Add tests

spec/tapioca/cli/annotations_spec.rb

@@ -27,6 +27,7 @@ class AnnotationsTest < SpecWithProject
         OUT
 
         assert_success_status(result)
+        refute(File.directory?(@project.absolute_path("sorbet/rbi/annotations")))
 
         repo.destroy
       end
@@ -94,6 +95,9 @@ class AnnotationForRBI; end
           class AnnotationForSpoom; end
         RBI
 
+        assert_project_file_equal("sorbet/rbi/annotations/.gitattributes", <<~CONTENT)
+          **/*.rbi linguist-vendored=true
+        CONTENT
         refute_project_file_exist("sorbet/rbi/annotations/foo.rbi")
         assert_success_status(result)
 

spec/tapioca/cli/dsl_spec.rb

@@ -72,6 +72,40 @@ def self.application
           @project.remove("sorbet/rbi/dsl")
         end
 
+        it "must generate a .gitattributes file in the output folder" do
+          @project.write("lib/post.rb", <<~RB)
+            require "smart_properties"
+
+            class Post
+              include SmartProperties
+              property :title, accepts: String
+            end
+          RB
+
+          result = @project.tapioca("dsl Post --outdir output")
+
+          assert_empty_stderr(result)
+          assert_success_status(result)
+
+          assert_project_file_equal("output/.gitattributes", <<~CONTENT)
+            **/*.rbi linguist-generated=true
+          CONTENT
+        ensure
+          @project.remove("output")
+        end
+
+        it "must not generate a .gitattributes file if the output folder is not created" do
+          result = @project.tapioca("dsl --outdir output")
+
+          assert_equal(<<~ERR, result.err)
+            No classes/modules can be matched for RBI generation.
+            Please check that the requested classes/modules include processable DSL methods.
+          ERR
+          refute_project_file_exist("output/.gitattributes")
+        ensure
+          @project.remove("output")
+        end
+
         it "respects the Gemfile and Gemfile.lock" do
           gem = mock_gem("foo", "1.0.0") do
             write("lib/foo.rb", <<~RB)

spec/tapioca/cli/gem_spec.rb

@@ -213,6 +213,52 @@ class << self
           project.remove("config/application.rb")
         end
 
+        it "must generate a .gitattributes file in the output folder" do
+          foo = mock_gem("foo", "0.0.1") do
+            write("lib/foo.rb", FOO_RB)
+          end
+
+          @project.require_mock_gem(foo)
+          @project.bundle_install
+          result = @project.tapioca("gem foo --outdir output")
+
+          assert_stdout_includes(result, <<~OUT)
+            Compiled foo
+          OUT
+
+          assert_empty_stderr(result)
+          assert_success_status(result)
+
+          assert_project_file_equal("output/.gitattributes", <<~CONTENT)
+            **/*.rbi linguist-generated=true
+          CONTENT
+        ensure
+          @project.remove("output")
+        end
+
+        it "must not generate a .gitattributes file if the output folder is not created" do
+          foo = mock_gem("foo", "0.0.1") do
+            write("lib/foo.rb", FOO_RB)
+          end
+
+          @project.require_mock_gem(foo)
+          @project.bundle_install
+
+          # Generate for `foo` but exclude it as well, so that we don't create the output folder
+          result = @project.tapioca("gem foo --outdir output --exclude foo")
+
+          assert_stdout_includes(result, <<~OUT)
+            Nothing to do.
+          OUT
+
+          assert_empty_stderr(result)
+          assert_success_status(result)
+
+          refute_project_file_exist("output/.gitattributes")
+        ensure
+          @project.remove("output")
+        end
+
         it "must generate a single gem RBI" do
           foo = mock_gem("foo", "0.0.1") do
             write("lib/foo.rb", FOO_RB)
@@ -1598,6 +1644,20 @@ def baz; end
           @project.remove("../gems")
         end
 
+        it "must generate a .gitattributes file in the output folder" do
+          result = @project.tapioca("gem --outdir output")
+
+          assert_stdout_includes(result, "create  output/[email protected]")
+          assert_empty_stderr(result)
+          assert_success_status(result)
+
+          assert_project_file_equal("output/.gitattributes", <<~CONTENT)
+            **/*.rbi linguist-generated=true
+          CONTENT
+        ensure
+          @project.remove("output")
+        end
+
         it "must perform no operations if everything is up-to-date" do
           @project.write("sorbet/rbi/gems/[email protected]")
           @project.write("sorbet/rbi/gems/[email protected]")