Add JSONC support

README.md

@@ -14,8 +14,6 @@ npm init svelte@next
 
 Once that is set up, run this command in your project directory to set up Jest:
 
-> ❗️ __When running with TypeScript support enabled, remove comments within `tsconfig.json` or the adder will fail. This is a known limitation of [Preset](https://usepreset.dev/), as it relies upon JSON.parse.__
-
 ```sh
 npx apply rossyman/svelte-add-jest # --no-ssh
 ```

package.json

@@ -1,7 +1,7 @@
 {
   "private": true,
   "name": "@rossyman/svelte-add-jest",
-  "version": "1.1.1",
+  "version": "1.1.2",
   "description": "SvelteKit adder for Jest unit testing",
   "license": "MIT",
   "keywords": [
@@ -20,6 +20,7 @@
   ],
   "preset": "preset.ts",
   "devDependencies": {
-    "apply": "^0.2.13"
+    "apply": "^0.2.13",
+    "comment-json": "^4.1.0"
   }
 }

preset.ts

@@ -1,3 +1,4 @@
+import { assign, parse, stringify } from 'comment-json';
 import { Preset, color } from 'apply';
 
 type Dependencies = {
@@ -187,12 +188,10 @@ class SvelteJestAdder extends Adder {
       .withTitle('Enabling Jest DOM Support')
       .if(() => this.getConfiguration('jest-dom'));
 
-    Preset
-      .editJson('tsconfig.json').merge({
-        exclude: ['src/**/*.spec.ts']
-      })
-      .withTitle('Modifying TypeScript config for project')
-      .if(() => this.getConfiguration('ts'));
+    Preset.edit('tsconfig.json').update((content) => 
+      stringify(assign(parse(content), { exclude: ['src/**/*.spec.ts'] }), null, 4))
+        .withTitle('Modifying TypeScript config for project')
+        .if(() => this.getConfiguration('ts'));
 
     Preset
       .editJson('jest.config.json').merge({