Set up Zeitwerk for code loading (#1)

hanami-db.gemspec

@@ -1,8 +1,10 @@
 # frozen_string_literal: true
 
+require_relative "lib/hanami/db/version"
+
 Gem::Specification.new do |spec|
   spec.name = "hanami-db"
-  spec.version = "0.0.0"
+  spec.version = Hanami::DB::VERSION
   spec.authors = ["Hanami team"]
   spec.email = ["[email protected]"]
   spec.summary = "The database layer for Hanami apps"

lib/hanami/db.rb

@@ -1,6 +1,26 @@
 # frozen_string_literal: true
 
+require "zeitwerk"
+
 module Hanami
   module DB
+    require_relative "db/gem_inflector"
+
+    # @api private
+    # @since 2.2.0
+    def self.loader
+      @loader ||= Zeitwerk::Loader.new.tap do |loader|
+        root = File.expand_path("..", __dir__)
+
+        loader.inflector = GemInflector.new("#{root}/hanami/db.rb")
+        loader.tag = "hanami-db"
+        loader.push_dir root
+        loader.ignore(
+          "#{root}/hanami-db.rb",
+          "#{root}/hanami/db/gem_inflector.rb"
+        )
+      end
+    end
+    loader.setup
   end
 end

lib/hanami/db/gem_inflector.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+module Hanami
+  module DB
+    # @api private
+    class GemInflector < Zeitwerk::GemInflector
+      def camelize(basename, _abspath)
+        return "DB" if basename == "db"
+
+        super
+      end
+    end
+  end
+end

lib/hanami/db/version.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+module Hanami
+  module DB
+    VERSION = "0.0.0"
+  end
+end