Merge pull request #41067 from eugeneius/relative_file_fixture_path

Fix fixture_file_upload deprecation with relative file_fixture_path

actionpack/lib/action_dispatch/testing/test_process.rb

@@ -29,7 +29,7 @@ def fixture_file_upload(path, mime_type = nil, binary = false)
               haven't set yet. Set `file_fixture_path` to discard this warning.
             EOM
           elsif path.exist?
-            non_deprecated_path = path.relative_path_from(Pathname(self.class.file_fixture_path))
+            non_deprecated_path = Pathname(File.absolute_path(path)).relative_path_from(Pathname(File.absolute_path(self.class.file_fixture_path)))
             ActiveSupport::Deprecation.warn(<<~EOM)
               Passing a path to `fixture_file_upload` relative to `fixture_path` is deprecated.
               In Rails 6.2, the path needs to be relative to `file_fixture_path`.

actionpack/test/controller/test_case_test.rb

@@ -960,6 +960,19 @@ def test_fixture_file_upload_relative_to_fixture_path
     end
   end
 
+  def test_fixture_file_upload_relative_to_fixture_path_with_relative_file_fixture_path
+    TestCaseTest.stub :fixture_path, File.expand_path("../fixtures", __dir__) do
+      TestCaseTest.stub :file_fixture_path, "test/fixtures/multipart" do
+        expected = "`fixture_file_upload(\"multipart/ruby_on_rails.jpg\")` to `fixture_file_upload(\"ruby_on_rails.jpg\")`"
+
+        assert_deprecated(expected) do
+          uploaded_file = fixture_file_upload("multipart/ruby_on_rails.jpg", "image/jpg")
+          assert_equal File.open("#{FILES_DIR}/ruby_on_rails.jpg", READ_PLAIN).read, uploaded_file.read
+        end
+      end
+    end
+  end
+
   def test_fixture_file_upload_ignores_fixture_path_given_full_path
     TestCaseTest.stub :fixture_path, __dir__ do
       uploaded_file = fixture_file_upload("#{FILES_DIR}/ruby_on_rails.jpg", "image/jpg")