Script Loader: Preserve duplicate query variables in enqueued script and style URLs.

[westonruter]

Previously, using add_query_arg() to append versions or handle-specific query arguments would strip any existing duplicate query variables in the source URL (common in Google Fonts URLs).

This change refactors WP_Styles::_css_href() and WP_Scripts::do_item() to manually append these parameters to the URL string. This ensures all original query variables are preserved exactly as provided. It also improves fragment handling by ensuring query parameters are inserted before any '#' anchor while maintaining the anchor's presence.

Regression tests are added to verify preservation of duplicate query variables and fragments using WP_HTML_Tag_Processor for precise attribute verification.

The URL encoding changes in tests/phpunit/tests/dependencies/scripts.php are reversions of what had previously been done in c4d8047.

Follow-up to r61397.

Props @nichita231.
See #64372.

This issue would have been impacted quite a few themes and plugins:

• https://wpdirectory.net/search/01KJXS8RRHSDRJV7H0KT6VFZR0
• https://wpdirectory.net/search/01KJXSAX6A4YB48GMA58JTDK0Z

Trac ticket: https://core.trac.wordpress.org/ticket/64372

Use of AI Tools

I iterated with Gemini CLI on adding tests to reproduce the issue, and then to iterated back and forth on changes. Then I had Gemini draft a commit message and commit.

Prompts

1. Initial instruction regarding add_query_arg() eliminating repeated query vars in WP_Styles and WP_Scripts, with a request for a better solution and unit tests.

2. Don't add a new test file. Just add to the existing files which were previously modified in c4d8047. Add the new tests in the appropriate spot, probably right after the tests added in that commit to those two files

3. You can supply --group=64372 to just one call to npm run test:php

4. As opposed to using assertStringContainsString, it would be better to assert on the entire URL being the same. Let's provide 'https://example.com/' URLs for each script and style and add assetions to assertSame for the entire string

5. Let's actually compare URLs. Extract the href/src from the tag via the WP_HTML_Tag_Processor and then compare the attribute value with the expected URL

6. Let's also add assertTrue() checks to the next_tag calls

7. ok, now you provided an abbreviated "$frag" variable. Let's avoid this abbreviation. use $fragment

8. None of the tests provide any URLs with fragments

9. Wouldn't it make sense to skip setting $fragment to an empy string if strstr() returns false, and then to only append $fragment onto $src if it is a string?

10. for the tests, the phpdoc descriptions should all use 3rd singular person verbs to start (e.g. "Tests")

11. I see there are failures now when I run pm run test:php -- --group=scripts

12. I think you should rather change the URLs back to what they had been beforec c4d8047. YOu can see that I had changed the URLs to deal with the encoding change

13. That doesn't look relevant. I mean literally to undo the fixture changes I had made in c4d8047.

14. Your sed commands keep failing.

15. ok, now based on all of the changes we've made together, and the changes which are staged in git, write a commit message and commit

16. This code doesn't seem ideal:

    $added_args = isset( $this->args[ $handle ] ) ? (string) $this->args[ $handle ] : ''

    It should rather be:

    $added_args = (string) ( $this->args[ $handle ] ?? '' );

17. Add a new commit

18. There is redundancy in this code:

    	$added_ver = '';
    	if ( empty( $obj->ver ) && null !== $obj->ver && is_string( $this->default_version ) ) {
    		$added_ver = 'ver=' . rawurlencode( $this->default_version );
    	} elseif ( is_scalar( $obj->ver ) ) {
    		$added_ver = 'ver=' . rawurlencode( (string) $obj->ver );
    	}

    I think it should set $added_ver to $this->default_version or (string) $obj->ver and then below if $added_ver is not '', then append 'ver=' . rawurlencode( $added_ver )

19. You can simplify the commit message without the additional references or component name. Refer to the previous commit as an exmaple

20. This looks strange: ( '' !== $ver_to_add || $added_args). Why compare with empty string for one but not the other. Can't they both just be truthy checks since they are both guaranteed to be strings?

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This Pull Request is for code review only. Please keep all other discussion in the Trac ticket. Do not merge this Pull Request. See GitHub Pull Requests for Code Review in the Core Handbook for more details.

[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

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Props westonruter, jonsurrell.

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[github-actions]

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[Copilot]

Pull request overview

This PR updates WordPress’s script/style URL building to avoid add_query_arg() re-parsing query strings (which drops duplicate query variables), preserving the original query string (including duplicates) and ensuring new parameters are inserted before any #fragment.

Changes:

• Refactors WP_Styles::_css_href() and WP_Scripts::do_item() to append ver and handle args directly onto the URL string (preserving duplicate query vars).
• Improves fragment handling by ensuring appended query parameters are added before #anchor while retaining the fragment.
• Adds regression tests asserting preservation of duplicate query vars and fragments via WP_HTML_Tag_Processor, plus updates expected markup fixtures affected by the encoding behavior change.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
src/wp-includes/class-wp-styles.php	Builds style href without add_query_arg() to preserve duplicate query vars and handle fragments correctly.
src/wp-includes/class-wp-scripts.php	Builds script src without add_query_arg() to preserve duplicate query vars and handle fragments correctly.
tests/phpunit/tests/dependencies/styles.php	Adds regression tests validating duplicate query var + fragment preservation for enqueued styles.
tests/phpunit/tests/dependencies/scripts.php	Updates fixture expectations impacted by URL encoding behavior and adds regression tests for scripts.

Comments suppressed due to low confidence (2)

src/wp-includes/class-wp-styles.php:420

• $added_args is cast to string, but the subsequent truthy checks (if ( $ver_to_add || $added_args ) / if ( $added_args )) will treat the valid query string value '0' as false and skip appending it. This is a behavior change vs the previous parse_str()/add_query_arg() path, which would still include a ?0 handle arg.

Use explicit empty-string checks (e.g. '' !== $added_args) so ?0 is preserved, while still skipping the default empty string.

		$added_args = (string) ( $this->args[ $handle ] ?? '' );

		if ( $ver_to_add || $added_args ) {
			$fragment = strstr( $src, '#' );

src/wp-includes/class-wp-scripts.php:430

• $added_args is a string, but the truthy checks (if ( $ver_to_add || $added_args ) / if ( $added_args )) will treat '0' as false and skip appending it. With a handle like foo?0, the 0 arg would now be dropped, whereas the prior parse_str()/add_query_arg() flow would preserve it.

Consider using explicit empty-string checks (e.g. '' !== $added_args) so ?0 is preserved.

		$added_args = (string) ( $this->args[ $handle ] ?? '' );

		if ( $ver_to_add || $added_args ) {
			$fragment = strstr( $src, '#' );

---

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[westonruter]

Fix tested successfully: #10608 (comment)

[sirreal]

Very interesting issue. The fix seems appropriate.

[github-actions]

A commit was made that fixes the Trac ticket referenced in the description of this pull request.

SVN changeset: 61927
GitHub commit: b8b74d5

This PR will be closed, but please confirm the accuracy of this and reopen if there is more work to be done.