Add prototype for custom test reporter for minitest

Gemfile.lock

@@ -3,6 +3,7 @@ PATH
   specs:
     ruby-lsp (0.23.12)
       language_server-protocol (~> 3.17.0)
+      minitest-reporters
       prism (>= 1.2, < 2.0)
       rbs (>= 3, < 4)
       sorbet-runtime (>= 0.5.10782)

lib/minitest/reporters/ruby_lsp_reporter.rb

@@ -0,0 +1,116 @@
+# typed: strict
+# frozen_string_literal: true
+
+require "sorbet-runtime"
+require "ruby_lsp/test_reporter"
+
+# NOTE: minitest-reporters mentioned an API change between minitest 5.10 and 5.11, so we should verify:
+# https://github.com/minitest-reporters/minitest-reporters/blob/265ff4b40d5827e84d7e902b808fbee860b61221/lib/minitest/reporters/base_reporter.rb#L82-L91
+
+# TODO: the other reporters call print_info for formatting and backtrace filtering. Look into if we should also do that.
+
+# unless defined?(Minitest::Reporters)
+#   puts "Minitest::Reporters not defined. Please add `gem 'minitest-reporters'` to your Gemfile."
+#   exit(1)
+# end
+
+require "minitest/reporters"
+
+module Minitest
+  module Reporters
+    # TODO: consider if minitest-reporrters should be a dependency of ruby-lsp
+    class RubyLspReporter < ::Minitest::Reporters::BaseReporter
+      extend T::Sig
+
+      sig { void }
+      def initialize
+        @reporting = T.let(RubyLsp::TestReporter.new, RubyLsp::TestReporter)
+        super
+      end
+
+      sig { params(test: Minitest::Test).void }
+      def before_test(test)
+        @reporting.before_test(
+          id: id_from_test(test),
+          file: file_for_test(test),
+        )
+        super
+      end
+
+      sig { params(test: Minitest::Test).void }
+      def after_test(test)
+        @reporting.after_test(
+          id: id_from_test(test),
+          file: file_for_test(test),
+        )
+        super
+      end
+
+      sig { params(test: Minitest::Result).void }
+      def record(test)
+        super
+
+        if test.passed?
+          record_pass(test)
+        elsif test.skipped?
+          record_skip(test)
+        elsif test.failure
+          record_fail(test)
+        end
+      end
+
+      sig { params(result: Minitest::Result).void }
+      def record_pass(result)
+        info = {
+          id: id_from_result(result),
+          file: result.source_location[0],
+        }
+        @reporting.record_pass(**info)
+      end
+
+      sig { params(result: Minitest::Result).void }
+      def record_skip(result)
+        info = {
+          id: id_from_result(result),
+          message: result.failure.message,
+          file: result.source_location[0],
+        }
+        @reporting.record_skip(**info)
+      end
+
+      sig { params(result: Minitest::Result).void }
+      def record_fail(result)
+        info = {
+          id: id_from_result(result),
+          type: result.failure.class.name,
+          message: result.failure.message,
+          file: result.source_location[0],
+        }
+        @reporting.record_fail(**info)
+      end
+
+      private
+
+      sig { params(test: Minitest::Test).returns(String) }
+      def id_from_test(test)
+        [test.class.name, test.name].join("#")
+      end
+
+      sig { params(result: Minitest::Result).returns(String) }
+      def id_from_result(result)
+        [result.klass, result.name].join("#")
+      end
+
+      sig { params(test: Minitest::Test).returns(String) }
+      def file_for_test(test)
+        location = Kernel.const_source_location(test.class_name)
+        return "" unless location # TODO: when might this be nil?
+
+        file, _line = location
+        return "" if file.start_with?("(eval at ") # test is dynamically defined (TODO: better way to check?)
+
+        file
+      end
+    end
+  end
+end

lib/ruby-lsp.rb

@@ -1,6 +1,13 @@
 # typed: true
 # frozen_string_literal: true
 
+require "minitest/reporters/ruby_lsp_reporter"
+Minitest::Reporters.use!(Minitest::Reporters::RubyLspReporter.new)
+
 module RubyLsp
   VERSION = File.read(File.expand_path("../VERSION", __dir__)).strip
 end
+
+# # Temporary for verification
+# if ENV["RUBY_LSP"]
+# end

lib/ruby_lsp/test_reporter.rb

@@ -0,0 +1,86 @@
+# typed: strict
+# frozen_string_literal: true
+
+require "json"
+
+module RubyLsp
+  class TestReporter
+    extend T::Sig
+
+    sig { params(io: IO).void }
+    def initialize(io: $stdout)
+      @io = io
+    end
+
+    sig { params(id: String, file: String).void }
+    def before_test(id:, file:)
+      result = {
+        event: "before_test",
+        id: id,
+        file: file,
+      }
+      puts result
+    end
+
+    sig { params(id: String, file: String).void }
+    def after_test(id:, file:)
+      result = {
+        event: "after_test",
+        id: id,
+        file: file,
+      }
+      puts result
+    end
+
+    sig { params(id: String, file: String).void }
+    def record_pass(id:, file:)
+      result = {
+        event: "pass",
+        id: id,
+        file: file,
+      }
+      puts result
+    end
+
+    sig do
+      params(
+        id: String,
+        type: T.untyped, # TODO: what type should this be?
+        message: String,
+        file: String,
+      ).void
+    end
+    def record_fail(id:, type:, message:, file:)
+      result = {
+        event: "fail",
+        type: type,
+        message: message,
+        id: id,
+        file: file,
+      }
+      puts result
+    end
+
+    sig { params(id: String, message: T.nilable(String), file: String).void }
+    def record_skip(id:, message:, file:)
+      result = {
+        event: "skip",
+        message: message,
+        id: id,
+        file: file,
+      }
+      puts result
+    end
+
+    sig { params(result: T::Hash[Symbol, T.untyped]).void }
+    def puts(result)
+      io.puts result.to_json
+      io.flush
+    end
+
+    private
+
+    sig { returns(IO) }
+    attr_reader :io
+  end
+end

ruby-lsp.gemspec

@@ -20,6 +20,7 @@ Gem::Specification.new do |s|
 
   # Dependencies must be kept in sync with the checks in the extension side on workspace.ts
   s.add_dependency("language_server-protocol", "~> 3.17.0")
+  s.add_dependency("minitest-reporters") # version?
   s.add_dependency("prism", ">= 1.2", "< 2.0")
   s.add_dependency("rbs", ">= 3", "< 4")
   s.add_dependency("sorbet-runtime", ">= 0.5.10782")