Boost: add URL-pattern exclusions to Defer Non-Essential JavaScript

[kraftbj]

Fixes #36417

Proposed changes

• Adds an exclusion list to the Defer Non-Essential JavaScript module so specific pages can be excluded by URL pattern without disabling the feature site-wide.
• New render_blocking_js_excludes data-sync entry (array of strings, default empty), persisted via the same reusable Minify_Excludes_State_Entry used by minify_js_excludes (trims/dedupes on save). At template_redirect, the request path is checked against the patterns; on a match the module leaves the page completely untouched — output filtering is never attached and the do_shortcode_tag ignore-attribute filter is removed, so an excluded page is byte-identical to defer-disabled output. All other pages stay optimized.
• Pattern semantics mirror the Page Cache bypass patterns users already know: path-only comparison (query strings ignored), (.*)/* wildcards, optional leading/trailing slashes, case-insensitive, full URLs accepted by stripping the home URL; everything else is treated literally (preg_quoted, so user input can't break the regex). The Page Cache helper itself wasn't cleanly reusable (split across the pre-WordPress Request class and its data-sync entry), hence a self-contained matcher with the same documented behavior.
• Implements Changes_Output_After_Activation so cached pages are invalidated when the list changes.
• New collapsible "Exclude URL patterns" panel under the Defer JS module card, mirroring the existing minify-excludes MetaComponent (useDataSync + zod, notices, Tracks events). Its help text also documents the per-script data-jetpack-boost="ignore" attribute — closing the documentation gap from Boost: Include a tooltip on how to ignore JS files from defer #35461.
• Adds 22 pattern-matching unit cases plus behavioral tests for the bail-out and normal paths.

Note for reviewers: this touches the same module as #49545 (Defer JS document.write fix); whichever merges second will need a trivial rebase.

Related product discussion/links

• Part of the Boost exclusion-UX workstream (audit follow-up); siblings: Boost: keep position-dependent inline scripts (document.write) in place when Defer JS is enabled #49545, Boost: fully remove boost-cache directory on uninstall and make cleanup resilient on very large caches #49546, Boost: stop stripping SVG markup from Critical CSS while keeping style-tag breakout protection #49547, Boost: continue Critical CSS generation when a single provider fails unexpectedly #49554, Boost: let admins test extra Concatenate JS/CSS excludes per-request via GET parameters #49555.

Does this pull request change what data or activity we track or use?

Adds two UI interaction Tracks events consistent with existing minify-excludes panel events: defer_js_excludes_panel_toggle and defer_js_exceptions_save_clicked. No new user/site data is collected.

Testing instructions

1. Enable Defer Non-Essential JavaScript. Load a front-end page logged out and view source: non-essential <script> tags are moved to just before </body>.
2. In Boost settings, expand Exclude URL patterns under the Defer JS card, enter the page's path (e.g. checkout or gallery/(.*)), Save — a "Changes saved" notice appears.
3. Reload the excluded page (logged out, cache cleared): markup should be identical to defer-disabled output (scripts in original positions, no data-jetpack-boost attributes). Comparing with curl against defer-off output should show byte-identical HTML.
4. Load a different page: scripts are still deferred there.
5. Reload the Boost admin page: saved patterns persist in the input and the "Except: …" summary.
6. Optional: add data-jetpack-boost="ignore" to one script on a non-excluded page and confirm only that script stays in place.
7. Unit tests: cd projects/plugins/boost && vendor/bin/phpunit-select-config phpunit.#.xml.dist --bootstrap tests/bootstrap.php --testsuite unit --filter Render_Blocking_JS_Test (19 tests, 45 assertions; full unit suite 117 tests passing).

https://claude.ai/code/session_01PgpTrtTCH4hpz6Krh3ssho

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Generated by Claude Code

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Code Coverage Summary

Coverage changed in 2 files.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/boost/app/modules/optimizations/render-blocking-js/class-render-blocking-js.php	81/139 (58.27%)	48.05%	-21 💚
projects/plugins/boost/app/lib/class-output-filter.php	11/13 (84.62%)	84.62%	-22 💚

1 file is newly checked for coverage.

File	Coverage
projects/plugins/boost/app/assets/src/js/features/render-blocking-js/render-blocking-js-meta.tsx	0/30 (0.00%) 💔

Full summary · PHP report · JS report

_{Coverage check overridden by Coverage tests to be added later Use to ignore the Code coverage requirement check when tests will be added in a follow-up PR .}

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[Copilot]

Pull request overview

Adds URL-pattern exclusions to Boost’s Defer Non-Essential JavaScript optimization so admins can exclude specific pages without disabling Defer JS site-wide, including UI to manage patterns and PHPUnit coverage for matching + bailout behavior.

Changes:

• Introduces a new data-sync entry (render_blocking_js_excludes) and URL-pattern matcher to skip all Defer JS output filtering on matching requests.
• Adds an “Exclude URL patterns” collapsible panel to the Defer JS module card (with Tracks events and help text including the per-script ignore attribute).
• Expands PHPUnit coverage with URL-matching semantics cases and tests for the excluded vs non-excluded output-filtering paths; adds a test bootstrap polyfill for str_contains() in non-WP unit runs.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
projects/plugins/boost/app/modules/optimizations/render-blocking-js/class-render-blocking-js.php	Registers a new data-sync option and bails out of output filtering when the current request matches an excluded URL pattern.
projects/plugins/boost/app/assets/src/js/pages/index/index.tsx	Mounts the new Defer JS exclusions meta panel under the Defer JS module card.
projects/plugins/boost/app/assets/src/js/features/render-blocking-js/render-blocking-js-meta.tsx	Adds the UI for editing/saving excluded URL patterns and documents data-jetpack-boost="ignore".
projects/plugins/boost/app/assets/src/js/features/render-blocking-js/render-blocking-js-meta.module.scss	Styles the new exclusions meta panel.
projects/plugins/boost/tests/php/modules/optimizations/render-blocking-js/Render_Blocking_JS_Test.php	Adds URL-matching semantics tests and verifies excluded requests don’t attach output filtering / ignore-attribute behavior.
projects/plugins/boost/tests/bootstrap.php	Adds a guarded str_contains() polyfill for unit tests running without WordPress on PHP < 8.0.
projects/plugins/boost/changelog/add-defer-js-url-excludes	Changelog entry documenting the new Defer JS URL exclusions feature.