From c65cc65c3292076157d6ec9f767d36f9efe8d25f Mon Sep 17 00:00:00 2001
From: Sean Doyle <sean.p.doyle24@gmail.com>
Date: Sun, 5 Jan 2025 01:13:25 -0500
Subject: [PATCH] Support XML and JSON inflector acronyms

Related to https://github.com/rails/activeresource/pull/361

Add special-case treatment of JSON and XML acronyms by declaring aliases
for the `JsonFormat` and `XmlFormat` constants.

In addition to the aliases, this commit also includes test coverage to
cover existing behavior.

The original PR included a comment citing that
`ActiveSupport::Inflector::Inflections#clear` was not working as
expected. It was resolved by [a76344f][], which was merged into `main`
prior to the `7.0.0` release. Since the CI matrix currently includes
`7-0-stable` as the minimum version, the code can rely on the resolved
behavior.

[a76344f]: https://github.com/rails/rails/commit/a76344ffc5a308e0ad6105fde921990f57fa0ea9
---
 lib/active_resource/formats/json_format.rb |  2 +
 lib/active_resource/formats/xml_format.rb  |  2 +
 test/cases/formats_test.rb                 | 44 ++++++++++++++++++++++
 3 files changed, 48 insertions(+)
 create mode 100644 test/cases/formats_test.rb

diff --git a/lib/active_resource/formats/json_format.rb b/lib/active_resource/formats/json_format.rb
index 67795f95e3..7898e67335 100644
--- a/lib/active_resource/formats/json_format.rb
+++ b/lib/active_resource/formats/json_format.rb
@@ -24,5 +24,7 @@ def decode(json)
         Formats.remove_root(ActiveSupport::JSON.decode(json))
       end
     end
+
+    JSONFormat = JsonFormat
   end
 end
diff --git a/lib/active_resource/formats/xml_format.rb b/lib/active_resource/formats/xml_format.rb
index 5fbf967e08..daac245d44 100644
--- a/lib/active_resource/formats/xml_format.rb
+++ b/lib/active_resource/formats/xml_format.rb
@@ -23,5 +23,7 @@ def decode(xml)
         Formats.remove_root(Hash.from_xml(xml))
       end
     end
+
+    XMLFormat = XmlFormat
   end
 end
diff --git a/test/cases/formats_test.rb b/test/cases/formats_test.rb
new file mode 100644
index 0000000000..7d11c5d8af
--- /dev/null
+++ b/test/cases/formats_test.rb
@@ -0,0 +1,44 @@
+# frozen_string_literal: true
+
+require "abstract_unit"
+
+class FormatsTest < ActiveSupport::TestCase
+  def test_json_format_uses_camelcase
+    assert_equal ActiveResource::Formats::JsonFormat, ActiveResource::Formats[:json]
+  end
+
+  def test_xml_format_uses_camelcase
+    assert_equal ActiveResource::Formats::XmlFormat, ActiveResource::Formats[:xml]
+  end
+
+  def test_custom_format_uses_camelcase
+    klass = Class.new
+    ActiveResource::Formats.const_set(:MsgpackFormat, klass)
+
+    assert_equal klass, ActiveResource::Formats[:msgpack]
+  ensure
+    ActiveResource::Formats.send(:remove_const, :MsgpackFormat)
+  end
+
+  def test_unknown_format_raises_not_found_error
+    assert_raises NameError, match: "uninitialized constant ActiveResource::Formats::MsgpackFormat" do
+      ActiveResource::Formats[:msgpack]
+    end
+  end
+
+  def test_json_format_uses_acronym_inflections
+    ActiveSupport::Inflector.inflections { |inflect| inflect.acronym "JSON" }
+
+    assert_equal ActiveResource::Formats::JsonFormat, ActiveResource::Formats[:json]
+  ensure
+    ActiveSupport::Inflector.inflections.clear :acronyms
+  end
+
+  def test_xml_format_uses_acronym_inflections
+    ActiveSupport::Inflector.inflections { |inflect| inflect.acronym "XML" }
+
+    assert_equal ActiveResource::Formats::XmlFormat, ActiveResource::Formats[:xml]
+  ensure
+    ActiveSupport::Inflector.inflections.clear :acronyms
+  end
+end