Respect Warning settings before calling custom handler

[spawnia]

Check whether the warning is enabled before invoking the custom warning handler, matching the behavior for the default trigger_error handler.

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.50.

Benchmark suite	Current: e920ef9	Previous: 203d11e	Ratio
DeferredBench::benchManyNestedDeferreds	21.952 ms	12.472 ms	1.76

This comment was automatically generated by workflow using github-action-benchmark.

[Copilot]

Pull request overview

This PR updates the library’s warning emission logic so custom warning handlers respect Warning::enable() / Warning::suppress() settings, matching the default trigger_error behavior.

Changes:

• Gate custom warning handler invocation behind the same enableWarnings bitmask check used for trigger_error.
• Refactor warning emission to centralize “should warn” logic and streamline warnOnce() behavior.
• Update the lazy schema executor test to assert warning handling behavior (currently needs fixes to actually execute).

Reviewed changes

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

File	Description
tests/Executor/ExecutorLazySchemaTest.php	Adds assertions for warning interception via a custom warning handler during lazy schema execution.
src/Error/Warning.php	Ensures warnings are only emitted/handled when enabled; refactors warnOnce()/warn() and introduces shouldWarn().
CHANGELOG.md	Documents the behavior change for custom warning handlers respecting suppression.

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[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (3)

tests/Executor/ExecutorLazySchemaTest.php:140

• markTestIncomplete() aborts the test, so the new assertions and $warnings verification below it are unreachable. It also prevents resetting the global warning handler, which can leak into other tests.

        Warning::enable(Warning::WARNING_FULL_SCHEMA_SCAN);
        $result = Executor::execute($schema, Parser::parse($query));
        self::markTestIncomplete('No longer works with PHPUnit 10, reintroduce with https://github.com/webonyx/graphql-php/pull/1393');
        self::assertEquals($expected, $result);

src/Error/Warning.php:62

• The suppress() docblock says it has no effect when a custom warning handler is set, but this PR changes behavior to respect suppression/enablement before invoking the custom handler. The doc comment should be updated to match.

    public static function suppress($suppress = true): void
    {
        if ($suppress === true) {
            self::$enableWarnings = self::NONE;

src/Error/Warning.php:90

• The enable() docblock says it has no effect when a custom warning handler is set, but this PR makes enablement affect custom handlers too. Update the doc comment so it matches the new behavior.

    public static function enable($enable = true): void
    {
        if ($enable === true) {
            self::$enableWarnings = self::ALL;
        } elseif ($enable === false) {
            self::$enableWarnings = self::NONE;