Merge pull request rails#55465 from joshuay03/fix-55460

[Fix rails#55460] Make `ActiveSupport::Logger` `#freeze`-friendly

Author: rafaelfranca

activesupport/CHANGELOG.md

@@ -1,3 +1,7 @@
+*   Make `ActiveSupport::Logger` `#freeze`-friendly.
+
+    *Joshua Young*
+
 *   Make `ActiveSupport::Gzip.compress` deterministic based on input.
 
     `ActiveSupport::Gzip.compress` used to include a timestamp in the output,

activesupport/lib/active_support/logger_thread_safe_level.rb

@@ -7,6 +7,11 @@ module ActiveSupport
   module LoggerThreadSafeLevel # :nodoc:
     extend ActiveSupport::Concern
 
+    def initialize(...)
+      super
+      @local_level_key = :"logger_thread_safe_level_#{object_id}"
+    end
+
     def local_level
       IsolatedExecutionState[local_level_key]
     end
@@ -40,8 +45,6 @@ def log_at(level)
     end
 
     private
-      def local_level_key
-        @local_level_key ||= :"logger_thread_safe_level_#{object_id}"
-      end
+      attr_reader :local_level_key
   end
 end

activesupport/test/logger_test.rb

@@ -382,6 +382,37 @@ def test_logger_level_thread_safety
     ActiveSupport::IsolatedExecutionState.isolation_level = previous_isolation_level
   end
 
+  def test_logger_freeze
+    logger = @logger.clone
+    logger.freeze
+
+    assert_nothing_raised do
+      assert_equal Logger::DEBUG, logger.level
+
+      logger.debug "I am frozen 1"
+      assert_includes @output.string, "I am frozen 1"
+
+      logger.debug { "I am frozen 2" }
+      assert_includes @output.string, "I am frozen 2"
+
+      logger.add Logger::INFO, "I am frozen 3"
+      assert_includes @output.string, "I am frozen 3"
+
+      logger.silence do
+        logger.debug "I am frozen 4"
+      end
+      assert_not_includes @output.string, "I am frozen 4"
+    end
+
+    assert_raises FrozenError do
+      logger.level = Logger::INFO
+    end
+
+    assert_raises FrozenError do
+      logger.formatter = Logger::Formatter.new
+    end
+  end
+
   def test_temporarily_logging_at_a_noisier_level
     @logger.level = Logger::INFO