Avoid mutating global STDOUT & STDERR (#1837)

[MitchLewis930]

PR_051

[Copilot]

Pull request overview

This PR modifies the Puma::Events class to avoid mutating global STDOUT and STDERR objects by duplicating them instead of using the originals directly.

Changes:

• Updated Puma::Events#initialize to duplicate stdout/stderr arguments instead of using them directly
• Modified tests to verify that duplicated streams are used and that sync settings are respected
• Added test setup to ensure test infrastructure can access the duplicated logger outputs

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
lib/puma/events.rb	Changed to duplicate stdout/stderr arguments to avoid mutating globals
test/test_events.rb	Updated assertions to compare inspected strings and added test for sync behavior
test/test_tcp_logger.rb	Added instance variable assignment to support test infrastructure

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[Copilot]

This test mutates the global STDOUT object by setting sync to false, which could affect other tests. The test should restore the original sync value in an ensure block to prevent side effects on other tests.

Suggested change

	def test_stdio_respects_sync
	STDOUT.sync = false
	events = Puma::Events.stdio
	assert !STDOUT.sync
	assert events.stdout.sync
	def test_stdio_respects_sync
	original_sync = STDOUT.sync
	STDOUT.sync = false
	events = Puma::Events.stdio
	assert !STDOUT.sync
	assert events.stdout.sync
	ensure
	STDOUT.sync = original_sync

[Copilot]

Corrected spelling of 'loggers' to 'logger's'.

Suggested change

	logger.instance_variable_set(:@stdout, $stdout) # ensure capture_process_io has access to the loggers output
	logger.instance_variable_set(:@stdout, $stdout) # ensure capture_process_io has access to the logger's output