodeFiles <- ExternalFiles.readCodeFiles waspDir
   externalPublicFiles <- ExternalFiles.readPublicFiles waspDir
   customViteConfigPath <- findCustomViteConfigPath waspDir
@@ -98,11 +94,13 @@ constructAppSpec waspDir options packageJson parsedPrismaSchema decls = do
   serverEnvVars <- readDotEnvServer waspDir
   clientEnvVars <- readDotEnvClient waspDir
 
+  let packageJsonContent = EC.packageJson externalConfigs
+
   let appSpec =
         AS.AppSpec
           { AS.decls = decls,
             AS.prismaSchema = parsedPrismaSchema,
-            AS.packageJson = packageJson,
+            AS.packageJson = packageJsonContent,
             AS.waspProjectDir = waspDir,
             AS.externalCodeFiles = externalCodeFiles,
             AS.externalPublicFiles = externalPublicFiles,
@@ -128,22 +126,6 @@ findWaspFile waspDir = do
         `isSuffixOf` toFilePath path
         && (length (toFilePath path) > length (".wasp" :: String))
 
-analyzePackageJsonContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] PackageJson)
-analyzePackageJsonContent waspProjectDir =
-  findPackageJsonFile waspProjectDir >>= \case
-    Just packageJsonFile -> readPackageJsonFile packageJsonFile
-    Nothing -> return $ Left [fileNotFoundMessage]
-  where
-    fileNotFoundMessage = "Couldn't find the package.json file in the " ++ toFilePath waspProjectDir ++ " directory"
-
-findPackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs File'))
-findPackageJsonFile waspProjectDir = findFileInWaspProjectDir waspProjectDir packageJsonInWaspProjectDir
-
-readPackageJsonFile :: Path' Abs File' -> IO (Either [CompileError] PackageJson)
-readPackageJsonFile packageJsonFile = do
-  byteString <- IOUtil.readFileBytes packageJsonFile
-  return $ maybeToEither ["Error parsing the package.json file"] $ Aeson.decode byteString
-
 analyzePrismaSchema :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] Psl.Schema.Schema, [CompileWarning])
 analyzePrismaSchema waspProjectDir = do
   findPrismaSchemaFile waspProjectDir >>= \case
diff --git a/waspc/src/Wasp/Project/Common.hs b/waspc/src/Wasp/Project/Common.hs
index 2de89f27a0..993c969634 100644
--- a/waspc/src/Wasp/Project/Common.hs
+++ b/waspc/src/Wasp/Project/Common.hs
@@ -18,6 +18,7 @@ module Wasp.Project.Common
     extPublicDirInWaspProjectDir,
     tsconfigInWaspProjectDir,
     prismaSchemaFileInWaspProjectDir,
+    tsConfigInWaspProjectDir,
   )
 where
 
@@ -69,6 +70,9 @@ dotWaspInfoFileInGeneratedCodeDir = [relfile|.waspinfo|]
 packageJsonInWaspProjectDir :: Path' (Rel WaspProjectDir) File'
 packageJsonInWaspProjectDir = [relfile|package.json|]
 
+tsConfigInWaspProjectDir :: Path' (Rel WaspProjectDir) File'
+tsConfigInWaspProjectDir = [relfile|tsconfig.json|]
+
 packageLockJsonInWaspProjectDir :: Path' (Rel WaspProjectDir) File'
 packageLockJsonInWaspProjectDir = [relfile|package-lock.json|]
 
diff --git a/waspc/src/Wasp/Util/Json.hs b/waspc/src/Wasp/Util/Json.hs
new file mode 100644
index 0000000000..aa43e655c6
--- /dev/null
+++ b/waspc/src/Wasp/Util/Json.hs
@@ -0,0 +1,16 @@
+module Wasp.Util.Json (parseJsonWithComments) where
+
+import Data.Aeson (FromJSON)
+import System.Exit (ExitCode (..))
+import qualified System.Process as P
+import Wasp.Util.Aeson (decodeFromString)
+
+-- | Uses Node.js to parse JSON with comments by treating it as a JavaScript object.
+parseJsonWithComments :: FromJSON a => String -> IO (Either String a)
+parseJsonWithComments jsonStr = do
+  let evalScript = "const v = " ++ jsonStr ++ ";console.log(JSON.stringify(v));"
+  let cp = P.proc "node" ["-e", evalScript]
+  (exitCode, response, stderr) <- P.readCreateProcessWithExitCode cp ""
+  case exitCode of
+    ExitSuccess -> return $ decodeFromString response
+    _exitFailure -> return $ Left stderr
diff --git a/waspc/test/AppSpec/ValidTest.hs b/waspc/test/AppSpec/ValidTest.hs
index 7859f655ce..d61908c6fc 100644
--- a/waspc/test/AppSpec/ValidTest.hs
+++ b/waspc/test/AppSpec/ValidTest.hs
@@ -26,11 +26,11 @@ import qualified Wasp.AppSpec.Crud as AS.Crud
 import qualified Wasp.AppSpec.Entity as AS.Entity
 import qualified Wasp.AppSpec.ExtImport as AS.ExtImport
 import qualified Wasp.AppSpec.Job as AS.Job
-import qualified Wasp.AppSpec.PackageJson as AS.PJS
 import qualified Wasp.AppSpec.Page as AS.Page
 import qualified Wasp.AppSpec.Query as AS.Query
 import qualified Wasp.AppSpec.Route as AS.Route
 import qualified Wasp.AppSpec.Valid as ASV
+import qualified Wasp.ExternalConfig.PackageJson as EC.PackageJson
 import qualified Wasp.Psl.Ast.Attribute as Psl.Attribute
 import qualified Wasp.Psl.Ast.Model as Psl.Model
 import qualified Wasp.SemanticVersion as SV
@@ -448,10 +448,10 @@ spec_AppSpecValid = do
           AS.externalCodeFiles = [],
           AS.externalPublicFiles = [],
           AS.packageJson =
-            AS.PJS.PackageJson
-              { AS.PJS.name = "testApp",
-                AS.PJS.dependencies = M.empty,
-                AS.PJS.devDependencies = M.empty
+            EC.PackageJson.PackageJson
+              { EC.PackageJson.name = "testApp",
+                EC.PackageJson.dependencies = M.empty,
+                EC.PackageJson.devDependencies = M.empty
               },
           AS.isBuild = False,
           AS.migrationsDir = Nothing,
diff --git a/waspc/test/Generator/WebAppGeneratorTest.hs b/waspc/test/Generator/WebAppGeneratorTest.hs
index 65feece08a..72614b05f5 100644
--- a/waspc/test/Generator/WebAppGeneratorTest.hs
+++ b/waspc/test/Generator/WebAppGeneratorTest.hs
@@ -9,7 +9,7 @@ import qualified Wasp.AppSpec as AS
 import qualified Wasp.AppSpec.App as AS.App
 import qualified Wasp.AppSpec.App.Wasp as AS.Wasp
 import qualified Wasp.AppSpec.Core.Decl as AS.Decl
-import qualified Wasp.AppSpec.PackageJson as AS.PJS
+import qualified Wasp.ExternalConfig.PackageJson as EC.PackageJson
 import Wasp.Generator.FileDraft
 import qualified Wasp.Generator.FileDraft.CopyAndModifyTextFileDraft as CMTextFD
 import qualified Wasp.Generator.FileDraft.CopyDirFileDraft as CopyDirFD
@@ -52,10 +52,10 @@ spec_WebAppGenerator = do
             AS.externalCodeFiles = [],
             AS.externalPublicFiles = [],
             AS.packageJson =
-              AS.PJS.PackageJson
-                { AS.PJS.name = "testApp",
-                  AS.PJS.dependencies = M.empty,
-                  AS.PJS.devDependencies = M.empty
+              EC.PackageJson.PackageJson
+                { EC.PackageJson.name = "testApp",
+                  EC.PackageJson.dependencies = M.empty,
+                  EC.PackageJson.devDependencies = M.empty
                 },
             AS.isBuild = False,
             AS.migrationsDir = Nothing,
diff --git a/waspc/waspc.cabal b/waspc/waspc.cabal
index 244521b37f..33b82e7764 100644
--- a/waspc/waspc.cabal
+++ b/waspc/waspc.cabal
@@ -248,7 +248,6 @@ library
     Wasp.AppSpec.Job
     Wasp.AppSpec.JSON
     Wasp.AppSpec.Operation
-    Wasp.AppSpec.PackageJson
     Wasp.AppSpec.Page
     Wasp.AppSpec.Query
     Wasp.AppSpec.Route
@@ -260,6 +259,9 @@ library
     Wasp.Db.Postgres
     Wasp.Error
     Wasp.Env
+    Wasp.ExternalConfig
+    Wasp.ExternalConfig.PackageJson
+    Wasp.ExternalConfig.TsConfig
     Wasp.Generator
     Wasp.Generator.AuthProviders
     Wasp.Generator.AuthProviders.Common
@@ -408,6 +410,7 @@ library
     Wasp.Util.HashMap
     Wasp.Util.IO
     Wasp.Util.IO.Retry
+    Wasp.Util.Json
     Wasp.Util.Network.HTTP
     Wasp.Util.Network.Socket
     Wasp.Util.Terminal

From 3854e185fc7c105be34a67052a3e4941eef2de26 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Wed, 18 Sep 2024 15:47:48 +0200
Subject: [PATCH 02/24] Cleanup

---
 waspc/src/Wasp/ExternalConfig/TsConfig.hs | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index 89d73d190a..cd382b4d7a 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -28,6 +28,7 @@ data TsConfig = TsConfig
 
 instance FromJSON TsConfig
 
+-- TODO: define fields we want to validate
 data CompilerOptions = CompilerOptions
   { target :: !String
   }
@@ -38,7 +39,7 @@ instance FromJSON CompilerOptions
 analyzeTsConfigContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] TsConfig)
 analyzeTsConfigContent waspDir = runExceptT $ do
   tsConfigFile <- ExceptT findTsConfigOrError
-  tsConfig <- ExceptT $ showTsConfig tsConfigFile
+  tsConfig <- ExceptT $ readTsConfigFile tsConfigFile
   ExceptT $ validateTsConfig tsConfig
   where
     findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
@@ -47,11 +48,11 @@ analyzeTsConfigContent waspDir = runExceptT $ do
 findTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs File'))
 findTsConfigFile waspProjectDir = findFileInWaspProjectDir waspProjectDir tsConfigInWaspProjectDir
 
-showTsConfig :: Path' Abs File' -> IO (Either [CompileError] TsConfig)
-showTsConfig tsConfigFile = do
-  tsConfigContent <- BS.toString <$> IOUtil.readFileBytes tsConfigFile
+readTsConfigFile :: Path' Abs File' -> IO (Either [CompileError] TsConfig)
+readTsConfigFile tsConfigFile = do
+  tsConfigContent <- IOUtil.readFileBytes tsConfigFile
 
-  parseResult <- parseJsonWithComments tsConfigContent
+  parseResult <- parseJsonWithComments . BS.toString $ tsConfigContent
 
   case parseResult of
     Right tsConfig -> return $ Right tsConfig

From b0e116f8b5f67329ac1014657bc0fda8dd6f32f1 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Thu, 19 Sep 2024 13:22:27 +0200
Subject: [PATCH 03/24] Upgrade package.json validation

---
 waspc/src/Wasp/ExternalConfig/PackageJson.hs | 65 ++++++++++++++++----
 waspc/src/Wasp/Generator/Common.hs           |  4 ++
 waspc/src/Wasp/Generator/SdkGenerator.hs     |  6 +-
 waspc/src/Wasp/Generator/WebAppGenerator.hs  |  5 +-
 4 files changed, 62 insertions(+), 18 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
index 6aef01865a..e41771dccd 100644
--- a/waspc/src/Wasp/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
@@ -18,6 +18,10 @@ import GHC.Generics (Generic)
 import StrongPath (Abs, Dir, File', Path', toFilePath)
 import Wasp.AppSpec.App.Dependency (Dependency)
 import qualified Wasp.AppSpec.App.Dependency as D
+import Wasp.Generator.Common
+  ( prismaVersion,
+    reactRouterVersion,
+  )
 import Wasp.Project.Common
   ( CompileError,
     WaspProjectDir,
@@ -34,6 +38,12 @@ data PackageJson = PackageJson
   }
   deriving (Show, Generic)
 
+getDependencies :: PackageJson -> [Dependency]
+getDependencies packageJson = D.fromList $ M.toList $ dependencies packageJson
+
+getDevDependencies :: PackageJson -> [Dependency]
+getDevDependencies packageJson = D.fromList $ M.toList $ devDependencies packageJson
+
 type DependenciesMap = Map PackageName PackageVersion
 
 type PackageName = String
@@ -59,7 +69,16 @@ validatePackageJson packageJson =
       else Left packageJsonErrors
   where
     packageJsonErrors =
-      validatePackageInDeps (dependencies packageJson) ("wasp", "file:.wasp/out/sdk/wasp")
+      concat
+        [ -- Wasp needs the Wasp SDK to be installed in the project.
+          validate ("wasp", "file:.wasp/out/sdk/wasp", RequiredPackage),
+          -- Wrong version of Prisma will break the generated code.
+          validate ("prisma", show prismaVersion, RequiredDevPackage),
+          -- Installing the wrong version of "react-router-dom" can make users believe that they
+          -- can use features that are not available in the version that Wasp supports.
+          validate ("react-router-dom", show reactRouterVersion, OptionalPackage)
+        ]
+    validate = validatePackageInDeps packageJson
 
 findPackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs File'))
 findPackageJsonFile waspProjectDir = findFileInWaspProjectDir waspProjectDir packageJsonInWaspProjectDir
@@ -69,20 +88,40 @@ readPackageJsonFile packageJsonFile = do
   byteString <- IOUtil.readFileBytes packageJsonFile
   return $ maybeToEither ["Error parsing the package.json file"] $ Aeson.decode byteString
 
-validatePackageInDeps :: DependenciesMap -> (PackageName, PackageVersion) -> [CompileError]
-validatePackageInDeps deps (packageName, expectedPackageVersion) =
-  case M.lookup packageName deps of
-    Just actualPackageVersion ->
+data PackageValidationType = RequiredPackage | RequiredDevPackage | OptionalPackage
+
+validatePackageInDeps :: PackageJson -> (PackageName, PackageVersion, PackageValidationType) -> [CompileError]
+validatePackageInDeps packageJson (packageName, expectedPackageVersion, validationType) =
+  case map (M.lookup packageName) depsToCheck of
+    (Just actualPackageVersion : _) ->
       if actualPackageVersion == expectedPackageVersion
         then []
-        else [packageVersionMismatchMessage]
-    Nothing -> [packageNotFoundMessage]
+        else [incorrectVersionMessage]
+    _rest -> case validationType of
+      RequiredPackage -> [requiredPackageMessage "dependencies"]
+      RequiredDevPackage -> [requiredPackageMessage "devDependencies"]
+      OptionalPackage -> []
   where
-    packageVersionMismatchMessage = "The package \"" ++ packageName ++ "\" is not the expected version \"" ++ expectedPackageVersion ++ "\"."
-    packageNotFoundMessage = "The package \"" ++ packageName ++ "\" is not found in the dependencies."
+    depsToCheck = case validationType of
+      RequiredPackage -> [dependencies packageJson]
+      RequiredDevPackage -> [devDependencies packageJson]
+      -- Users can install packages that don't need to be strictly in dependencies or devDependencies
+      -- which means Wasp needs to check both to validate the correct version of the package.
+      OptionalPackage -> [dependencies packageJson, devDependencies packageJson]
 
-getDependencies :: PackageJson -> [Dependency]
-getDependencies packageJson = D.fromList $ M.toList $ dependencies packageJson
+    incorrectVersionMessage :: String
+    incorrectVersionMessage =
+      unwords
+        ["The", show packageName, "package must have version", show expectedPackageVersion, "in package.json."]
 
-getDevDependencies :: PackageJson -> [Dependency]
-getDevDependencies packageJson = D.fromList $ M.toList $ devDependencies packageJson
+    requiredPackageMessage :: String -> String
+    requiredPackageMessage packageJsonLocation =
+      unwords
+        [ "The",
+          show packageName,
+          "package with version",
+          show expectedPackageVersion,
+          "must be defined in",
+          show packageJsonLocation,
+          "in package.json."
+        ]
diff --git a/waspc/src/Wasp/Generator/Common.hs b/waspc/src/Wasp/Generator/Common.hs
index 77523b8348..290abcd386 100644
--- a/waspc/src/Wasp/Generator/Common.hs
+++ b/waspc/src/Wasp/Generator/Common.hs
@@ -11,6 +11,7 @@ module Wasp.Generator.Common
     GeneratedSrcDir,
     makeJsArrayFromHaskellList,
     dropExtensionFromImportPath,
+    reactRouterVersion,
   )
 where
 
@@ -57,6 +58,9 @@ prismaVersion :: SV.Version
 --       Then, make sure `data/Generator/templates/sdk/wasp/prisma-runtime-library.d.ts` is up to date.
 prismaVersion = SV.Version 5 19 1
 
+reactRouterVersion :: SV.ComparatorSet
+reactRouterVersion = SV.backwardsCompatibleWith $ SV.Version 5 3 3
+
 makeJsonWithEntityData :: String -> Aeson.Value
 makeJsonWithEntityData name =
   object
diff --git a/waspc/src/Wasp/Generator/SdkGenerator.hs b/waspc/src/Wasp/Generator/SdkGenerator.hs
index 81a5f1f090..c003fa7359 100644
--- a/waspc/src/Wasp/Generator/SdkGenerator.hs
+++ b/waspc/src/Wasp/Generator/SdkGenerator.hs
@@ -26,7 +26,7 @@ import qualified Wasp.AppSpec.App.Dependency as AS.Dependency
 import qualified Wasp.AppSpec.ExternalFiles as EC
 import Wasp.AppSpec.Valid (getLowestNodeVersionUserAllows, isAuthEnabled)
 import qualified Wasp.AppSpec.Valid as AS.Valid
-import Wasp.Generator.Common (ProjectRootDir, makeJsonWithEntityData, prismaVersion)
+import Wasp.Generator.Common (ProjectRootDir, makeJsonWithEntityData, prismaVersion, reactRouterVersion)
 import qualified Wasp.Generator.ConfigFile as G.CF
 import Wasp.Generator.DbGenerator (getEntitiesForPrismaSchema)
 import qualified Wasp.Generator.DbGenerator.Auth as DbAuth
@@ -188,13 +188,13 @@ npmDepsForSdk spec =
             ("mitt", "3.0.0"),
             ("react", "^18.2.0"),
             ("lodash.merge", "^4.6.2"),
-            ("react-router-dom", "^5.3.3"),
+            ("react-router-dom", show reactRouterVersion),
             ("react-hook-form", "^7.45.4"),
             ("superjson", "^1.12.2"),
             -- Todo: why is this in dependencies, should it be in dev dependencies?
             -- Should it go into their package.json
             ("@types/express-serve-static-core", "^4.17.13"),
-            ("@types/react-router-dom", "^5.3.3")
+            ("@types/react-router-dom", show reactRouterVersion)
           ]
           ++ depsRequiredForAuth spec
           ++ depsRequiredByOAuth spec
diff --git a/waspc/src/Wasp/Generator/WebAppGenerator.hs b/waspc/src/Wasp/Generator/WebAppGenerator.hs
index 427e3b905e..9281b50405 100644
--- a/waspc/src/Wasp/Generator/WebAppGenerator.hs
+++ b/waspc/src/Wasp/Generator/WebAppGenerator.hs
@@ -32,6 +32,7 @@ import Wasp.AppSpec.Valid (getApp)
 import Wasp.Env (envVarsToDotEnvContent)
 import Wasp.Generator.Common
   ( makeJsArrayFromHaskellList,
+    reactRouterVersion,
   )
 import Wasp.Generator.FileDraft (FileDraft, createTextFileDraft)
 import qualified Wasp.Generator.FileDraft as FD
@@ -122,7 +123,7 @@ npmDepsForWasp _spec =
             ("react", "^18.2.0"),
             ("react-dom", "^18.2.0"),
             ("@tanstack/react-query", "^4.29.0"),
-            ("react-router-dom", "^5.3.3"),
+            ("react-router-dom", show reactRouterVersion),
             ("superjson", "^1.12.2"),
             ("mitt", "3.0.0"),
             -- Used for Auth UI
@@ -135,7 +136,7 @@ npmDepsForWasp _spec =
             ("typescript", "^5.1.0"),
             ("@types/react", "^18.0.37"),
             ("@types/react-dom", "^18.0.11"),
-            ("@types/react-router-dom", "^5.3.3"),
+            ("@types/react-router-dom", show reactRouterVersion),
             ("@vitejs/plugin-react", "^4.2.1"),
             ("dotenv", "^16.0.3"),
             -- NOTE: Make sure to bump the version of the tsconfig

From 9b21447bb2a6fccefe7993273cc52b0b0f0a67d1 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Thu, 19 Sep 2024 14:07:21 +0200
Subject: [PATCH 04/24] Tsconfig validation WIP

---
 waspc/examples/todoApp/tsconfig.json      |  10 +-
 waspc/src/Wasp/ExternalConfig/TsConfig.hs | 111 ++++++++++++++++++++--
 waspc/src/Wasp/Generator/SdkGenerator.hs  |   5 +-
 3 files changed, 111 insertions(+), 15 deletions(-)

diff --git a/waspc/examples/todoApp/tsconfig.json b/waspc/examples/todoApp/tsconfig.json
index 4932b229a0..75adcc205d 100644
--- a/waspc/examples/todoApp/tsconfig.json
+++ b/waspc/examples/todoApp/tsconfig.json
@@ -15,11 +15,11 @@
     "strict": true,
     // Allow default imports.
     "esModuleInterop": true,
-    "lib": [
-      "dom",
-      "dom.iterable",
-      "esnext"
-    ],
+    // "lib": [
+    //   "dom",
+    //   "dom.iterable",
+    //   "esnext"
+    // ],
     "allowJs": true,
     "typeRoots": [
       // This is needed to properly support Vitest testing with jest-dom matchers.
diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index cd382b4d7a..c289b30b1d 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -1,4 +1,7 @@
 {-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE InstanceSigs #-}
+{-# LANGUAGE TypeSynonymInstances #-}
 
 module Wasp.ExternalConfig.TsConfig
   ( TsConfig (..),
@@ -7,9 +10,10 @@ module Wasp.ExternalConfig.TsConfig
 where
 
 import Control.Monad.Except
-import Data.Aeson (FromJSON)
+import Data.Aeson (FromJSON, parseJSON, withObject, (.:?))
 import qualified Data.ByteString.Lazy.UTF8 as BS
 import Data.Either.Extra (maybeToEither)
+import qualified Data.Map as M
 import GHC.Generics (Generic)
 import StrongPath (Abs, Dir, File', Path', toFilePath)
 import Wasp.Project.Common
@@ -28,18 +32,40 @@ data TsConfig = TsConfig
 
 instance FromJSON TsConfig
 
--- TODO: define fields we want to validate
 data CompilerOptions = CompilerOptions
-  { target :: !String
+  { _module :: !(Maybe String),
+    target :: !(Maybe String),
+    moduleResolution :: !(Maybe String),
+    jsx :: !(Maybe String),
+    strict :: !(Maybe Bool),
+    esModuleInterop :: !(Maybe Bool),
+    lib :: !(Maybe [String]),
+    allowJs :: !(Maybe Bool),
+    typeRoots :: !(Maybe [String]),
+    outDir :: !(Maybe String)
   }
-  deriving (Show, Generic)
+  deriving (Show)
 
-instance FromJSON CompilerOptions
+instance FromJSON CompilerOptions where
+  parseJSON = withObject "CompilerOptions" $ \v ->
+    CompilerOptions
+      -- We couldn't use the Generic deriving for this because of the _ prefix in the field name.
+      <$> v .:? "module"
+      <*> v .:? "target"
+      <*> v .:? "moduleResolution"
+      <*> v .:? "jsx"
+      <*> v .:? "strict"
+      <*> v .:? "esModuleInterop"
+      <*> v .:? "lib"
+      <*> v .:? "allowJs"
+      <*> v .:? "typeRoots"
+      <*> v .:? "outDir"
 
 analyzeTsConfigContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] TsConfig)
 analyzeTsConfigContent waspDir = runExceptT $ do
   tsConfigFile <- ExceptT findTsConfigOrError
   tsConfig <- ExceptT $ readTsConfigFile tsConfigFile
+  lift $ print tsConfig
   ExceptT $ validateTsConfig tsConfig
   where
     findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
@@ -56,8 +82,77 @@ readTsConfigFile tsConfigFile = do
 
   case parseResult of
     Right tsConfig -> return $ Right tsConfig
-    Left err -> return $ Left [err]
+    Left err -> return $ Left ["Failed to parse tsconfig.json file: " ++ err]
 
--- TODO: validate config fields
 validateTsConfig :: TsConfig -> IO (Either [CompileError] TsConfig)
-validateTsConfig tsConfig = return $ Right tsConfig
+validateTsConfig tsConfig =
+  return $
+    if null tsConfigErrors
+      then Right tsConfig
+      else Left tsConfigErrors
+  where
+    tsConfigErrors =
+      concat
+        [ validateTsConfigField "module" (_module compilerOptionsValues) "esnext",
+          validateTsConfigField "target" (target compilerOptionsValues) "esnext",
+          validateTsConfigField "moduleResolution" (moduleResolution compilerOptionsValues) "bundler",
+          validateTsConfigField "jsx" (jsx compilerOptionsValues) "preserve",
+          validateTsConfigField "strict" (strict compilerOptionsValues) True,
+          validateTsConfigField "esModuleInterop" (esModuleInterop compilerOptionsValues) True,
+          validateTsConfigField "lib" (lib compilerOptionsValues) ["dom", "dom.iterable", "esnext"],
+          validateTsConfigField "allowJs" (allowJs compilerOptionsValues) True,
+          validateTsConfigField "typeRoots" (typeRoots compilerOptionsValues) ["node_modules/@testing-library", "node_modules/@types"],
+          validateTsConfigField "outDir" (outDir compilerOptionsValues) ".wasp/phantom"
+        ]
+    compilerOptionsValues = compilerOptions tsConfig
+
+class ShowJs a where
+  showJs :: a -> String
+
+instance ShowJs String where
+  showJs = show
+
+instance ShowJs [String] where
+  showJs = show
+
+instance ShowJs Bool where
+  showJs True = "true"
+  showJs False = "false"
+
+-- TODO: maybe use a more structured way of defining expected values, so that we can easily add new fields.
+--     expectedValues :: M.Map FieldName TsConfigFieldType
+--     expectedValues =
+--       M.fromList
+--         [ ("module", Str "esnext"),
+--           ("target", Str "esnext"),
+--           ("moduleResolution", Str "bundler"),
+--           ("jsx", Str "preserve"),
+--           ("strict", Bool True),
+--           ("esModuleInterop", Bool True),
+--           ("lib", StrList ["dom", "dom.iterable", "esnext"]),
+--           ("allowJs", Bool True),
+--           ("typeRoots", StrList ["node_modules/@testing-library", "node_modules/@types"]),
+--           ("outDir", Str ".wasp/phantom")
+--         ]
+
+-- data TsConfigFieldType = Str String | Bool Bool | StrList [String]
+
+-- instance Show TsConfigFieldType where
+--   show :: TsConfigFieldType -> String
+--   show (Str s) = s
+--   show (Bool True) = show ("true" :: String)
+--   show (Bool False) = show ("false" :: String)
+--   show (StrList l) = show l
+
+type FieldName = String
+
+validateTsConfigField :: (Eq value, ShowJs value) => FieldName -> Maybe value -> value -> [CompileError]
+validateTsConfigField fieldName Nothing expectedValue = [missingFieldErrorMessage]
+  where
+    missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showJs expectedValue ++ "."]
+validateTsConfigField fieldName (Just userProvidedValue) expectedValue =
+  if userProvidedValue /= expectedValue
+    then [invalidValueErrorMessage]
+    else []
+  where
+    invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected:", showJs expectedValue ++ "."]
diff --git a/waspc/src/Wasp/Generator/SdkGenerator.hs b/waspc/src/Wasp/Generator/SdkGenerator.hs
index c003fa7359..e58ea9c723 100644
--- a/waspc/src/Wasp/Generator/SdkGenerator.hs
+++ b/waspc/src/Wasp/Generator/SdkGenerator.hs
@@ -198,10 +198,11 @@ npmDepsForSdk spec =
           ]
           ++ depsRequiredForAuth spec
           ++ depsRequiredByOAuth spec
-          -- This must be installed in the SDK because it lists prisma/client as a dependency.
+          -- Server auth deps must be installed in the SDK because "@lucia-auth/adapter-prisma"
+          -- lists prisma/client as a dependency.
           -- Installing it inside .wasp/out/server/node_modules would also
           -- install prisma/client in the same folder, which would cause our
-          -- runtime to load the wrong (uninitialized prisma/client)
+          -- runtime to load the wrong (uninitialized prisma/client).
           -- TODO(filip): Find a better way to handle duplicate
           -- dependencies: https://github.com/wasp-lang/wasp/issues/1640
           ++ ServerAuthG.depsRequiredByAuth spec

From c515bd45335a456acfd227a5b296e47d71a6d5c5 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Thu, 19 Sep 2024 14:07:27 +0200
Subject: [PATCH 05/24] Cleanup

---
 waspc/examples/todoApp/tsconfig.json | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/waspc/examples/todoApp/tsconfig.json b/waspc/examples/todoApp/tsconfig.json
index 75adcc205d..4932b229a0 100644
--- a/waspc/examples/todoApp/tsconfig.json
+++ b/waspc/examples/todoApp/tsconfig.json
@@ -15,11 +15,11 @@
     "strict": true,
     // Allow default imports.
     "esModuleInterop": true,
-    // "lib": [
-    //   "dom",
-    //   "dom.iterable",
-    //   "esnext"
-    // ],
+    "lib": [
+      "dom",
+      "dom.iterable",
+      "esnext"
+    ],
     "allowJs": true,
     "typeRoots": [
       // This is needed to properly support Vitest testing with jest-dom matchers.

From 3ebe67abbdb2af6234df47b25adf24dee7cdb2f4 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Thu, 19 Sep 2024 23:45:32 +0200
Subject: [PATCH 06/24] Update tsconfig validation

---
 waspc/src/Wasp/ExternalConfig/TsConfig.hs | 65 +++++++----------------
 1 file changed, 19 insertions(+), 46 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index c289b30b1d..13685a9339 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -1,7 +1,5 @@
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE FlexibleInstances #-}
-{-# LANGUAGE InstanceSigs #-}
-{-# LANGUAGE TypeSynonymInstances #-}
 
 module Wasp.ExternalConfig.TsConfig
   ( TsConfig (..),
@@ -13,7 +11,6 @@ import Control.Monad.Except
 import Data.Aeson (FromJSON, parseJSON, withObject, (.:?))
 import qualified Data.ByteString.Lazy.UTF8 as BS
 import Data.Either.Extra (maybeToEither)
-import qualified Data.Map as M
 import GHC.Generics (Generic)
 import StrongPath (Abs, Dir, File', Path', toFilePath)
 import Wasp.Project.Common
@@ -93,19 +90,20 @@ validateTsConfig tsConfig =
   where
     tsConfigErrors =
       concat
-        [ validateTsConfigField "module" (_module compilerOptionsValues) "esnext",
-          validateTsConfigField "target" (target compilerOptionsValues) "esnext",
-          validateTsConfigField "moduleResolution" (moduleResolution compilerOptionsValues) "bundler",
-          validateTsConfigField "jsx" (jsx compilerOptionsValues) "preserve",
-          validateTsConfigField "strict" (strict compilerOptionsValues) True,
-          validateTsConfigField "esModuleInterop" (esModuleInterop compilerOptionsValues) True,
-          validateTsConfigField "lib" (lib compilerOptionsValues) ["dom", "dom.iterable", "esnext"],
-          validateTsConfigField "allowJs" (allowJs compilerOptionsValues) True,
-          validateTsConfigField "typeRoots" (typeRoots compilerOptionsValues) ["node_modules/@testing-library", "node_modules/@types"],
-          validateTsConfigField "outDir" (outDir compilerOptionsValues) ".wasp/phantom"
+        [ validateRequiredField "module" "esnext" (_module compilerOptionsValues),
+          validateRequiredField "target" "esnext" (target compilerOptionsValues),
+          validateRequiredField "moduleResolution" "bundler" (moduleResolution compilerOptionsValues),
+          validateRequiredField "jsx" "preserve" (jsx compilerOptionsValues),
+          validateRequiredField "strict" True (strict compilerOptionsValues),
+          validateRequiredField "esModuleInterop" True (esModuleInterop compilerOptionsValues),
+          validateRequiredField "lib" ["dom", "dom.iterable", "esnext"] (lib compilerOptionsValues),
+          validateRequiredField "allowJs" True (allowJs compilerOptionsValues),
+          validateRequiredField "typeRoots" ["node_modules/@testing-library", "node_modules/@types"] (typeRoots compilerOptionsValues),
+          validateRequiredField "outDir" ".wasp/phantom" (outDir compilerOptionsValues)
         ]
     compilerOptionsValues = compilerOptions tsConfig
 
+-- | Used to show expected values in error messages.
 class ShowJs a where
   showJs :: a -> String
 
@@ -119,40 +117,15 @@ instance ShowJs Bool where
   showJs True = "true"
   showJs False = "false"
 
--- TODO: maybe use a more structured way of defining expected values, so that we can easily add new fields.
---     expectedValues :: M.Map FieldName TsConfigFieldType
---     expectedValues =
---       M.fromList
---         [ ("module", Str "esnext"),
---           ("target", Str "esnext"),
---           ("moduleResolution", Str "bundler"),
---           ("jsx", Str "preserve"),
---           ("strict", Bool True),
---           ("esModuleInterop", Bool True),
---           ("lib", StrList ["dom", "dom.iterable", "esnext"]),
---           ("allowJs", Bool True),
---           ("typeRoots", StrList ["node_modules/@testing-library", "node_modules/@types"]),
---           ("outDir", Str ".wasp/phantom")
---         ]
-
--- data TsConfigFieldType = Str String | Bool Bool | StrList [String]
-
--- instance Show TsConfigFieldType where
---   show :: TsConfigFieldType -> String
---   show (Str s) = s
---   show (Bool True) = show ("true" :: String)
---   show (Bool False) = show ("false" :: String)
---   show (StrList l) = show l
-
 type FieldName = String
 
-validateTsConfigField :: (Eq value, ShowJs value) => FieldName -> Maybe value -> value -> [CompileError]
-validateTsConfigField fieldName Nothing expectedValue = [missingFieldErrorMessage]
-  where
-    missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showJs expectedValue ++ "."]
-validateTsConfigField fieldName (Just userProvidedValue) expectedValue =
-  if userProvidedValue /= expectedValue
-    then [invalidValueErrorMessage]
-    else []
+validateRequiredField :: (Eq value, ShowJs value) => FieldName -> value -> Maybe value -> [CompileError]
+validateRequiredField fieldName expectedValue maybeUserProvidedValue = case maybeUserProvidedValue of
+  Nothing -> [missingFieldErrorMessage]
+  Just userProvidedValue ->
+    if userProvidedValue /= expectedValue
+      then [invalidValueErrorMessage]
+      else []
   where
     invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected:", showJs expectedValue ++ "."]
+    missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showJs expectedValue ++ "."]

From 78fa56994abb5e9087406e9ed1a618e26a70859e Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Fri, 20 Sep 2024 14:57:06 +0200
Subject: [PATCH 07/24] Cleanup

---
 waspc/src/Wasp/ExternalConfig/TsConfig.hs | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index 13685a9339..19b1abe41a 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -46,7 +46,7 @@ data CompilerOptions = CompilerOptions
 instance FromJSON CompilerOptions where
   parseJSON = withObject "CompilerOptions" $ \v ->
     CompilerOptions
-      -- We couldn't use the Generic deriving for this because of the _ prefix in the field name.
+      -- We couldn't use the Generic deriving for this because of the _ prefix in the "module" field name.
       <$> v .:? "module"
       <*> v .:? "target"
       <*> v .:? "moduleResolution"
@@ -62,7 +62,6 @@ analyzeTsConfigContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileE
 analyzeTsConfigContent waspDir = runExceptT $ do
   tsConfigFile <- ExceptT findTsConfigOrError
   tsConfig <- ExceptT $ readTsConfigFile tsConfigFile
-  lift $ print tsConfig
   ExceptT $ validateTsConfig tsConfig
   where
     findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
@@ -127,5 +126,5 @@ validateRequiredField fieldName expectedValue maybeUserProvidedValue = case mayb
       then [invalidValueErrorMessage]
       else []
   where
-    invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected:", showJs expectedValue ++ "."]
+    invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected value:", showJs expectedValue ++ "."]
     missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showJs expectedValue ++ "."]

From f1245ba5395d4ed3228d468c1a468f9fe35b3d2c Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Fri, 20 Sep 2024 15:13:43 +0200
Subject: [PATCH 08/24] Cleanup

---
 waspc/src/Wasp/ExternalConfig/TsConfig.hs | 32 +++++++++++++----------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index 19b1abe41a..b888d707aa 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -89,18 +89,22 @@ validateTsConfig tsConfig =
   where
     tsConfigErrors =
       concat
-        [ validateRequiredField "module" "esnext" (_module compilerOptionsValues),
-          validateRequiredField "target" "esnext" (target compilerOptionsValues),
-          validateRequiredField "moduleResolution" "bundler" (moduleResolution compilerOptionsValues),
-          validateRequiredField "jsx" "preserve" (jsx compilerOptionsValues),
-          validateRequiredField "strict" True (strict compilerOptionsValues),
-          validateRequiredField "esModuleInterop" True (esModuleInterop compilerOptionsValues),
-          validateRequiredField "lib" ["dom", "dom.iterable", "esnext"] (lib compilerOptionsValues),
-          validateRequiredField "allowJs" True (allowJs compilerOptionsValues),
-          validateRequiredField "typeRoots" ["node_modules/@testing-library", "node_modules/@types"] (typeRoots compilerOptionsValues),
-          validateRequiredField "outDir" ".wasp/phantom" (outDir compilerOptionsValues)
+        [ validateRequiredFieldInCompilerOptions "module" "esnext" _module,
+          validateRequiredFieldInCompilerOptions "target" "esnext" target,
+          validateRequiredFieldInCompilerOptions "moduleResolution" "bundler" moduleResolution,
+          validateRequiredFieldInCompilerOptions "jsx" "preserve" jsx,
+          validateRequiredFieldInCompilerOptions "strict" True strict,
+          validateRequiredFieldInCompilerOptions "esModuleInterop" True esModuleInterop,
+          validateRequiredFieldInCompilerOptions "lib" ["dom", "dom.iterable", "esnext"] lib,
+          validateRequiredFieldInCompilerOptions "allowJs" True allowJs,
+          validateRequiredFieldInCompilerOptions "typeRoots" ["node_modules/@testing-library", "node_modules/@types"] typeRoots,
+          validateRequiredFieldInCompilerOptions "outDir" ".wasp/phantom" outDir
         ]
-    compilerOptionsValues = compilerOptions tsConfig
+
+    validateRequiredFieldInCompilerOptions fieldName expectedValue getField =
+      validateRequiredField fieldName expectedValue $ getField compilerOptionsFields
+
+    compilerOptionsFields = compilerOptions tsConfig
 
 -- | Used to show expected values in error messages.
 class ShowJs a where
@@ -122,9 +126,9 @@ validateRequiredField :: (Eq value, ShowJs value) => FieldName -> value -> Maybe
 validateRequiredField fieldName expectedValue maybeUserProvidedValue = case maybeUserProvidedValue of
   Nothing -> [missingFieldErrorMessage]
   Just userProvidedValue ->
-    if userProvidedValue /= expectedValue
-      then [invalidValueErrorMessage]
-      else []
+    if userProvidedValue == expectedValue
+      then []
+      else [invalidValueErrorMessage]
   where
     invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected value:", showJs expectedValue ++ "."]
     missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showJs expectedValue ++ "."]

From b2594ce176023b44e90b5dd39664e8b0688e642a Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Fri, 20 Sep 2024 17:41:58 +0200
Subject: [PATCH 09/24] Update headless tests. Update field names.

---
 .../examples/todoApp/tsconfig.json            | 23 ++++++++++++-------
 waspc/src/Wasp/ExternalConfig/TsConfig.hs     |  2 +-
 2 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/waspc/headless-test/examples/todoApp/tsconfig.json b/waspc/headless-test/examples/todoApp/tsconfig.json
index a38370e8ee..4932b229a0 100644
--- a/waspc/headless-test/examples/todoApp/tsconfig.json
+++ b/waspc/headless-test/examples/todoApp/tsconfig.json
@@ -5,6 +5,11 @@
 // compiler. Proper TS compiler configuration in Wasp is coming soon :)
 {
   "compilerOptions": {
+    "module": "esnext",
+    "target": "esnext",
+    // We're bundling all code in the end so this is the most appropriate option,
+    // it's also important for autocomplete to work properly.
+    "moduleResolution": "bundler",
     // JSX support
     "jsx": "preserve",
     "strict": true,
@@ -16,19 +21,21 @@
       "esnext"
     ],
     "allowJs": true,
-    "types": [
+    "typeRoots": [
       // This is needed to properly support Vitest testing with jest-dom matchers.
       // Types for jest-dom are not recognized automatically and Typescript complains
       // about missing types e.g. when using `toBeInTheDocument` and other matchers.
-      "@testing-library/jest-dom"
+      "node_modules/@testing-library",
+      // Specifying type roots overrides the default behavior of looking at the
+      // node_modules/@types folder so we had to list it explicitly.
+      // Source 1: https://www.typescriptlang.org/tsconfig#typeRoots 
+      // Source 2: https://github.com/testing-library/jest-dom/issues/546#issuecomment-1889884843
+      "node_modules/@types"
     ],
     // Since this TS config is used only for IDE support and not for
     // compilation, the following directory doesn't exist. We need to specify
     // it to prevent this error:
     // https://stackoverflow.com/questions/42609768/typescript-error-cannot-write-file-because-it-would-overwrite-input-file
-    "outDir": "phantom",
-  },
-  "exclude": [
-    "phantom"
-  ],
-}
\ No newline at end of file
+    "outDir": ".wasp/phantom"
+  }
+}
diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index b888d707aa..1407fa44ad 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -102,7 +102,7 @@ validateTsConfig tsConfig =
         ]
 
     validateRequiredFieldInCompilerOptions fieldName expectedValue getField =
-      validateRequiredField fieldName expectedValue $ getField compilerOptionsFields
+      validateRequiredField ("compilerOptions." ++ fieldName) expectedValue $ getField compilerOptionsFields
 
     compilerOptionsFields = compilerOptions tsConfig
 

From 5db75db9eb138d78f1afe6f7a55299a0e76f1449 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Wed, 25 Sep 2024 18:53:57 +0200
Subject: [PATCH 10/24] Update waspc/src/Wasp/ExternalConfig/TsConfig.hs
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Martin Šošić <Martinsos@users.noreply.github.com>
---
 waspc/src/Wasp/ExternalConfig/TsConfig.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index 1407fa44ad..83874dd02e 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -106,7 +106,7 @@ validateTsConfig tsConfig =
 
     compilerOptionsFields = compilerOptions tsConfig
 
--- | Used to show expected values in error messages.
+-- | Haskell type that implements ShowJS is a type whose values can be mapped to Javascript values (their string representation).
 class ShowJs a where
   showJs :: a -> String
 

From 31cf936e9051995accb40b8613a1958bafd00309 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Wed, 25 Sep 2024 19:02:01 +0200
Subject: [PATCH 11/24] Update comment

---
 waspc/src/Wasp/Util/Json.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/waspc/src/Wasp/Util/Json.hs b/waspc/src/Wasp/Util/Json.hs
index aa43e655c6..fce6b959d9 100644
--- a/waspc/src/Wasp/Util/Json.hs
+++ b/waspc/src/Wasp/Util/Json.hs
@@ -6,6 +6,8 @@ import qualified System.Process as P
 import Wasp.Util.Aeson (decodeFromString)
 
 -- | Uses Node.js to parse JSON with comments by treating it as a JavaScript object.
+-- We used this technique because Aeson can't handle it and we didn't want to write
+-- a custom parser.
 parseJsonWithComments :: FromJSON a => String -> IO (Either String a)
 parseJsonWithComments jsonStr = do
   let evalScript = "const v = " ++ jsonStr ++ ";console.log(JSON.stringify(v));"

From aad26e36345999fb02cf9c02c1cc338635686183 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Wed, 25 Sep 2024 19:12:18 +0200
Subject: [PATCH 12/24] Update package.json validation

---
 waspc/src/Wasp/ExternalConfig/PackageJson.hs | 34 ++++++++------------
 1 file changed, 14 insertions(+), 20 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
index e41771dccd..97ce7452f1 100644
--- a/waspc/src/Wasp/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
@@ -71,12 +71,12 @@ validatePackageJson packageJson =
     packageJsonErrors =
       concat
         [ -- Wasp needs the Wasp SDK to be installed in the project.
-          validate ("wasp", "file:.wasp/out/sdk/wasp", RequiredPackage),
+          validate ("wasp", "file:.wasp/out/sdk/wasp", IsListedWithExactVersion),
           -- Wrong version of Prisma will break the generated code.
-          validate ("prisma", show prismaVersion, RequiredDevPackage),
+          validate ("prisma", show prismaVersion, IsListedAsDevWithExactVersion),
           -- Installing the wrong version of "react-router-dom" can make users believe that they
           -- can use features that are not available in the version that Wasp supports.
-          validate ("react-router-dom", show reactRouterVersion, OptionalPackage)
+          validate ("react-router-dom", show reactRouterVersion, HasExactVersionIfListed)
         ]
     validate = validatePackageInDeps packageJson
 
@@ -88,26 +88,20 @@ readPackageJsonFile packageJsonFile = do
   byteString <- IOUtil.readFileBytes packageJsonFile
   return $ maybeToEither ["Error parsing the package.json file"] $ Aeson.decode byteString
 
-data PackageValidationType = RequiredPackage | RequiredDevPackage | OptionalPackage
+data PackageValidationType = IsListedWithExactVersion | IsListedAsDevWithExactVersion | HasExactVersionIfListed
 
 validatePackageInDeps :: PackageJson -> (PackageName, PackageVersion, PackageValidationType) -> [CompileError]
-validatePackageInDeps packageJson (packageName, expectedPackageVersion, validationType) =
-  case map (M.lookup packageName) depsToCheck of
-    (Just actualPackageVersion : _) ->
-      if actualPackageVersion == expectedPackageVersion
-        then []
-        else [incorrectVersionMessage]
-    _rest -> case validationType of
-      RequiredPackage -> [requiredPackageMessage "dependencies"]
-      RequiredDevPackage -> [requiredPackageMessage "devDependencies"]
-      OptionalPackage -> []
+validatePackageInDeps packageJson (packageName, expectedPackageVersion, validationType) = case validationType of
+  IsListedWithExactVersion -> checkDeps [dependencies packageJson] [requiredPackageMessage "dependencies"]
+  IsListedAsDevWithExactVersion -> checkDeps [devDependencies packageJson] [requiredPackageMessage "devDependencies"]
+  HasExactVersionIfListed -> checkDeps [dependencies packageJson, devDependencies packageJson] []
   where
-    depsToCheck = case validationType of
-      RequiredPackage -> [dependencies packageJson]
-      RequiredDevPackage -> [devDependencies packageJson]
-      -- Users can install packages that don't need to be strictly in dependencies or devDependencies
-      -- which means Wasp needs to check both to validate the correct version of the package.
-      OptionalPackage -> [dependencies packageJson, devDependencies packageJson]
+    checkDeps depsToCheck errorMessagesIfPackageNotListed = case map (M.lookup packageName) depsToCheck of
+      (Just actualPackageVersion : _) ->
+        if actualPackageVersion == expectedPackageVersion
+          then []
+          else [incorrectVersionMessage]
+      _notListed -> errorMessagesIfPackageNotListed
 
     incorrectVersionMessage :: String
     incorrectVersionMessage =

From 6789b0e03aa9785f15e668b4e6dcba76c655a864 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Wed, 25 Sep 2024 19:22:53 +0200
Subject: [PATCH 13/24] Update messages

---
 waspc/src/Wasp/ExternalConfig/PackageJson.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
index 97ce7452f1..478ae4f219 100644
--- a/waspc/src/Wasp/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
@@ -106,16 +106,16 @@ validatePackageInDeps packageJson (packageName, expectedPackageVersion, validati
     incorrectVersionMessage :: String
     incorrectVersionMessage =
       unwords
-        ["The", show packageName, "package must have version", show expectedPackageVersion, "in package.json."]
+        ["Wasp requires package", show packageName, "to be version", show expectedPackageVersion, "in package.json."]
 
     requiredPackageMessage :: String -> String
     requiredPackageMessage packageJsonLocation =
       unwords
-        [ "The",
+        [ "Wasp requires package",
           show packageName,
-          "package with version",
+          "with version",
           show expectedPackageVersion,
-          "must be defined in",
+          "in",
           show packageJsonLocation,
           "in package.json."
         ]

From f16ee595e4dd493a583a09374e9cf32485e46ab8 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Wed, 25 Sep 2024 19:31:30 +0200
Subject: [PATCH 14/24] Update FromJSON instance for TsConfig

---
 waspc/src/Wasp/ExternalConfig/TsConfig.hs | 29 +++++++++++------------
 1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index 83874dd02e..2297a7f5c0 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -8,7 +8,12 @@ module Wasp.ExternalConfig.TsConfig
 where
 
 import Control.Monad.Except
-import Data.Aeson (FromJSON, parseJSON, withObject, (.:?))
+import Data.Aeson
+  ( FromJSON,
+    genericParseJSON,
+    parseJSON,
+  )
+import qualified Data.Aeson as Aeson
 import qualified Data.ByteString.Lazy.UTF8 as BS
 import Data.Either.Extra (maybeToEither)
 import GHC.Generics (Generic)
@@ -41,22 +46,16 @@ data CompilerOptions = CompilerOptions
     typeRoots :: !(Maybe [String]),
     outDir :: !(Maybe String)
   }
-  deriving (Show)
+  deriving (Show, Generic)
 
 instance FromJSON CompilerOptions where
-  parseJSON = withObject "CompilerOptions" $ \v ->
-    CompilerOptions
-      -- We couldn't use the Generic deriving for this because of the _ prefix in the "module" field name.
-      <$> v .:? "module"
-      <*> v .:? "target"
-      <*> v .:? "moduleResolution"
-      <*> v .:? "jsx"
-      <*> v .:? "strict"
-      <*> v .:? "esModuleInterop"
-      <*> v .:? "lib"
-      <*> v .:? "allowJs"
-      <*> v .:? "typeRoots"
-      <*> v .:? "outDir"
+  parseJSON =
+    genericParseJSON $
+      Aeson.defaultOptions {Aeson.fieldLabelModifier = modifyFieldLabel}
+    where
+      -- "module" is a reserved keyword in Haskell, so we use "_module" instead.
+      modifyFieldLabel "_module" = "module"
+      modifyFieldLabel other = other
 
 analyzeTsConfigContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] TsConfig)
 analyzeTsConfigContent waspDir = runExceptT $ do

From 1335462a4297e50a513a842e08a2b45045e9f743 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Wed, 25 Sep 2024 19:39:31 +0200
Subject: [PATCH 15/24] Update TsConfig validation

---
 waspc/src/Wasp/ExternalConfig/TsConfig.hs | 40 +++++++++++------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index 2297a7f5c0..b618a41c31 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -100,34 +100,34 @@ validateTsConfig tsConfig =
           validateRequiredFieldInCompilerOptions "outDir" ".wasp/phantom" outDir
         ]
 
-    validateRequiredFieldInCompilerOptions fieldName expectedValue getField =
-      validateRequiredField ("compilerOptions." ++ fieldName) expectedValue $ getField compilerOptionsFields
+    validateRequiredFieldInCompilerOptions fieldName expectedValue getFieldValue = case getFieldValue compilerOptionsFields of
+      Just actualValue -> validateFieldValue ("compilerOptions." ++ fieldName) expectedValue actualValue
+      Nothing -> [missingFieldErrorMessage]
+      where
+        missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showAsJsValue expectedValue ++ "."]
 
     compilerOptionsFields = compilerOptions tsConfig
 
 -- | Haskell type that implements ShowJS is a type whose values can be mapped to Javascript values (their string representation).
-class ShowJs a where
-  showJs :: a -> String
+class IsJavascriptValue a where
+  showAsJsValue :: a -> String
 
-instance ShowJs String where
-  showJs = show
+instance IsJavascriptValue String where
+  showAsJsValue = show
 
-instance ShowJs [String] where
-  showJs = show
+instance IsJavascriptValue [String] where
+  showAsJsValue = show
 
-instance ShowJs Bool where
-  showJs True = "true"
-  showJs False = "false"
+instance IsJavascriptValue Bool where
+  showAsJsValue True = "true"
+  showAsJsValue False = "false"
 
 type FieldName = String
 
-validateRequiredField :: (Eq value, ShowJs value) => FieldName -> value -> Maybe value -> [CompileError]
-validateRequiredField fieldName expectedValue maybeUserProvidedValue = case maybeUserProvidedValue of
-  Nothing -> [missingFieldErrorMessage]
-  Just userProvidedValue ->
-    if userProvidedValue == expectedValue
-      then []
-      else [invalidValueErrorMessage]
+validateFieldValue :: (Eq value, IsJavascriptValue value) => FieldName -> value -> value -> [CompileError]
+validateFieldValue fieldName expectedValue actualValue =
+  if actualValue == expectedValue
+    then []
+    else [invalidValueErrorMessage]
   where
-    invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected value:", showJs expectedValue ++ "."]
-    missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showJs expectedValue ++ "."]
+    invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected value:", showAsJsValue expectedValue ++ "."]

From 016443edbed1ef93a8e4c233a0c990af56c82a6f Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Thu, 26 Sep 2024 13:23:17 +0200
Subject: [PATCH 16/24] Moves modules into Project and Generator

---
 .../StarterTemplates/Templating.hs            |  2 +-
 waspc/src/Wasp/ExternalConfig.hs              | 31 -------
 waspc/src/Wasp/ExternalConfig/PackageJson.hs  | 88 +-----------------
 waspc/src/Wasp/ExternalConfig/TsConfig.hs     | 89 +------------------
 waspc/src/Wasp/Generator/Common.hs            |  4 -
 .../Generator/ExternalConfig/PackageJson.hs   | 63 +++++++++++++
 .../Wasp/Generator/ExternalConfig/TsConfig.hs | 64 +++++++++++++
 waspc/src/Wasp/Generator/SdkGenerator.hs      |  3 +-
 waspc/src/Wasp/Generator/WebAppGenerator.hs   |  7 +-
 .../Wasp/Generator/WebAppGenerator/Common.hs  |  5 ++
 waspc/src/Wasp/Project/Analyze.hs             |  4 +-
 waspc/src/Wasp/Project/Common.hs              | 16 ++--
 waspc/src/Wasp/Project/ExternalConfig.hs      | 83 +++++++++++++++++
 waspc/waspc.cabal                             |  4 +-
 14 files changed, 240 insertions(+), 223 deletions(-)
 delete mode 100644 waspc/src/Wasp/ExternalConfig.hs
 create mode 100644 waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
 create mode 100644 waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
 create mode 100644 waspc/src/Wasp/Project/ExternalConfig.hs

diff --git a/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs b/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs
index 13a6ec5061..f541431f14 100644
--- a/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs
+++ b/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs
@@ -9,9 +9,9 @@ import qualified Data.Text as T
 import StrongPath (Abs, Dir, File, Path')
 import Wasp.Cli.Command.CreateNewProject.Common (defaultWaspVersionBounds)
 import Wasp.Cli.Command.CreateNewProject.ProjectDescription (NewProjectAppName, NewProjectName)
-import Wasp.ExternalConfig.PackageJson (findPackageJsonFile)
 import Wasp.Project.Analyze (findWaspFile)
 import Wasp.Project.Common (WaspProjectDir)
+import Wasp.Project.ExternalConfig (findPackageJsonFile)
 import qualified Wasp.Util.IO as IOUtil
 
 replaceTemplatePlaceholdersInTemplateFiles :: NewProjectAppName -> NewProjectName -> Path' Abs (Dir WaspProjectDir) -> IO ()
diff --git a/waspc/src/Wasp/ExternalConfig.hs b/waspc/src/Wasp/ExternalConfig.hs
deleted file mode 100644
index b426b5cbd1..0000000000
--- a/waspc/src/Wasp/ExternalConfig.hs
+++ /dev/null
@@ -1,31 +0,0 @@
-module Wasp.ExternalConfig
-  ( ExternalConfigs (..),
-    analyzeExternalConfigs,
-  )
-where
-
-import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
-import StrongPath (Abs, Dir, Path')
-import Wasp.ExternalConfig.PackageJson (PackageJson, analyzePackageJsonContent)
-import Wasp.ExternalConfig.TsConfig (TsConfig, analyzeTsConfigContent)
-import Wasp.Project.Common
-  ( CompileError,
-    WaspProjectDir,
-  )
-
-data ExternalConfigs = ExternalConfigs
-  { packageJson :: PackageJson,
-    tsConfig :: TsConfig
-  }
-  deriving (Show)
-
-analyzeExternalConfigs :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] ExternalConfigs)
-analyzeExternalConfigs waspDir = runExceptT $ do
-  packageJsonContent <- ExceptT $ analyzePackageJsonContent waspDir
-  tsConfigContent <- ExceptT $ analyzeTsConfigContent waspDir
-
-  return $
-    ExternalConfigs
-      { packageJson = packageJsonContent,
-        tsConfig = tsConfigContent
-      }
diff --git a/waspc/src/Wasp/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
index 478ae4f219..8e1f1fd033 100644
--- a/waspc/src/Wasp/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
@@ -2,34 +2,20 @@
 
 module Wasp.ExternalConfig.PackageJson
   ( PackageJson (..),
+    DependenciesMap,
+    PackageName,
+    PackageVersion,
     getDependencies,
     getDevDependencies,
-    analyzePackageJsonContent,
-    findPackageJsonFile,
   )
 where
 
-import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
 import Data.Aeson (FromJSON)
-import qualified Data.Aeson as Aeson
 import Data.Map (Map)
 import qualified Data.Map as M
 import GHC.Generics (Generic)
-import StrongPath (Abs, Dir, File', Path', toFilePath)
 import Wasp.AppSpec.App.Dependency (Dependency)
 import qualified Wasp.AppSpec.App.Dependency as D
-import Wasp.Generator.Common
-  ( prismaVersion,
-    reactRouterVersion,
-  )
-import Wasp.Project.Common
-  ( CompileError,
-    WaspProjectDir,
-    findFileInWaspProjectDir,
-    packageJsonInWaspProjectDir,
-  )
-import Wasp.Util (maybeToEither)
-import qualified Wasp.Util.IO as IOUtil
 
 data PackageJson = PackageJson
   { name :: !String,
@@ -51,71 +37,3 @@ type PackageName = String
 type PackageVersion = String
 
 instance FromJSON PackageJson
-
-analyzePackageJsonContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] PackageJson)
-analyzePackageJsonContent waspProjectDir = runExceptT $ do
-  packageJsonFile <- ExceptT findPackageJsonFileOrError
-  packageJson <- ExceptT $ readPackageJsonFile packageJsonFile
-  ExceptT $ validatePackageJson packageJson
-  where
-    findPackageJsonFileOrError = maybeToEither [fileNotFoundMessage] <$> findPackageJsonFile waspProjectDir
-    fileNotFoundMessage = "Couldn't find the package.json file in the " ++ toFilePath waspProjectDir ++ " directory"
-
-validatePackageJson :: PackageJson -> IO (Either [CompileError] PackageJson)
-validatePackageJson packageJson =
-  return $
-    if null packageJsonErrors
-      then Right packageJson
-      else Left packageJsonErrors
-  where
-    packageJsonErrors =
-      concat
-        [ -- Wasp needs the Wasp SDK to be installed in the project.
-          validate ("wasp", "file:.wasp/out/sdk/wasp", IsListedWithExactVersion),
-          -- Wrong version of Prisma will break the generated code.
-          validate ("prisma", show prismaVersion, IsListedAsDevWithExactVersion),
-          -- Installing the wrong version of "react-router-dom" can make users believe that they
-          -- can use features that are not available in the version that Wasp supports.
-          validate ("react-router-dom", show reactRouterVersion, HasExactVersionIfListed)
-        ]
-    validate = validatePackageInDeps packageJson
-
-findPackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs File'))
-findPackageJsonFile waspProjectDir = findFileInWaspProjectDir waspProjectDir packageJsonInWaspProjectDir
-
-readPackageJsonFile :: Path' Abs File' -> IO (Either [CompileError] PackageJson)
-readPackageJsonFile packageJsonFile = do
-  byteString <- IOUtil.readFileBytes packageJsonFile
-  return $ maybeToEither ["Error parsing the package.json file"] $ Aeson.decode byteString
-
-data PackageValidationType = IsListedWithExactVersion | IsListedAsDevWithExactVersion | HasExactVersionIfListed
-
-validatePackageInDeps :: PackageJson -> (PackageName, PackageVersion, PackageValidationType) -> [CompileError]
-validatePackageInDeps packageJson (packageName, expectedPackageVersion, validationType) = case validationType of
-  IsListedWithExactVersion -> checkDeps [dependencies packageJson] [requiredPackageMessage "dependencies"]
-  IsListedAsDevWithExactVersion -> checkDeps [devDependencies packageJson] [requiredPackageMessage "devDependencies"]
-  HasExactVersionIfListed -> checkDeps [dependencies packageJson, devDependencies packageJson] []
-  where
-    checkDeps depsToCheck errorMessagesIfPackageNotListed = case map (M.lookup packageName) depsToCheck of
-      (Just actualPackageVersion : _) ->
-        if actualPackageVersion == expectedPackageVersion
-          then []
-          else [incorrectVersionMessage]
-      _notListed -> errorMessagesIfPackageNotListed
-
-    incorrectVersionMessage :: String
-    incorrectVersionMessage =
-      unwords
-        ["Wasp requires package", show packageName, "to be version", show expectedPackageVersion, "in package.json."]
-
-    requiredPackageMessage :: String -> String
-    requiredPackageMessage packageJsonLocation =
-      unwords
-        [ "Wasp requires package",
-          show packageName,
-          "with version",
-          show expectedPackageVersion,
-          "in",
-          show packageJsonLocation,
-          "in package.json."
-        ]
diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index b618a41c31..d4d10176f5 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -3,29 +3,17 @@
 
 module Wasp.ExternalConfig.TsConfig
   ( TsConfig (..),
-    analyzeTsConfigContent,
+    CompilerOptions (..),
   )
 where
 
-import Control.Monad.Except
 import Data.Aeson
   ( FromJSON,
     genericParseJSON,
     parseJSON,
   )
 import qualified Data.Aeson as Aeson
-import qualified Data.ByteString.Lazy.UTF8 as BS
-import Data.Either.Extra (maybeToEither)
 import GHC.Generics (Generic)
-import StrongPath (Abs, Dir, File', Path', toFilePath)
-import Wasp.Project.Common
-  ( CompileError,
-    WaspProjectDir,
-    findFileInWaspProjectDir,
-    tsConfigInWaspProjectDir,
-  )
-import qualified Wasp.Util.IO as IOUtil
-import Wasp.Util.Json (parseJsonWithComments)
 
 data TsConfig = TsConfig
   { compilerOptions :: !CompilerOptions
@@ -56,78 +44,3 @@ instance FromJSON CompilerOptions where
       -- "module" is a reserved keyword in Haskell, so we use "_module" instead.
       modifyFieldLabel "_module" = "module"
       modifyFieldLabel other = other
-
-analyzeTsConfigContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] TsConfig)
-analyzeTsConfigContent waspDir = runExceptT $ do
-  tsConfigFile <- ExceptT findTsConfigOrError
-  tsConfig <- ExceptT $ readTsConfigFile tsConfigFile
-  ExceptT $ validateTsConfig tsConfig
-  where
-    findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
-    fileNotFoundMessage = "Couldn't find the tsconfig.json file in the " ++ toFilePath waspDir ++ " directory"
-
-findTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs File'))
-findTsConfigFile waspProjectDir = findFileInWaspProjectDir waspProjectDir tsConfigInWaspProjectDir
-
-readTsConfigFile :: Path' Abs File' -> IO (Either [CompileError] TsConfig)
-readTsConfigFile tsConfigFile = do
-  tsConfigContent <- IOUtil.readFileBytes tsConfigFile
-
-  parseResult <- parseJsonWithComments . BS.toString $ tsConfigContent
-
-  case parseResult of
-    Right tsConfig -> return $ Right tsConfig
-    Left err -> return $ Left ["Failed to parse tsconfig.json file: " ++ err]
-
-validateTsConfig :: TsConfig -> IO (Either [CompileError] TsConfig)
-validateTsConfig tsConfig =
-  return $
-    if null tsConfigErrors
-      then Right tsConfig
-      else Left tsConfigErrors
-  where
-    tsConfigErrors =
-      concat
-        [ validateRequiredFieldInCompilerOptions "module" "esnext" _module,
-          validateRequiredFieldInCompilerOptions "target" "esnext" target,
-          validateRequiredFieldInCompilerOptions "moduleResolution" "bundler" moduleResolution,
-          validateRequiredFieldInCompilerOptions "jsx" "preserve" jsx,
-          validateRequiredFieldInCompilerOptions "strict" True strict,
-          validateRequiredFieldInCompilerOptions "esModuleInterop" True esModuleInterop,
-          validateRequiredFieldInCompilerOptions "lib" ["dom", "dom.iterable", "esnext"] lib,
-          validateRequiredFieldInCompilerOptions "allowJs" True allowJs,
-          validateRequiredFieldInCompilerOptions "typeRoots" ["node_modules/@testing-library", "node_modules/@types"] typeRoots,
-          validateRequiredFieldInCompilerOptions "outDir" ".wasp/phantom" outDir
-        ]
-
-    validateRequiredFieldInCompilerOptions fieldName expectedValue getFieldValue = case getFieldValue compilerOptionsFields of
-      Just actualValue -> validateFieldValue ("compilerOptions." ++ fieldName) expectedValue actualValue
-      Nothing -> [missingFieldErrorMessage]
-      where
-        missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showAsJsValue expectedValue ++ "."]
-
-    compilerOptionsFields = compilerOptions tsConfig
-
--- | Haskell type that implements ShowJS is a type whose values can be mapped to Javascript values (their string representation).
-class IsJavascriptValue a where
-  showAsJsValue :: a -> String
-
-instance IsJavascriptValue String where
-  showAsJsValue = show
-
-instance IsJavascriptValue [String] where
-  showAsJsValue = show
-
-instance IsJavascriptValue Bool where
-  showAsJsValue True = "true"
-  showAsJsValue False = "false"
-
-type FieldName = String
-
-validateFieldValue :: (Eq value, IsJavascriptValue value) => FieldName -> value -> value -> [CompileError]
-validateFieldValue fieldName expectedValue actualValue =
-  if actualValue == expectedValue
-    then []
-    else [invalidValueErrorMessage]
-  where
-    invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected value:", showAsJsValue expectedValue ++ "."]
diff --git a/waspc/src/Wasp/Generator/Common.hs b/waspc/src/Wasp/Generator/Common.hs
index 290abcd386..77523b8348 100644
--- a/waspc/src/Wasp/Generator/Common.hs
+++ b/waspc/src/Wasp/Generator/Common.hs
@@ -11,7 +11,6 @@ module Wasp.Generator.Common
     GeneratedSrcDir,
     makeJsArrayFromHaskellList,
     dropExtensionFromImportPath,
-    reactRouterVersion,
   )
 where
 
@@ -58,9 +57,6 @@ prismaVersion :: SV.Version
 --       Then, make sure `data/Generator/templates/sdk/wasp/prisma-runtime-library.d.ts` is up to date.
 prismaVersion = SV.Version 5 19 1
 
-reactRouterVersion :: SV.ComparatorSet
-reactRouterVersion = SV.backwardsCompatibleWith $ SV.Version 5 3 3
-
 makeJsonWithEntityData :: String -> Aeson.Value
 makeJsonWithEntityData name =
   object
diff --git a/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
new file mode 100644
index 0000000000..613bab6c38
--- /dev/null
+++ b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
@@ -0,0 +1,63 @@
+module Wasp.Generator.ExternalConfig.PackageJson
+  ( validatePackageJson,
+  )
+where
+
+import qualified Data.Map as M
+import qualified Wasp.ExternalConfig.PackageJson as P
+import Wasp.Generator.Common (prismaVersion)
+import Wasp.Generator.WebAppGenerator.Common (reactRouterVersion)
+import Wasp.Project.Common
+  ( CompileError,
+  )
+
+validatePackageJson :: P.PackageJson -> IO (Either [CompileError] P.PackageJson)
+validatePackageJson packageJson =
+  return $
+    if null packageJsonErrors
+      then Right packageJson
+      else Left packageJsonErrors
+  where
+    packageJsonErrors =
+      concat
+        [ -- Wasp needs the Wasp SDK to be installed in the project.
+          validate ("wasp", "file:.wasp/out/sdk/wasp", IsListedWithExactVersion),
+          -- Wrong version of Prisma will break the generated code.
+          validate ("prisma", show prismaVersion, IsListedAsDevWithExactVersion),
+          -- Installing the wrong version of "react-router-dom" can make users believe that they
+          -- can use features that are not available in the version that Wasp supports.
+          validate ("react-router-dom", show reactRouterVersion, HasExactVersionIfListed)
+        ]
+    validate = validatePackageInDeps packageJson
+
+data PackageValidationType = IsListedWithExactVersion | IsListedAsDevWithExactVersion | HasExactVersionIfListed
+
+validatePackageInDeps :: P.PackageJson -> (P.PackageName, P.PackageVersion, PackageValidationType) -> [CompileError]
+validatePackageInDeps packageJson (packageName, expectedPackageVersion, validationType) = case validationType of
+  IsListedWithExactVersion -> checkDeps [P.dependencies packageJson] [requiredPackageMessage "dependencies"]
+  IsListedAsDevWithExactVersion -> checkDeps [P.devDependencies packageJson] [requiredPackageMessage "devDependencies"]
+  HasExactVersionIfListed -> checkDeps [P.dependencies packageJson, P.devDependencies packageJson] []
+  where
+    checkDeps depsToCheck errorMessagesIfPackageNotListed = case map (M.lookup packageName) depsToCheck of
+      (Just actualPackageVersion : _) ->
+        if actualPackageVersion == expectedPackageVersion
+          then []
+          else [incorrectVersionMessage]
+      _notListed -> errorMessagesIfPackageNotListed
+
+    incorrectVersionMessage :: String
+    incorrectVersionMessage =
+      unwords
+        ["Wasp requires package", show packageName, "to be version", show expectedPackageVersion, "in package.json."]
+
+    requiredPackageMessage :: String -> String
+    requiredPackageMessage packageJsonLocation =
+      unwords
+        [ "Wasp requires package",
+          show packageName,
+          "with version",
+          show expectedPackageVersion,
+          "in",
+          show packageJsonLocation,
+          "in package.json."
+        ]
diff --git a/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
new file mode 100644
index 0000000000..9dfb8d4655
--- /dev/null
+++ b/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
@@ -0,0 +1,64 @@
+{-# LANGUAGE FlexibleInstances #-}
+
+module Wasp.Generator.ExternalConfig.TsConfig
+  ( validateTsConfig,
+  )
+where
+
+import qualified Wasp.ExternalConfig.TsConfig as T
+import Wasp.Project.Common
+  ( CompileError,
+  )
+
+validateTsConfig :: T.TsConfig -> IO (Either [CompileError] T.TsConfig)
+validateTsConfig tsConfig =
+  return $
+    if null tsConfigErrors
+      then Right tsConfig
+      else Left tsConfigErrors
+  where
+    tsConfigErrors =
+      concat
+        [ validateRequiredFieldInCompilerOptions "module" "esnext" T._module,
+          validateRequiredFieldInCompilerOptions "target" "esnext" T.target,
+          validateRequiredFieldInCompilerOptions "moduleResolution" "bundler" T.moduleResolution,
+          validateRequiredFieldInCompilerOptions "jsx" "preserve" T.jsx,
+          validateRequiredFieldInCompilerOptions "strict" True T.strict,
+          validateRequiredFieldInCompilerOptions "esModuleInterop" True T.esModuleInterop,
+          validateRequiredFieldInCompilerOptions "lib" ["dom", "dom.iterable", "esnext"] T.lib,
+          validateRequiredFieldInCompilerOptions "allowJs" True T.allowJs,
+          validateRequiredFieldInCompilerOptions "typeRoots" ["node_modules/@testing-library", "node_modules/@types"] T.typeRoots,
+          validateRequiredFieldInCompilerOptions "outDir" ".wasp/phantom" T.outDir
+        ]
+
+    validateRequiredFieldInCompilerOptions fieldName expectedValue getFieldValue = case getFieldValue compilerOptionsFields of
+      Just actualValue -> validateFieldValue ("compilerOptions." ++ fieldName) expectedValue actualValue
+      Nothing -> [missingFieldErrorMessage]
+      where
+        missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showAsJsValue expectedValue ++ "."]
+
+    compilerOptionsFields = T.compilerOptions tsConfig
+
+-- | Haskell type that implements ShowJS is a type whose values can be mapped to Javascript values (their string representation).
+class IsJavascriptValue a where
+  showAsJsValue :: a -> String
+
+instance IsJavascriptValue String where
+  showAsJsValue = show
+
+instance IsJavascriptValue [String] where
+  showAsJsValue = show
+
+instance IsJavascriptValue Bool where
+  showAsJsValue True = "true"
+  showAsJsValue False = "false"
+
+type FieldName = String
+
+validateFieldValue :: (Eq value, IsJavascriptValue value) => FieldName -> value -> value -> [CompileError]
+validateFieldValue fieldName expectedValue actualValue =
+  if actualValue == expectedValue
+    then []
+    else [invalidValueErrorMessage]
+  where
+    invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected value:", showAsJsValue expectedValue ++ "."]
diff --git a/waspc/src/Wasp/Generator/SdkGenerator.hs b/waspc/src/Wasp/Generator/SdkGenerator.hs
index e58ea9c723..35c01a7ed4 100644
--- a/waspc/src/Wasp/Generator/SdkGenerator.hs
+++ b/waspc/src/Wasp/Generator/SdkGenerator.hs
@@ -26,7 +26,7 @@ import qualified Wasp.AppSpec.App.Dependency as AS.Dependency
 import qualified Wasp.AppSpec.ExternalFiles as EC
 import Wasp.AppSpec.Valid (getLowestNodeVersionUserAllows, isAuthEnabled)
 import qualified Wasp.AppSpec.Valid as AS.Valid
-import Wasp.Generator.Common (ProjectRootDir, makeJsonWithEntityData, prismaVersion, reactRouterVersion)
+import Wasp.Generator.Common (ProjectRootDir, makeJsonWithEntityData, prismaVersion)
 import qualified Wasp.Generator.ConfigFile as G.CF
 import Wasp.Generator.DbGenerator (getEntitiesForPrismaSchema)
 import qualified Wasp.Generator.DbGenerator.Auth as DbAuth
@@ -54,6 +54,7 @@ import Wasp.Generator.SdkGenerator.ServerApiG (genServerApi)
 import Wasp.Generator.SdkGenerator.WebSocketGenerator (depsRequiredByWebSockets, genWebSockets)
 import qualified Wasp.Generator.ServerGenerator.AuthG as ServerAuthG
 import qualified Wasp.Generator.ServerGenerator.Common as Server
+import Wasp.Generator.WebAppGenerator.Common (reactRouterVersion)
 import qualified Wasp.Generator.WebAppGenerator.Common as WebApp
 import qualified Wasp.Node.Version as NodeVersion
 import Wasp.Project.Common (WaspProjectDir)
diff --git a/waspc/src/Wasp/Generator/WebAppGenerator.hs b/waspc/src/Wasp/Generator/WebAppGenerator.hs
index 9281b50405..7721304d28 100644
--- a/waspc/src/Wasp/Generator/WebAppGenerator.hs
+++ b/waspc/src/Wasp/Generator/WebAppGenerator.hs
@@ -30,17 +30,14 @@ import qualified Wasp.AppSpec.App.Client as AS.App.Client
 import qualified Wasp.AppSpec.App.Dependency as AS.Dependency
 import Wasp.AppSpec.Valid (getApp)
 import Wasp.Env (envVarsToDotEnvContent)
-import Wasp.Generator.Common
-  ( makeJsArrayFromHaskellList,
-    reactRouterVersion,
-  )
+import Wasp.Generator.Common (makeJsArrayFromHaskellList)
 import Wasp.Generator.FileDraft (FileDraft, createTextFileDraft)
 import qualified Wasp.Generator.FileDraft as FD
 import Wasp.Generator.JsImport (jsImportToImportJson)
 import Wasp.Generator.Monad (Generator)
 import qualified Wasp.Generator.NpmDependencies as N
 import Wasp.Generator.WebAppGenerator.AuthG (genAuth)
-import Wasp.Generator.WebAppGenerator.Common (webAppRootDirInProjectRootDir, webAppSrcDirInWebAppRootDir)
+import Wasp.Generator.WebAppGenerator.Common (reactRouterVersion, webAppRootDirInProjectRootDir, webAppSrcDirInWebAppRootDir)
 import qualified Wasp.Generator.WebAppGenerator.Common as C
 import Wasp.Generator.WebAppGenerator.JsImport (extImportToImportJson)
 import Wasp.Generator.WebAppGenerator.RouterGenerator (genRouter)
diff --git a/waspc/src/Wasp/Generator/WebAppGenerator/Common.hs b/waspc/src/Wasp/Generator/WebAppGenerator/Common.hs
index 3e3c6d623b..ff58b06678 100644
--- a/waspc/src/Wasp/Generator/WebAppGenerator/Common.hs
+++ b/waspc/src/Wasp/Generator/WebAppGenerator/Common.hs
@@ -24,6 +24,7 @@ module Wasp.Generator.WebAppGenerator.Common
     getBaseDir,
     getDefaultDevClientUrl,
     defaultClientPort,
+    reactRouterVersion,
   )
 where
 
@@ -48,6 +49,7 @@ import Wasp.Generator.Common
   )
 import Wasp.Generator.FileDraft (FileDraft, createCopyFileDraft, createTemplateFileDraft)
 import Wasp.Generator.Templates (TemplatesDir)
+import qualified Wasp.SemanticVersion as SV
 
 data WebAppSrcDir
 
@@ -150,3 +152,6 @@ defaultClientPort = 3000
 
 getDefaultDevClientUrl :: AppSpec -> String
 getDefaultDevClientUrl spec = "http://localhost:" ++ show defaultClientPort ++ SP.fromAbsDirP (getBaseDir spec)
+
+reactRouterVersion :: SV.ComparatorSet
+reactRouterVersion = SV.backwardsCompatibleWith $ SV.Version 5 3 3
diff --git a/waspc/src/Wasp/Project/Analyze.hs b/waspc/src/Wasp/Project/Analyze.hs
index e7e5ece230..5cd19cd96a 100644
--- a/waspc/src/Wasp/Project/Analyze.hs
+++ b/waspc/src/Wasp/Project/Analyze.hs
@@ -18,7 +18,6 @@ import Wasp.CompileOptions (CompileOptions)
 import qualified Wasp.CompileOptions as CompileOptions
 import qualified Wasp.ConfigFile as CF
 import Wasp.Error (showCompilerErrorForTerminal)
-import qualified Wasp.ExternalConfig as EC
 import qualified Wasp.Generator.ConfigFile as G.CF
 import Wasp.Project.Common
   ( CompileError,
@@ -31,6 +30,7 @@ import Wasp.Project.Db (makeDevDatabaseUrl)
 import Wasp.Project.Db.Migrations (findMigrationsDir)
 import Wasp.Project.Deployment (loadUserDockerfileContents)
 import Wasp.Project.Env (readDotEnvClient, readDotEnvServer)
+import qualified Wasp.Project.ExternalConfig as EC
 import qualified Wasp.Project.ExternalFiles as ExternalFiles
 import Wasp.Project.Vite (findCustomViteConfigPath)
 import qualified Wasp.Psl.Ast.Schema as Psl.Schema
@@ -94,7 +94,7 @@ constructAppSpec waspDir options externalConfigs parsedPrismaSchema decls = do
   serverEnvVars <- readDotEnvServer waspDir
   clientEnvVars <- readDotEnvClient waspDir
 
-  let packageJsonContent = EC.packageJson externalConfigs
+  let packageJsonContent = EC._packageJson externalConfigs
 
   let appSpec =
         AS.AppSpec
diff --git a/waspc/src/Wasp/Project/Common.hs b/waspc/src/Wasp/Project/Common.hs
index 993c969634..f6541cd725 100644
--- a/waspc/src/Wasp/Project/Common.hs
+++ b/waspc/src/Wasp/Project/Common.hs
@@ -4,6 +4,8 @@ module Wasp.Project.Common
     NodeModulesDir,
     CompileError,
     CompileWarning,
+    PackageJsonFile,
+    TsConfigFile,
     findFileInWaspProjectDir,
     dotWaspDirInWaspProjectDir,
     generatedCodeDirInDotWaspDir,
@@ -22,7 +24,7 @@ module Wasp.Project.Common
   )
 where
 
-import StrongPath (Abs, Dir, File', Path', Rel, reldir, relfile, toFilePath, (</>))
+import StrongPath (Abs, Dir, File, File', Path', Rel, reldir, relfile, toFilePath, (</>))
 import System.Directory (doesFileExist)
 import Wasp.AppSpec.ExternalFiles (SourceExternalCodeDir, SourceExternalPublicDir)
 import qualified Wasp.Generator.Common
@@ -37,6 +39,10 @@ data NodeModulesDir
 
 data DotWaspDir -- Here we put everything that wasp generates.
 
+data PackageJsonFile
+
+data TsConfigFile
+
 -- | NOTE: If you change the depth of this path, also update @waspProjectDirFromProjectRootDir@ below.
 -- TODO: SHould this be renamed to include word "root"?
 dotWaspDirInWaspProjectDir :: Path' (Rel WaspProjectDir) (Dir DotWaspDir)
@@ -67,10 +73,10 @@ dotWaspRootFileInWaspProjectDir = [relfile|.wasproot|]
 dotWaspInfoFileInGeneratedCodeDir :: Path' (Rel Wasp.Generator.Common.ProjectRootDir) File'
 dotWaspInfoFileInGeneratedCodeDir = [relfile|.waspinfo|]
 
-packageJsonInWaspProjectDir :: Path' (Rel WaspProjectDir) File'
+packageJsonInWaspProjectDir :: Path' (Rel WaspProjectDir) (File PackageJsonFile)
 packageJsonInWaspProjectDir = [relfile|package.json|]
 
-tsConfigInWaspProjectDir :: Path' (Rel WaspProjectDir) File'
+tsConfigInWaspProjectDir :: Path' (Rel WaspProjectDir) (File TsConfigFile)
 tsConfigInWaspProjectDir = [relfile|tsconfig.json|]
 
 packageLockJsonInWaspProjectDir :: Path' (Rel WaspProjectDir) File'
@@ -90,8 +96,8 @@ tsconfigInWaspProjectDir = [relfile|tsconfig.json|]
 
 findFileInWaspProjectDir ::
   Path' Abs (Dir WaspProjectDir) ->
-  Path' (Rel WaspProjectDir) File' ->
-  IO (Maybe (Path' Abs File'))
+  Path' (Rel WaspProjectDir) (File file) ->
+  IO (Maybe (Path' Abs (File file)))
 findFileInWaspProjectDir waspDir file = do
   let fileAbsFp = waspDir </> file
   fileExists <- doesFileExist $ toFilePath fileAbsFp
diff --git a/waspc/src/Wasp/Project/ExternalConfig.hs b/waspc/src/Wasp/Project/ExternalConfig.hs
new file mode 100644
index 0000000000..1329f717e0
--- /dev/null
+++ b/waspc/src/Wasp/Project/ExternalConfig.hs
@@ -0,0 +1,83 @@
+module Wasp.Project.ExternalConfig
+  ( analyzeExternalConfigs,
+    findPackageJsonFile,
+    ExternalConfigs (..),
+  )
+where
+
+import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
+import qualified Data.Aeson as Aeson
+import qualified Data.ByteString.Lazy.UTF8 as BS
+import Data.Either.Extra (maybeToEither)
+import StrongPath (Abs, Dir, File, Path', toFilePath)
+import qualified Wasp.ExternalConfig.PackageJson as P
+import qualified Wasp.ExternalConfig.TsConfig as T
+import Wasp.Generator.ExternalConfig.PackageJson (validatePackageJson)
+import Wasp.Generator.ExternalConfig.TsConfig (validateTsConfig)
+import Wasp.Project.Common
+  ( CompileError,
+    PackageJsonFile,
+    TsConfigFile,
+    WaspProjectDir,
+    findFileInWaspProjectDir,
+    packageJsonInWaspProjectDir,
+    tsConfigInWaspProjectDir,
+  )
+import qualified Wasp.Util.IO as IOUtil
+import Wasp.Util.Json (parseJsonWithComments)
+
+data ExternalConfigs = ExternalConfigs
+  { _packageJson :: P.PackageJson,
+    _tsConfig :: T.TsConfig
+  }
+  deriving (Show)
+
+analyzeExternalConfigs :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] ExternalConfigs)
+analyzeExternalConfigs waspDir = runExceptT $ do
+  packageJsonContent <- ExceptT $ analyzePackageJsonContent waspDir
+  tsConfigContent <- ExceptT $ analyzeTsConfigContent waspDir
+
+  return $
+    ExternalConfigs
+      { _packageJson = packageJsonContent,
+        _tsConfig = tsConfigContent
+      }
+
+analyzePackageJsonContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] P.PackageJson)
+analyzePackageJsonContent waspProjectDir = runExceptT $ do
+  packageJsonFile <- ExceptT findPackageJsonFileOrError
+  packageJson <- ExceptT $ readPackageJsonFile packageJsonFile
+  ExceptT $ validatePackageJson packageJson
+  where
+    findPackageJsonFileOrError = maybeToEither [fileNotFoundMessage] <$> findPackageJsonFile waspProjectDir
+    fileNotFoundMessage = "Couldn't find the package.json file in the " ++ toFilePath waspProjectDir ++ " directory"
+
+findPackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs (File PackageJsonFile)))
+findPackageJsonFile waspProjectDir = findFileInWaspProjectDir waspProjectDir packageJsonInWaspProjectDir
+
+readPackageJsonFile :: Path' Abs (File PackageJsonFile) -> IO (Either [CompileError] P.PackageJson)
+readPackageJsonFile packageJsonFile = do
+  byteString <- IOUtil.readFileBytes packageJsonFile
+  return $ maybeToEither ["Error parsing the package.json file"] $ Aeson.decode byteString
+
+analyzeTsConfigContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] T.TsConfig)
+analyzeTsConfigContent waspDir = runExceptT $ do
+  tsConfigFile <- ExceptT findTsConfigOrError
+  tsConfig <- ExceptT $ readTsConfigFile tsConfigFile
+  ExceptT $ validateTsConfig tsConfig
+  where
+    findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
+    fileNotFoundMessage = "Couldn't find the tsconfig.json file in the " ++ toFilePath waspDir ++ " directory"
+
+findTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs (File TsConfigFile)))
+findTsConfigFile waspProjectDir = findFileInWaspProjectDir waspProjectDir tsConfigInWaspProjectDir
+
+readTsConfigFile :: Path' Abs (File TsConfigFile) -> IO (Either [CompileError] T.TsConfig)
+readTsConfigFile tsConfigFile = do
+  tsConfigContent <- IOUtil.readFileBytes tsConfigFile
+
+  parseResult <- parseJsonWithComments . BS.toString $ tsConfigContent
+
+  case parseResult of
+    Right tsConfig -> return $ Right tsConfig
+    Left err -> return $ Left ["Failed to parse tsconfig.json file: " ++ err]
diff --git a/waspc/waspc.cabal b/waspc/waspc.cabal
index 33b82e7764..d85c42ce36 100644
--- a/waspc/waspc.cabal
+++ b/waspc/waspc.cabal
@@ -259,7 +259,6 @@ library
     Wasp.Db.Postgres
     Wasp.Error
     Wasp.Env
-    Wasp.ExternalConfig
     Wasp.ExternalConfig.PackageJson
     Wasp.ExternalConfig.TsConfig
     Wasp.Generator
@@ -280,6 +279,8 @@ library
     Wasp.Generator.DbGenerator.Operations
     Wasp.Generator.DockerGenerator
     Wasp.Generator.ExternalCodeGenerator.Common
+    Wasp.Generator.ExternalConfig.PackageJson
+    Wasp.Generator.ExternalConfig.TsConfig
     Wasp.Generator.FileDraft
     Wasp.Generator.FileDraft.CopyDirFileDraft
     Wasp.Generator.FileDraft.CopyFileDraft
@@ -366,6 +367,7 @@ library
     Wasp.Project.Db.Dev.Sqlite
     Wasp.Project.Deployment
     Wasp.Project.Env
+    Wasp.Project.ExternalConfig
     Wasp.Project.ExternalFiles
     Wasp.Project.Studio
     Wasp.Project.Vite

From e26238d2dfde0e434abc08c780ff9f873d751fc3 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Thu, 26 Sep 2024 14:14:18 +0200
Subject: [PATCH 17/24] Extract PackageJson and TsConfig in Project modules

---
 .../StarterTemplates/Templating.hs            |  2 +-
 waspc/src/Wasp/Project/ExternalConfig.hs      | 60 ++-----------------
 .../Project/ExternalConfig/PackageJson.hs     | 37 ++++++++++++
 .../Wasp/Project/ExternalConfig/TsConfig.hs   | 42 +++++++++++++
 waspc/waspc.cabal                             |  2 +
 5 files changed, 87 insertions(+), 56 deletions(-)
 create mode 100644 waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs
 create mode 100644 waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs

diff --git a/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs b/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs
index f541431f14..7c3cb58570 100644
--- a/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs
+++ b/waspc/cli/src/Wasp/Cli/Command/CreateNewProject/StarterTemplates/Templating.hs
@@ -11,7 +11,7 @@ import Wasp.Cli.Command.CreateNewProject.Common (defaultWaspVersionBounds)
 import Wasp.Cli.Command.CreateNewProject.ProjectDescription (NewProjectAppName, NewProjectName)
 import Wasp.Project.Analyze (findWaspFile)
 import Wasp.Project.Common (WaspProjectDir)
-import Wasp.Project.ExternalConfig (findPackageJsonFile)
+import Wasp.Project.ExternalConfig.PackageJson (findPackageJsonFile)
 import qualified Wasp.Util.IO as IOUtil
 
 replaceTemplatePlaceholdersInTemplateFiles :: NewProjectAppName -> NewProjectName -> Path' Abs (Dir WaspProjectDir) -> IO ()
diff --git a/waspc/src/Wasp/Project/ExternalConfig.hs b/waspc/src/Wasp/Project/ExternalConfig.hs
index 1329f717e0..c03a2732de 100644
--- a/waspc/src/Wasp/Project/ExternalConfig.hs
+++ b/waspc/src/Wasp/Project/ExternalConfig.hs
@@ -1,30 +1,19 @@
 module Wasp.Project.ExternalConfig
   ( analyzeExternalConfigs,
-    findPackageJsonFile,
     ExternalConfigs (..),
   )
 where
 
 import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
-import qualified Data.Aeson as Aeson
-import qualified Data.ByteString.Lazy.UTF8 as BS
-import Data.Either.Extra (maybeToEither)
-import StrongPath (Abs, Dir, File, Path', toFilePath)
+import StrongPath (Abs, Dir, Path')
 import qualified Wasp.ExternalConfig.PackageJson as P
 import qualified Wasp.ExternalConfig.TsConfig as T
-import Wasp.Generator.ExternalConfig.PackageJson (validatePackageJson)
-import Wasp.Generator.ExternalConfig.TsConfig (validateTsConfig)
 import Wasp.Project.Common
   ( CompileError,
-    PackageJsonFile,
-    TsConfigFile,
     WaspProjectDir,
-    findFileInWaspProjectDir,
-    packageJsonInWaspProjectDir,
-    tsConfigInWaspProjectDir,
   )
-import qualified Wasp.Util.IO as IOUtil
-import Wasp.Util.Json (parseJsonWithComments)
+import Wasp.Project.ExternalConfig.PackageJson (analyzePackageJsonFile)
+import Wasp.Project.ExternalConfig.TsConfig (analyzeTsConfigFile)
 
 data ExternalConfigs = ExternalConfigs
   { _packageJson :: P.PackageJson,
@@ -34,50 +23,11 @@ data ExternalConfigs = ExternalConfigs
 
 analyzeExternalConfigs :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] ExternalConfigs)
 analyzeExternalConfigs waspDir = runExceptT $ do
-  packageJsonContent <- ExceptT $ analyzePackageJsonContent waspDir
-  tsConfigContent <- ExceptT $ analyzeTsConfigContent waspDir
+  packageJsonContent <- ExceptT $ analyzePackageJsonFile waspDir
+  tsConfigContent <- ExceptT $ analyzeTsConfigFile waspDir
 
   return $
     ExternalConfigs
       { _packageJson = packageJsonContent,
         _tsConfig = tsConfigContent
       }
-
-analyzePackageJsonContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] P.PackageJson)
-analyzePackageJsonContent waspProjectDir = runExceptT $ do
-  packageJsonFile <- ExceptT findPackageJsonFileOrError
-  packageJson <- ExceptT $ readPackageJsonFile packageJsonFile
-  ExceptT $ validatePackageJson packageJson
-  where
-    findPackageJsonFileOrError = maybeToEither [fileNotFoundMessage] <$> findPackageJsonFile waspProjectDir
-    fileNotFoundMessage = "Couldn't find the package.json file in the " ++ toFilePath waspProjectDir ++ " directory"
-
-findPackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs (File PackageJsonFile)))
-findPackageJsonFile waspProjectDir = findFileInWaspProjectDir waspProjectDir packageJsonInWaspProjectDir
-
-readPackageJsonFile :: Path' Abs (File PackageJsonFile) -> IO (Either [CompileError] P.PackageJson)
-readPackageJsonFile packageJsonFile = do
-  byteString <- IOUtil.readFileBytes packageJsonFile
-  return $ maybeToEither ["Error parsing the package.json file"] $ Aeson.decode byteString
-
-analyzeTsConfigContent :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] T.TsConfig)
-analyzeTsConfigContent waspDir = runExceptT $ do
-  tsConfigFile <- ExceptT findTsConfigOrError
-  tsConfig <- ExceptT $ readTsConfigFile tsConfigFile
-  ExceptT $ validateTsConfig tsConfig
-  where
-    findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
-    fileNotFoundMessage = "Couldn't find the tsconfig.json file in the " ++ toFilePath waspDir ++ " directory"
-
-findTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs (File TsConfigFile)))
-findTsConfigFile waspProjectDir = findFileInWaspProjectDir waspProjectDir tsConfigInWaspProjectDir
-
-readTsConfigFile :: Path' Abs (File TsConfigFile) -> IO (Either [CompileError] T.TsConfig)
-readTsConfigFile tsConfigFile = do
-  tsConfigContent <- IOUtil.readFileBytes tsConfigFile
-
-  parseResult <- parseJsonWithComments . BS.toString $ tsConfigContent
-
-  case parseResult of
-    Right tsConfig -> return $ Right tsConfig
-    Left err -> return $ Left ["Failed to parse tsconfig.json file: " ++ err]
diff --git a/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs
new file mode 100644
index 0000000000..8aa3509465
--- /dev/null
+++ b/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs
@@ -0,0 +1,37 @@
+module Wasp.Project.ExternalConfig.PackageJson
+  ( analyzePackageJsonFile,
+    findPackageJsonFile,
+  )
+where
+
+import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
+import qualified Data.Aeson as Aeson
+import Data.Either.Extra (maybeToEither)
+import StrongPath (Abs, Dir, File, Path', toFilePath)
+import qualified Wasp.ExternalConfig.PackageJson as P
+import Wasp.Generator.ExternalConfig.PackageJson (validatePackageJson)
+import Wasp.Project.Common
+  ( CompileError,
+    PackageJsonFile,
+    WaspProjectDir,
+    findFileInWaspProjectDir,
+    packageJsonInWaspProjectDir,
+  )
+import qualified Wasp.Util.IO as IOUtil
+
+analyzePackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] P.PackageJson)
+analyzePackageJsonFile waspProjectDir = runExceptT $ do
+  packageJsonFile <- ExceptT findPackageJsonFileOrError
+  packageJson <- ExceptT $ readPackageJsonFile packageJsonFile
+  ExceptT $ validatePackageJson packageJson
+  where
+    findPackageJsonFileOrError = maybeToEither [fileNotFoundMessage] <$> findPackageJsonFile waspProjectDir
+    fileNotFoundMessage = "Couldn't find the package.json file in the " ++ toFilePath waspProjectDir ++ " directory"
+
+findPackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs (File PackageJsonFile)))
+findPackageJsonFile waspProjectDir = findFileInWaspProjectDir waspProjectDir packageJsonInWaspProjectDir
+
+readPackageJsonFile :: Path' Abs (File PackageJsonFile) -> IO (Either [CompileError] P.PackageJson)
+readPackageJsonFile packageJsonFile = do
+  byteString <- IOUtil.readFileBytes packageJsonFile
+  return $ maybeToEither ["Error parsing the package.json file"] $ Aeson.decode byteString
diff --git a/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs
new file mode 100644
index 0000000000..47c85fcc16
--- /dev/null
+++ b/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs
@@ -0,0 +1,42 @@
+module Wasp.Project.ExternalConfig.TsConfig
+  ( analyzeTsConfigFile,
+  )
+where
+
+import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
+import qualified Data.ByteString.Lazy.UTF8 as BS
+import Data.Either.Extra (maybeToEither)
+import StrongPath (Abs, Dir, File, Path', toFilePath)
+import qualified Wasp.ExternalConfig.TsConfig as T
+import Wasp.Generator.ExternalConfig.TsConfig (validateTsConfig)
+import Wasp.Project.Common
+  ( CompileError,
+    TsConfigFile,
+    WaspProjectDir,
+    findFileInWaspProjectDir,
+    tsConfigInWaspProjectDir,
+  )
+import qualified Wasp.Util.IO as IOUtil
+import Wasp.Util.Json (parseJsonWithComments)
+
+analyzeTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] T.TsConfig)
+analyzeTsConfigFile waspDir = runExceptT $ do
+  tsConfigFile <- ExceptT findTsConfigOrError
+  tsConfig <- ExceptT $ readTsConfigFile tsConfigFile
+  ExceptT $ validateTsConfig tsConfig
+  where
+    findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
+    fileNotFoundMessage = "Couldn't find the tsconfig.json file in the " ++ toFilePath waspDir ++ " directory"
+
+findTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs (File TsConfigFile)))
+findTsConfigFile waspProjectDir = findFileInWaspProjectDir waspProjectDir tsConfigInWaspProjectDir
+
+readTsConfigFile :: Path' Abs (File TsConfigFile) -> IO (Either [CompileError] T.TsConfig)
+readTsConfigFile tsConfigFile = do
+  tsConfigContent <- IOUtil.readFileBytes tsConfigFile
+
+  parseResult <- parseJsonWithComments . BS.toString $ tsConfigContent
+
+  case parseResult of
+    Right tsConfig -> return $ Right tsConfig
+    Left err -> return $ Left ["Failed to parse tsconfig.json file: " ++ err]
diff --git a/waspc/waspc.cabal b/waspc/waspc.cabal
index d85c42ce36..b8e1b353d7 100644
--- a/waspc/waspc.cabal
+++ b/waspc/waspc.cabal
@@ -368,6 +368,8 @@ library
     Wasp.Project.Deployment
     Wasp.Project.Env
     Wasp.Project.ExternalConfig
+    Wasp.Project.ExternalConfig.PackageJson
+    Wasp.Project.ExternalConfig.TsConfig
     Wasp.Project.ExternalFiles
     Wasp.Project.Studio
     Wasp.Project.Vite

From dbafdcea5e7a810410b4d59a2ebe16c6e4e64fc8 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Thu, 26 Sep 2024 14:15:40 +0200
Subject: [PATCH 18/24] Update naming

---
 waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
index 613bab6c38..2fdd868fe1 100644
--- a/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
@@ -28,12 +28,12 @@ validatePackageJson packageJson =
           -- can use features that are not available in the version that Wasp supports.
           validate ("react-router-dom", show reactRouterVersion, HasExactVersionIfListed)
         ]
-    validate = validatePackageInDeps packageJson
+    validate = validateDep packageJson
 
 data PackageValidationType = IsListedWithExactVersion | IsListedAsDevWithExactVersion | HasExactVersionIfListed
 
-validatePackageInDeps :: P.PackageJson -> (P.PackageName, P.PackageVersion, PackageValidationType) -> [CompileError]
-validatePackageInDeps packageJson (packageName, expectedPackageVersion, validationType) = case validationType of
+validateDep :: P.PackageJson -> (P.PackageName, P.PackageVersion, PackageValidationType) -> [CompileError]
+validateDep packageJson (packageName, expectedPackageVersion, validationType) = case validationType of
   IsListedWithExactVersion -> checkDeps [P.dependencies packageJson] [requiredPackageMessage "dependencies"]
   IsListedAsDevWithExactVersion -> checkDeps [P.devDependencies packageJson] [requiredPackageMessage "devDependencies"]
   HasExactVersionIfListed -> checkDeps [P.dependencies packageJson, P.devDependencies packageJson] []

From d3fd09f94c679dea0c3047dbb55f107c1bf008f5 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Thu, 26 Sep 2024 14:36:27 +0200
Subject: [PATCH 19/24] Update validation fns

---
 .../Generator/ExternalConfig/PackageJson.hs   | 29 ++++++---------
 .../Wasp/Generator/ExternalConfig/TsConfig.hs | 36 ++++++++-----------
 .../Project/ExternalConfig/PackageJson.hs     | 10 +++---
 .../Wasp/Project/ExternalConfig/TsConfig.hs   | 10 +++---
 waspc/src/Wasp/Util.hs                        |  7 ++++
 5 files changed, 42 insertions(+), 50 deletions(-)

diff --git a/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
index 2fdd868fe1..0473d3b5d0 100644
--- a/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
@@ -7,32 +7,25 @@ import qualified Data.Map as M
 import qualified Wasp.ExternalConfig.PackageJson as P
 import Wasp.Generator.Common (prismaVersion)
 import Wasp.Generator.WebAppGenerator.Common (reactRouterVersion)
-import Wasp.Project.Common
-  ( CompileError,
-  )
 
-validatePackageJson :: P.PackageJson -> IO (Either [CompileError] P.PackageJson)
+validatePackageJson :: P.PackageJson -> IO [String]
 validatePackageJson packageJson =
   return $
-    if null packageJsonErrors
-      then Right packageJson
-      else Left packageJsonErrors
+    concat
+      [ -- Wasp needs the Wasp SDK to be installed in the project.
+        validate ("wasp", "file:.wasp/out/sdk/wasp", IsListedWithExactVersion),
+        -- Wrong version of Prisma will break the generated code.
+        validate ("prisma", show prismaVersion, IsListedAsDevWithExactVersion),
+        -- Installing the wrong version of "react-router-dom" can make users believe that they
+        -- can use features that are not available in the version that Wasp supports.
+        validate ("react-router-dom", show reactRouterVersion, HasExactVersionIfListed)
+      ]
   where
-    packageJsonErrors =
-      concat
-        [ -- Wasp needs the Wasp SDK to be installed in the project.
-          validate ("wasp", "file:.wasp/out/sdk/wasp", IsListedWithExactVersion),
-          -- Wrong version of Prisma will break the generated code.
-          validate ("prisma", show prismaVersion, IsListedAsDevWithExactVersion),
-          -- Installing the wrong version of "react-router-dom" can make users believe that they
-          -- can use features that are not available in the version that Wasp supports.
-          validate ("react-router-dom", show reactRouterVersion, HasExactVersionIfListed)
-        ]
     validate = validateDep packageJson
 
 data PackageValidationType = IsListedWithExactVersion | IsListedAsDevWithExactVersion | HasExactVersionIfListed
 
-validateDep :: P.PackageJson -> (P.PackageName, P.PackageVersion, PackageValidationType) -> [CompileError]
+validateDep :: P.PackageJson -> (P.PackageName, P.PackageVersion, PackageValidationType) -> [String]
 validateDep packageJson (packageName, expectedPackageVersion, validationType) = case validationType of
   IsListedWithExactVersion -> checkDeps [P.dependencies packageJson] [requiredPackageMessage "dependencies"]
   IsListedAsDevWithExactVersion -> checkDeps [P.devDependencies packageJson] [requiredPackageMessage "devDependencies"]
diff --git a/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
index 9dfb8d4655..f3f9a04c13 100644
--- a/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
@@ -6,31 +6,23 @@ module Wasp.Generator.ExternalConfig.TsConfig
 where
 
 import qualified Wasp.ExternalConfig.TsConfig as T
-import Wasp.Project.Common
-  ( CompileError,
-  )
 
-validateTsConfig :: T.TsConfig -> IO (Either [CompileError] T.TsConfig)
+validateTsConfig :: T.TsConfig -> IO [String]
 validateTsConfig tsConfig =
   return $
-    if null tsConfigErrors
-      then Right tsConfig
-      else Left tsConfigErrors
+    concat
+      [ validateRequiredFieldInCompilerOptions "module" "esnext" T._module,
+        validateRequiredFieldInCompilerOptions "target" "esnext" T.target,
+        validateRequiredFieldInCompilerOptions "moduleResolution" "bundler" T.moduleResolution,
+        validateRequiredFieldInCompilerOptions "jsx" "preserve" T.jsx,
+        validateRequiredFieldInCompilerOptions "strict" True T.strict,
+        validateRequiredFieldInCompilerOptions "esModuleInterop" True T.esModuleInterop,
+        validateRequiredFieldInCompilerOptions "lib" ["dom", "dom.iterable", "esnext"] T.lib,
+        validateRequiredFieldInCompilerOptions "allowJs" True T.allowJs,
+        validateRequiredFieldInCompilerOptions "typeRoots" ["node_modules/@testing-library", "node_modules/@types"] T.typeRoots,
+        validateRequiredFieldInCompilerOptions "outDir" ".wasp/phantom" T.outDir
+      ]
   where
-    tsConfigErrors =
-      concat
-        [ validateRequiredFieldInCompilerOptions "module" "esnext" T._module,
-          validateRequiredFieldInCompilerOptions "target" "esnext" T.target,
-          validateRequiredFieldInCompilerOptions "moduleResolution" "bundler" T.moduleResolution,
-          validateRequiredFieldInCompilerOptions "jsx" "preserve" T.jsx,
-          validateRequiredFieldInCompilerOptions "strict" True T.strict,
-          validateRequiredFieldInCompilerOptions "esModuleInterop" True T.esModuleInterop,
-          validateRequiredFieldInCompilerOptions "lib" ["dom", "dom.iterable", "esnext"] T.lib,
-          validateRequiredFieldInCompilerOptions "allowJs" True T.allowJs,
-          validateRequiredFieldInCompilerOptions "typeRoots" ["node_modules/@testing-library", "node_modules/@types"] T.typeRoots,
-          validateRequiredFieldInCompilerOptions "outDir" ".wasp/phantom" T.outDir
-        ]
-
     validateRequiredFieldInCompilerOptions fieldName expectedValue getFieldValue = case getFieldValue compilerOptionsFields of
       Just actualValue -> validateFieldValue ("compilerOptions." ++ fieldName) expectedValue actualValue
       Nothing -> [missingFieldErrorMessage]
@@ -55,7 +47,7 @@ instance IsJavascriptValue Bool where
 
 type FieldName = String
 
-validateFieldValue :: (Eq value, IsJavascriptValue value) => FieldName -> value -> value -> [CompileError]
+validateFieldValue :: (Eq value, IsJavascriptValue value) => FieldName -> value -> value -> [String]
 validateFieldValue fieldName expectedValue actualValue =
   if actualValue == expectedValue
     then []
diff --git a/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs
index 8aa3509465..a46fd9e800 100644
--- a/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs
@@ -11,19 +11,19 @@ import StrongPath (Abs, Dir, File, Path', toFilePath)
 import qualified Wasp.ExternalConfig.PackageJson as P
 import Wasp.Generator.ExternalConfig.PackageJson (validatePackageJson)
 import Wasp.Project.Common
-  ( CompileError,
-    PackageJsonFile,
+  ( PackageJsonFile,
     WaspProjectDir,
     findFileInWaspProjectDir,
     packageJsonInWaspProjectDir,
   )
+import Wasp.Util (validateToEither)
 import qualified Wasp.Util.IO as IOUtil
 
-analyzePackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] P.PackageJson)
+analyzePackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Either [String] P.PackageJson)
 analyzePackageJsonFile waspProjectDir = runExceptT $ do
   packageJsonFile <- ExceptT findPackageJsonFileOrError
   packageJson <- ExceptT $ readPackageJsonFile packageJsonFile
-  ExceptT $ validatePackageJson packageJson
+  ExceptT $ validateToEither validatePackageJson packageJson
   where
     findPackageJsonFileOrError = maybeToEither [fileNotFoundMessage] <$> findPackageJsonFile waspProjectDir
     fileNotFoundMessage = "Couldn't find the package.json file in the " ++ toFilePath waspProjectDir ++ " directory"
@@ -31,7 +31,7 @@ analyzePackageJsonFile waspProjectDir = runExceptT $ do
 findPackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs (File PackageJsonFile)))
 findPackageJsonFile waspProjectDir = findFileInWaspProjectDir waspProjectDir packageJsonInWaspProjectDir
 
-readPackageJsonFile :: Path' Abs (File PackageJsonFile) -> IO (Either [CompileError] P.PackageJson)
+readPackageJsonFile :: Path' Abs (File PackageJsonFile) -> IO (Either [String] P.PackageJson)
 readPackageJsonFile packageJsonFile = do
   byteString <- IOUtil.readFileBytes packageJsonFile
   return $ maybeToEither ["Error parsing the package.json file"] $ Aeson.decode byteString
diff --git a/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs
index 47c85fcc16..2ca9027d31 100644
--- a/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs
@@ -10,20 +10,20 @@ import StrongPath (Abs, Dir, File, Path', toFilePath)
 import qualified Wasp.ExternalConfig.TsConfig as T
 import Wasp.Generator.ExternalConfig.TsConfig (validateTsConfig)
 import Wasp.Project.Common
-  ( CompileError,
-    TsConfigFile,
+  ( TsConfigFile,
     WaspProjectDir,
     findFileInWaspProjectDir,
     tsConfigInWaspProjectDir,
   )
+import Wasp.Util (validateToEither)
 import qualified Wasp.Util.IO as IOUtil
 import Wasp.Util.Json (parseJsonWithComments)
 
-analyzeTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Either [CompileError] T.TsConfig)
+analyzeTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Either [String] T.TsConfig)
 analyzeTsConfigFile waspDir = runExceptT $ do
   tsConfigFile <- ExceptT findTsConfigOrError
   tsConfig <- ExceptT $ readTsConfigFile tsConfigFile
-  ExceptT $ validateTsConfig tsConfig
+  ExceptT $ validateToEither validateTsConfig tsConfig
   where
     findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
     fileNotFoundMessage = "Couldn't find the tsconfig.json file in the " ++ toFilePath waspDir ++ " directory"
@@ -31,7 +31,7 @@ analyzeTsConfigFile waspDir = runExceptT $ do
 findTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Maybe (Path' Abs (File TsConfigFile)))
 findTsConfigFile waspProjectDir = findFileInWaspProjectDir waspProjectDir tsConfigInWaspProjectDir
 
-readTsConfigFile :: Path' Abs (File TsConfigFile) -> IO (Either [CompileError] T.TsConfig)
+readTsConfigFile :: Path' Abs (File TsConfigFile) -> IO (Either [String] T.TsConfig)
 readTsConfigFile tsConfigFile = do
   tsConfigContent <- IOUtil.readFileBytes tsConfigFile
 
diff --git a/waspc/src/Wasp/Util.hs b/waspc/src/Wasp/Util.hs
index 9cedb4e0d7..1907da3ec4 100644
--- a/waspc/src/Wasp/Util.hs
+++ b/waspc/src/Wasp/Util.hs
@@ -40,6 +40,7 @@ module Wasp.Util
     trim,
     secondsToMicroSeconds,
     findDuplicateElems,
+    validateToEither,
   )
 where
 
@@ -270,3 +271,9 @@ secondsToMicroSeconds = (* 1000000)
 
 findDuplicateElems :: Ord a => [a] -> [a]
 findDuplicateElems = map head . filter ((> 1) . length) . group . sort
+
+validateToEither :: (Monad m) => (a -> m [String]) -> a -> m (Either [String] a)
+validateToEither validateFn input =
+  validateFn input >>= \case
+    [] -> return $ Right input
+    errors -> return $ Left errors

From bcb33db3fb34e03a5ca8b72801a44ca7c024849d Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Fri, 27 Sep 2024 12:23:23 +0200
Subject: [PATCH 20/24] Update waspc/src/Wasp/Util/Json.hs
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Martin Šošić <Martinsos@users.noreply.github.com>
---
 waspc/src/Wasp/Util/Json.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/waspc/src/Wasp/Util/Json.hs b/waspc/src/Wasp/Util/Json.hs
index fce6b959d9..dc7128ec1b 100644
--- a/waspc/src/Wasp/Util/Json.hs
+++ b/waspc/src/Wasp/Util/Json.hs
@@ -6,7 +6,7 @@ import qualified System.Process as P
 import Wasp.Util.Aeson (decodeFromString)
 
 -- | Uses Node.js to parse JSON with comments by treating it as a JavaScript object.
--- We used this technique because Aeson can't handle it and we didn't want to write
+-- We use this technique because Aeson can't read JSON with comments and we didn't want to write
 -- a custom parser.
 parseJsonWithComments :: FromJSON a => String -> IO (Either String a)
 parseJsonWithComments jsonStr = do

From 3086ed14afd650c24c251da9b8b61abc7d27add2 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Fri, 27 Sep 2024 12:26:53 +0200
Subject: [PATCH 21/24] Update validation

---
 .../Wasp/Generator/ExternalConfig/Common.hs   |  3 ++
 .../Generator/ExternalConfig/PackageJson.hs   | 20 ++++-----
 .../Wasp/Generator/ExternalConfig/TsConfig.hs | 45 ++++++++++++-------
 waspc/waspc.cabal                             |  1 +
 4 files changed, 41 insertions(+), 28 deletions(-)
 create mode 100644 waspc/src/Wasp/Generator/ExternalConfig/Common.hs

diff --git a/waspc/src/Wasp/Generator/ExternalConfig/Common.hs b/waspc/src/Wasp/Generator/ExternalConfig/Common.hs
new file mode 100644
index 0000000000..3f49f1782b
--- /dev/null
+++ b/waspc/src/Wasp/Generator/ExternalConfig/Common.hs
@@ -0,0 +1,3 @@
+module Wasp.Generator.ExternalConfig.Common (ErrorMsg) where
+
+type ErrorMsg = String
diff --git a/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
index 0473d3b5d0..304a035fa5 100644
--- a/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
@@ -6,20 +6,18 @@ where
 import qualified Data.Map as M
 import qualified Wasp.ExternalConfig.PackageJson as P
 import Wasp.Generator.Common (prismaVersion)
+import Wasp.Generator.ExternalConfig.Common (ErrorMsg)
 import Wasp.Generator.WebAppGenerator.Common (reactRouterVersion)
 
-validatePackageJson :: P.PackageJson -> IO [String]
+validatePackageJson :: P.PackageJson -> [ErrorMsg]
 validatePackageJson packageJson =
-  return $
-    concat
-      [ -- Wasp needs the Wasp SDK to be installed in the project.
-        validate ("wasp", "file:.wasp/out/sdk/wasp", IsListedWithExactVersion),
-        -- Wrong version of Prisma will break the generated code.
-        validate ("prisma", show prismaVersion, IsListedAsDevWithExactVersion),
-        -- Installing the wrong version of "react-router-dom" can make users believe that they
-        -- can use features that are not available in the version that Wasp supports.
-        validate ("react-router-dom", show reactRouterVersion, HasExactVersionIfListed)
-      ]
+  concat
+    [ validate ("wasp", "file:.wasp/out/sdk/wasp", IsListedWithExactVersion),
+      validate ("prisma", show prismaVersion, IsListedAsDevWithExactVersion),
+      -- Installing the wrong version of "react-router-dom" can make users believe that they
+      -- can use features that are not available in the version that Wasp supports.
+      validate ("react-router-dom", show reactRouterVersion, HasExactVersionIfListed)
+    ]
   where
     validate = validateDep packageJson
 
diff --git a/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
index f3f9a04c13..d41d051872 100644
--- a/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
@@ -6,32 +6,37 @@ module Wasp.Generator.ExternalConfig.TsConfig
 where
 
 import qualified Wasp.ExternalConfig.TsConfig as T
+import Wasp.Generator.ExternalConfig.Common (ErrorMsg)
 
-validateTsConfig :: T.TsConfig -> IO [String]
+validateTsConfig :: T.TsConfig -> [ErrorMsg]
 validateTsConfig tsConfig =
-  return $
-    concat
-      [ validateRequiredFieldInCompilerOptions "module" "esnext" T._module,
-        validateRequiredFieldInCompilerOptions "target" "esnext" T.target,
-        validateRequiredFieldInCompilerOptions "moduleResolution" "bundler" T.moduleResolution,
-        validateRequiredFieldInCompilerOptions "jsx" "preserve" T.jsx,
-        validateRequiredFieldInCompilerOptions "strict" True T.strict,
-        validateRequiredFieldInCompilerOptions "esModuleInterop" True T.esModuleInterop,
-        validateRequiredFieldInCompilerOptions "lib" ["dom", "dom.iterable", "esnext"] T.lib,
-        validateRequiredFieldInCompilerOptions "allowJs" True T.allowJs,
-        validateRequiredFieldInCompilerOptions "typeRoots" ["node_modules/@testing-library", "node_modules/@types"] T.typeRoots,
-        validateRequiredFieldInCompilerOptions "outDir" ".wasp/phantom" T.outDir
-      ]
+  concat
+    [ validateRequiredFieldInCompilerOptions "module" "esnext" T._module,
+      validateRequiredFieldInCompilerOptions "target" "esnext" T.target,
+      validateRequiredFieldInCompilerOptions "moduleResolution" "bundler" T.moduleResolution,
+      validateRequiredFieldInCompilerOptions "jsx" "preserve" T.jsx,
+      validateRequiredFieldInCompilerOptions "strict" True T.strict,
+      validateRequiredFieldInCompilerOptions "esModuleInterop" True T.esModuleInterop,
+      validateRequiredFieldInCompilerOptions "lib" ["dom", "dom.iterable", "esnext"] T.lib,
+      validateRequiredFieldInCompilerOptions "allowJs" True T.allowJs,
+      validateRequiredFieldInCompilerOptions "typeRoots" ["node_modules/@testing-library", "node_modules/@types"] T.typeRoots,
+      validateRequiredFieldInCompilerOptions "outDir" ".wasp/phantom" T.outDir
+    ]
   where
     validateRequiredFieldInCompilerOptions fieldName expectedValue getFieldValue = case getFieldValue compilerOptionsFields of
       Just actualValue -> validateFieldValue ("compilerOptions." ++ fieldName) expectedValue actualValue
       Nothing -> [missingFieldErrorMessage]
       where
-        missingFieldErrorMessage = unwords ["The", show fieldName, "field is missing in tsconfig.json. Expected value:", showAsJsValue expectedValue ++ "."]
+        missingFieldErrorMessage =
+          unwords
+            [ "The",
+              show fieldName,
+              "field is missing in tsconfig.json. Expected value:",
+              showAsJsValue expectedValue ++ "."
+            ]
 
     compilerOptionsFields = T.compilerOptions tsConfig
 
--- | Haskell type that implements ShowJS is a type whose values can be mapped to Javascript values (their string representation).
 class IsJavascriptValue a where
   showAsJsValue :: a -> String
 
@@ -53,4 +58,10 @@ validateFieldValue fieldName expectedValue actualValue =
     then []
     else [invalidValueErrorMessage]
   where
-    invalidValueErrorMessage = unwords ["Invalid value for the", show fieldName, "field in tsconfig.json file, expected value:", showAsJsValue expectedValue ++ "."]
+    invalidValueErrorMessage =
+      unwords
+        [ "Invalid value for the",
+          show fieldName,
+          "field in tsconfig.json file, expected value:",
+          showAsJsValue expectedValue ++ "."
+        ]
diff --git a/waspc/waspc.cabal b/waspc/waspc.cabal
index b8e1b353d7..17559a2b6d 100644
--- a/waspc/waspc.cabal
+++ b/waspc/waspc.cabal
@@ -279,6 +279,7 @@ library
     Wasp.Generator.DbGenerator.Operations
     Wasp.Generator.DockerGenerator
     Wasp.Generator.ExternalCodeGenerator.Common
+    Wasp.Generator.ExternalConfig.Common
     Wasp.Generator.ExternalConfig.PackageJson
     Wasp.Generator.ExternalConfig.TsConfig
     Wasp.Generator.FileDraft

From 6a7ba87e09298a56aa2c553d217e66adb9a1a224 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Fri, 27 Sep 2024 12:32:33 +0200
Subject: [PATCH 22/24] PR comments

---
 waspc/src/Wasp/ExternalConfig/PackageJson.hs  |  5 +-
 .../Generator/ExternalConfig/PackageJson.hs   | 10 ++--
 .../Wasp/Generator/ExternalConfig/TsConfig.hs | 56 +++++++++----------
 3 files changed, 35 insertions(+), 36 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
index 8e1f1fd033..fddb9b9268 100644
--- a/waspc/src/Wasp/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/ExternalConfig/PackageJson.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE DeriveAnyClass #-}
 {-# LANGUAGE DeriveGeneric #-}
 
 module Wasp.ExternalConfig.PackageJson
@@ -22,7 +23,7 @@ data PackageJson = PackageJson
     dependencies :: !DependenciesMap,
     devDependencies :: !DependenciesMap
   }
-  deriving (Show, Generic)
+  deriving (Show, Generic, FromJSON)
 
 getDependencies :: PackageJson -> [Dependency]
 getDependencies packageJson = D.fromList $ M.toList $ dependencies packageJson
@@ -35,5 +36,3 @@ type DependenciesMap = Map PackageName PackageVersion
 type PackageName = String
 
 type PackageVersion = String
-
-instance FromJSON PackageJson
diff --git a/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
index 304a035fa5..c8e8952443 100644
--- a/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/Generator/ExternalConfig/PackageJson.hs
@@ -12,19 +12,19 @@ import Wasp.Generator.WebAppGenerator.Common (reactRouterVersion)
 validatePackageJson :: P.PackageJson -> [ErrorMsg]
 validatePackageJson packageJson =
   concat
-    [ validate ("wasp", "file:.wasp/out/sdk/wasp", IsListedWithExactVersion),
-      validate ("prisma", show prismaVersion, IsListedAsDevWithExactVersion),
+    [ validate ("wasp", "file:.wasp/out/sdk/wasp") IsListedWithExactVersion,
+      validate ("prisma", show prismaVersion) IsListedAsDevWithExactVersion,
       -- Installing the wrong version of "react-router-dom" can make users believe that they
       -- can use features that are not available in the version that Wasp supports.
-      validate ("react-router-dom", show reactRouterVersion, HasExactVersionIfListed)
+      validate ("react-router-dom", show reactRouterVersion) HasExactVersionIfListed
     ]
   where
     validate = validateDep packageJson
 
 data PackageValidationType = IsListedWithExactVersion | IsListedAsDevWithExactVersion | HasExactVersionIfListed
 
-validateDep :: P.PackageJson -> (P.PackageName, P.PackageVersion, PackageValidationType) -> [String]
-validateDep packageJson (packageName, expectedPackageVersion, validationType) = case validationType of
+validateDep :: P.PackageJson -> (P.PackageName, P.PackageVersion) -> PackageValidationType -> [String]
+validateDep packageJson (packageName, expectedPackageVersion) = \case
   IsListedWithExactVersion -> checkDeps [P.dependencies packageJson] [requiredPackageMessage "dependencies"]
   IsListedAsDevWithExactVersion -> checkDeps [P.devDependencies packageJson] [requiredPackageMessage "devDependencies"]
   HasExactVersionIfListed -> checkDeps [P.dependencies packageJson, P.devDependencies packageJson] []
diff --git a/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
index d41d051872..ab3d3e4001 100644
--- a/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/Generator/ExternalConfig/TsConfig.hs
@@ -8,6 +8,21 @@ where
 import qualified Wasp.ExternalConfig.TsConfig as T
 import Wasp.Generator.ExternalConfig.Common (ErrorMsg)
 
+class IsJavascriptValue a where
+  showAsJsValue :: a -> String
+
+instance IsJavascriptValue String where
+  showAsJsValue = show
+
+instance IsJavascriptValue [String] where
+  showAsJsValue = show
+
+instance IsJavascriptValue Bool where
+  showAsJsValue True = "true"
+  showAsJsValue False = "false"
+
+type FieldName = String
+
 validateTsConfig :: T.TsConfig -> [ErrorMsg]
 validateTsConfig tsConfig =
   concat
@@ -37,31 +52,16 @@ validateTsConfig tsConfig =
 
     compilerOptionsFields = T.compilerOptions tsConfig
 
-class IsJavascriptValue a where
-  showAsJsValue :: a -> String
-
-instance IsJavascriptValue String where
-  showAsJsValue = show
-
-instance IsJavascriptValue [String] where
-  showAsJsValue = show
-
-instance IsJavascriptValue Bool where
-  showAsJsValue True = "true"
-  showAsJsValue False = "false"
-
-type FieldName = String
-
-validateFieldValue :: (Eq value, IsJavascriptValue value) => FieldName -> value -> value -> [String]
-validateFieldValue fieldName expectedValue actualValue =
-  if actualValue == expectedValue
-    then []
-    else [invalidValueErrorMessage]
-  where
-    invalidValueErrorMessage =
-      unwords
-        [ "Invalid value for the",
-          show fieldName,
-          "field in tsconfig.json file, expected value:",
-          showAsJsValue expectedValue ++ "."
-        ]
+    validateFieldValue :: (Eq value, IsJavascriptValue value) => FieldName -> value -> value -> [String]
+    validateFieldValue fieldName expectedValue actualValue =
+      if actualValue == expectedValue
+        then []
+        else [invalidValueErrorMessage]
+      where
+        invalidValueErrorMessage =
+          unwords
+            [ "Invalid value for the",
+              show fieldName,
+              "field in tsconfig.json file, expected value:",
+              showAsJsValue expectedValue ++ "."
+            ]

From 684d19ea6d690a87fa904e67780d18d50df2a595 Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Fri, 27 Sep 2024 13:06:18 +0200
Subject: [PATCH 23/24] Inline validateToEither

---
 waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs | 7 ++++---
 waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs    | 7 ++++---
 waspc/src/Wasp/Util.hs                               | 7 -------
 3 files changed, 8 insertions(+), 13 deletions(-)

diff --git a/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs b/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs
index a46fd9e800..562285a8b6 100644
--- a/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs
+++ b/waspc/src/Wasp/Project/ExternalConfig/PackageJson.hs
@@ -4,7 +4,7 @@ module Wasp.Project.ExternalConfig.PackageJson
   )
 where
 
-import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
+import Control.Monad.Except (ExceptT (ExceptT), MonadError (throwError), runExceptT)
 import qualified Data.Aeson as Aeson
 import Data.Either.Extra (maybeToEither)
 import StrongPath (Abs, Dir, File, Path', toFilePath)
@@ -16,14 +16,15 @@ import Wasp.Project.Common
     findFileInWaspProjectDir,
     packageJsonInWaspProjectDir,
   )
-import Wasp.Util (validateToEither)
 import qualified Wasp.Util.IO as IOUtil
 
 analyzePackageJsonFile :: Path' Abs (Dir WaspProjectDir) -> IO (Either [String] P.PackageJson)
 analyzePackageJsonFile waspProjectDir = runExceptT $ do
   packageJsonFile <- ExceptT findPackageJsonFileOrError
   packageJson <- ExceptT $ readPackageJsonFile packageJsonFile
-  ExceptT $ validateToEither validatePackageJson packageJson
+  case validatePackageJson packageJson of
+    [] -> return packageJson
+    errors -> throwError errors
   where
     findPackageJsonFileOrError = maybeToEither [fileNotFoundMessage] <$> findPackageJsonFile waspProjectDir
     fileNotFoundMessage = "Couldn't find the package.json file in the " ++ toFilePath waspProjectDir ++ " directory"
diff --git a/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs
index 2ca9027d31..8693241a9b 100644
--- a/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/Project/ExternalConfig/TsConfig.hs
@@ -3,7 +3,7 @@ module Wasp.Project.ExternalConfig.TsConfig
   )
 where
 
-import Control.Monad.Except (ExceptT (ExceptT), runExceptT)
+import Control.Monad.Except (ExceptT (ExceptT), runExceptT, throwError)
 import qualified Data.ByteString.Lazy.UTF8 as BS
 import Data.Either.Extra (maybeToEither)
 import StrongPath (Abs, Dir, File, Path', toFilePath)
@@ -15,7 +15,6 @@ import Wasp.Project.Common
     findFileInWaspProjectDir,
     tsConfigInWaspProjectDir,
   )
-import Wasp.Util (validateToEither)
 import qualified Wasp.Util.IO as IOUtil
 import Wasp.Util.Json (parseJsonWithComments)
 
@@ -23,7 +22,9 @@ analyzeTsConfigFile :: Path' Abs (Dir WaspProjectDir) -> IO (Either [String] T.T
 analyzeTsConfigFile waspDir = runExceptT $ do
   tsConfigFile <- ExceptT findTsConfigOrError
   tsConfig <- ExceptT $ readTsConfigFile tsConfigFile
-  ExceptT $ validateToEither validateTsConfig tsConfig
+  case validateTsConfig tsConfig of
+    [] -> return tsConfig
+    errors -> throwError errors
   where
     findTsConfigOrError = maybeToEither [fileNotFoundMessage] <$> findTsConfigFile waspDir
     fileNotFoundMessage = "Couldn't find the tsconfig.json file in the " ++ toFilePath waspDir ++ " directory"
diff --git a/waspc/src/Wasp/Util.hs b/waspc/src/Wasp/Util.hs
index 1907da3ec4..9cedb4e0d7 100644
--- a/waspc/src/Wasp/Util.hs
+++ b/waspc/src/Wasp/Util.hs
@@ -40,7 +40,6 @@ module Wasp.Util
     trim,
     secondsToMicroSeconds,
     findDuplicateElems,
-    validateToEither,
   )
 where
 
@@ -271,9 +270,3 @@ secondsToMicroSeconds = (* 1000000)
 
 findDuplicateElems :: Ord a => [a] -> [a]
 findDuplicateElems = map head . filter ((> 1) . length) . group . sort
-
-validateToEither :: (Monad m) => (a -> m [String]) -> a -> m (Either [String] a)
-validateToEither validateFn input =
-  validateFn input >>= \case
-    [] -> return $ Right input
-    errors -> return $ Left errors

From a1e68517b1095246103bf8f9614b0ce4ca1e5f6f Mon Sep 17 00:00:00 2001
From: Mihovil Ilakovac <mihovil@ilakovac.com>
Date: Fri, 27 Sep 2024 13:08:24 +0200
Subject: [PATCH 24/24] Cleanup

---
 waspc/src/Wasp/ExternalConfig/TsConfig.hs | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/waspc/src/Wasp/ExternalConfig/TsConfig.hs b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
index d4d10176f5..fe443b9647 100644
--- a/waspc/src/Wasp/ExternalConfig/TsConfig.hs
+++ b/waspc/src/Wasp/ExternalConfig/TsConfig.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE DeriveAnyClass #-}
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE FlexibleInstances #-}
 
@@ -18,9 +19,7 @@ import GHC.Generics (Generic)
 data TsConfig = TsConfig
   { compilerOptions :: !CompilerOptions
   }
-  deriving (Show, Generic)
-
-instance FromJSON TsConfig
+  deriving (Show, Generic, FromJSON)
 
 data CompilerOptions = CompilerOptions
   { _module :: !(Maybe String),