Start generating gitattributes file for generated and vendored RBI files

This commit adds a `.gitattributes` file to the output folder that marks all RBI files as `generated` for `dsl` and `gem` RBI generation commands. It also add a `.gitattributes` file to the output folder that marks all RBI files as `vendored` for `annotations` command.

lib/tapioca/commands/annotations.rb

@@ -23,6 +23,7 @@ def initialize(
         typed_overrides: {}
       )
         super()
+        @outpath = T.let(Pathname.new(DEFAULT_ANNOTATIONS_DIR), Pathname)
         @central_repo_root_uris = central_repo_root_uris
         @auth = auth
         @netrc_file = netrc_file
@@ -38,8 +39,11 @@ def initialize(
       def execute
         @indexes = fetch_indexes
         project_gems = list_gemfile_gems
+
         remove_expired_annotations(project_gems)
         fetch_annotations(project_gems)
+      ensure
+        GitAttributes.create_vendored_attribute_file(@outpath)
       end
 
       sig { returns(T::Array[String]) }
@@ -56,7 +60,7 @@ def list_gemfile_gems
       def remove_expired_annotations(project_gems)
         say("Removing annotations for gems that have been removed... ", [:blue, :bold])
 
-        annotations = Pathname.glob("#{DEFAULT_ANNOTATIONS_DIR}/*.rbi").map { |f| f.basename(".*").to_s }
+        annotations = Pathname.glob(@outpath.join("*.rbi")).map { |f| f.basename(".*").to_s }
         expired = annotations - project_gems
 
         if expired.empty?
@@ -67,7 +71,7 @@ def remove_expired_annotations(project_gems)
         say("\n")
         expired.each do |gem_name|
           say("\n")
-          path = "#{DEFAULT_ANNOTATIONS_DIR}/#{gem_name}.rbi"
+          path = @outpath.join("#{gem_name}.rbi")
           remove_file(path)
         end
         say("\nDone\n\n", :green)
@@ -140,10 +144,8 @@ def fetch_annotation(repo_uris, gem_name)
         content = apply_typed_override(gem_name, content)
         content = add_header(gem_name, content)
 
-        dir = DEFAULT_ANNOTATIONS_DIR
-        FileUtils.mkdir_p(dir)
         say("\n  Fetched #{set_color(gem_name, :yellow, :bold)}", :green)
-        create_file("#{dir}/#{gem_name}.rbi", content)
+        create_file(@outpath.join("#{gem_name}.rbi"), content)
       end
 
       sig { params(repo_uri: String, path: String).returns(T.nilable(String)) }

lib/tapioca/commands/dsl_generate.rb

@@ -32,6 +32,8 @@ def execute
 
         say("All operations performed in working directory.", [:green, :bold])
         say("Please review changes and commit them.", [:green, :bold])
+      ensure
+        GitAttributes.create_generated_attribute_file(@outpath)
       end
     end
   end

lib/tapioca/commands/gem_generate.rb

@@ -43,6 +43,8 @@ def execute
         else
           say("No operations performed, all RBIs are up-to-date.", [:green, :bold])
         end
+      ensure
+        GitAttributes.create_generated_attribute_file(@outpath)
       end
     end
   end

lib/tapioca/commands/gem_sync.rb

@@ -29,6 +29,8 @@ def execute
         end
 
         puts
+      ensure
+        GitAttributes.create_generated_attribute_file(@outpath)
       end
     end
   end

lib/tapioca/helpers/git_attributes.rb

@@ -0,0 +1,34 @@
+# typed: strict
+# frozen_string_literal: true
+
+class GitAttributes
+  class << self
+    extend T::Sig
+
+    sig { params(path: Pathname).void }
+    def create_generated_attribute_file(path)
+      create_gitattributes_file(path, <<~CONTENT)
+        **/*.rbi linguist-generated=true
+      CONTENT
+    end
+
+    sig { params(path: Pathname).void }
+    def create_vendored_attribute_file(path)
+      create_gitattributes_file(path, <<~CONTENT)
+        **/*.rbi linguist-vendored=true
+      CONTENT
+    end
+
+    private
+
+    sig { params(path: Pathname, content: String).void }
+    def create_gitattributes_file(path, content)
+      # We don't want to start creating folders, just to write
+      # the `.gitattributes` file. So, if the folder doesn't
+      # exist, we just return.
+      return unless path.exist?
+
+      File.write(path.join(".gitattributes"), content)
+    end
+  end
+end

lib/tapioca/internal.rb

@@ -28,6 +28,7 @@
 require "tapioca/runtime/dynamic_mixin_compiler"
 require "tapioca/helpers/gem_helper"
 
+require "tapioca/helpers/git_attributes"
 require "tapioca/helpers/sorbet_helper"
 require "tapioca/helpers/rbi_helper"
 require "tapioca/sorbet_ext/backcompat_patches"