Make tests pass

USAGE.md

@@ -21,6 +21,7 @@
   * [Understanding how to respond to new violations](#understanding-how-to-respond-to-new-violations)
 * [Recording existing violations](#recording-existing-violations)
   * [Understanding the list of deprecated references](#understanding-the-list-of-deprecated-references)
+* [Loading extensions](#loading-extensions)
 
 ## What problem does Packwerk solve?
 
@@ -275,3 +276,16 @@ Above is an example of a constant violation entry in `deprecated_references.yml`
 * `components/merchant/app/public/merchant/generate_order.rb` - path to the file containing the violated constant
 
 Violations exist within the package that makes a violating reference. This means privacy violations of your package can be found listed in `deprecated_references.yml` files in the packages with the reference to a private constant.
+
+# Loading Extensions
+
+You can optionally specify ruby files that you'd like to be loaded with `packwerk` by specifying a `require` directive in `packwerk.yml`:
+```yml
+require:
+  - ./path/to/file.rb
+  - my_gem
+```
+
+`packwerk` will directly call `require` with these paths.
+You can prefix local files with a dot to define them relative to `packwerk.yml`, or you can use absolute paths.
+You can also reference the name of a gem.

lib/packwerk.rb

@@ -22,6 +22,7 @@ module Packwerk
   autoload :ConstantNameInspector
   autoload :ConstNodeInspector
   autoload :DeprecatedReferences
+  autoload :ExtensionLoader
   autoload :FileProcessor
   autoload :FilesForProcessing
   autoload :Graph

lib/packwerk/configuration.rb

@@ -49,6 +49,12 @@ def initialize(configs = {}, config_path: nil)
       @cache_directory = Pathname.new(configs["cache_directory"] || "tmp/cache/packwerk")
       @config_path = config_path
 
+      if configs.key?("require")
+        configs["require"].each do |require_directive|
+          ExtensionLoader.load(require_directive, @root_path)
+        end
+      end
+
       if configs["load_paths"]
         warning = <<~WARNING
           DEPRECATION WARNING: The 'load_paths' key in `packwerk.yml` is deprecated.

lib/packwerk/extension_loader.rb

@@ -0,0 +1,24 @@
+# typed: strict
+# frozen_string_literal: true
+
+module Packwerk
+  # This class handles loading extensions to packwerk using the `require` directive
+  # in the `packwerk.yml` configuration.
+  class ExtensionLoader
+    class << self
+      extend T::Sig
+      sig { params(require_directive: String, config_dir_path: String).void }
+      def load(require_directive, config_dir_path)
+        # We want to transform the require directive to behave differently
+        # if it's a specific local file being required versus a gem
+        if require_directive.start_with?(".")
+          require File.join(config_dir_path, require_directive)
+        else
+          require require_directive
+        end
+      end
+    end
+  end
+
+  private_constant :ExtensionLoader
+end

test/fixtures/skeleton/config/my_extension.rb

@@ -0,0 +1,2 @@
+module MySpecialExtension
+end

test/fixtures/skeleton/packwerk.yml

@@ -4,3 +4,6 @@ include:
 exclude:
   - "**/temp.rb"
 parallel: false
+require:
+  - ./config/my_extension.rb
+  - pathname

test/integration/custom_executable_test.rb

@@ -80,8 +80,8 @@ class CustomExecutableTest < Minitest::Test
 
         deprecated_reference_content_after_update = read_deprecated_references
         expected_output = <<~EOS
-          📦 Packwerk is inspecting 13 files
-          \\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.
+          📦 Packwerk is inspecting 14 files
+          \\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.
           📦 Finished in \\d+\\.\\d+ seconds
 
           No offenses detected
@@ -115,8 +115,8 @@ class CustomExecutableTest < Minitest::Test
           deprecated_reference_content_after_update =
             read_deprecated_references.reject { |k, _v| k.match?(timeline_deprecated_reference_path) }
           expected_output = <<~EOS
-            📦 Packwerk is inspecting 14 files
-            \\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.
+            📦 Packwerk is inspecting 15 files
+            \\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.\\.
             📦 Finished in \\d+\\.\\d+ seconds
 
             No offenses detected