[aaronrobertshaw]

Follows up on #83122.
Core backport: wordpress-develop#14094.

Related:

• Colour: Add a PHP helper for block support classes and styles #84206
• Border: Add a PHP helper for block support classes and styles #84207
• Spacing: Add a PHP helper for block support classes and styles #84208
• Background: Add a PHP helper for block support classes and styles #84209

What?

Adds a PHP helper that turns a block's shadow into inline styles, like the JS getShadowClassesAndStyles().

wp_get_shadow_classes_and_styles( $block_attributes );
// array( 'style' => 'box-shadow:var(--wp--preset--shadow--natural);' )

The shadow block support and six blocks now use it.

Why?

Blocks that skip shadow serialization apply the shadow to an inner element, so they build the styles by hand. Six do, each with its own style engine call. A shared helper gives them one place to change.

How?

The helper only builds output. It doesn't check what a block supports. Each caller decides where the output goes.

• Shadow block support: keeps its checks, then calls the helper
• Avatar, Post Featured Image: shadow on the image
• Navigation Submenu: shadow on the dropdown, not the menu item
• Search: shadow on the same elements as the border
• Post Navigation Link: splits its style engine call around the helper, keeping the same order
• Icon: same split as Post Navigation Link
• Build: added to prefixFunctions, so the plugin calls gutenberg_get_shadow_classes_and_styles()

No output changes.

PHPStan's WordPress stubs are built from Core trunk, which won't have this helper until wordpress-develop#14094 lands. So this PR adds a temporary baseline entry for it. PHPStan will flag the entry for removal once the stubs move to a Core trunk with the helper.

Testing Instructions

1. Add an Avatar, a Post Featured Image with an overlay, and a Post Navigation Link.
2. Add a Navigation block with a submenu, a Search block and an Icon block.
3. Give each a shadow. Give Avatar, Post Featured Image and Post Navigation Link a border too.
4. Compare the front end markup with trunk. It should match.
5. Open the submenu. The shadow is on the dropdown, not on the menu item.

Use of AI Tools

Implemented and tested by a Claude Code agent from a predefined task.

[github-actions]

🤖 PR meta 🤖

🎉 Props

If you're merging code through a pull request on GitHub, copy and paste the following into the bottom of the merge commit message.

Co-authored-by: aaronrobertshaw <aaronrobertshaw@git.wordpress.org>
Co-authored-by: westonruter <westonruter@git.wordpress.org>
Co-authored-by: ramonjd <ramonopoly@git.wordpress.org>
Co-authored-by: andrewserong <andrewserong@git.wordpress.org>

To understand the WordPress project's expectations around crediting contributors, please review the Contributor Attribution page in the Core Handbook.

---

Props Bot commands

You can trigger Props Bot actions by commenting on this PR:

• @propsbot add <username> to give props to a GitHub user. Requires write access.
• @propsbot remove <username> to leave a user out of the props. Requires write access.
• @propsbot refresh to refresh this list. Adding the props-bot label works too.

Updated as activity occurs, without notifying anyone named here. Add the props-bot label to refresh.

📦 Bundle size

Size Change: 0 B

Total Size: 8.61 MB

_{1a3c0e7 Run}

⚡ Performance

Show the results

Client side metrics exclude the server response time.

front-end-block-theme

Metric	4bd13e8	trunk	% Change
timeToFirstByte	43.65 ms +15.01% -6.07%	42.55 ms +4.82% -4.94%	2.59%
largestContentfulPaint	76 ms +5.26% -10.53%	68 ms +8.82% -0%	11.76%
lcpMinusTtfb	27.7 ms +24.73% -3.25%	27.5 ms +1.64% -3.64%	0.73%
wpBeforeTemplate	22.98 ms +19.58% -5.27%	21.87 ms +7.09% -3.02%	5.08%
wpTemplate	17.1 ms +9.18% -4.09%	16.66 ms +4.68% -4.62%	2.64%
wpTotal	40.38 ms +14.61% -5.92%	39.22 ms +5.07% -5.43%	2.96%
wpMemoryUsage	7.72 MB +0% -0%	7.68 MB +0% -0%	0.43%
wpDbQueries	16 +0% -0%	16 +0% -0%	0%

front-end-classic-theme

Metric	4bd13e8	trunk	% Change
timeToFirstByte	32.4 ms +8.8% -2.62%	34.7 ms +5.33% -2.02%	-6.63%
largestContentfulPaint	72 ms +5.56% -2.78%	76 ms +5.26% -0%	-5.26%
lcpMinusTtfb	38.65 ms +4.01% -4.53%	42.5 ms +2% -2%	-9.06%
wpBeforeTemplate	19.55 ms +10.23% -2.92%	18.86 ms +5.04% -0.95%	3.66%
wpTemplate	10.21 ms +1.86% -2.35%	12.88 ms +3.49% -5.12%	-20.73%
wpTotal	29.7 ms +9.29% -1.92%	31.99 ms +5.16% -1.69%	-7.16%
wpMemoryUsage	6.30 MB +0% -0%	6.37 MB +0% -0%	-1.21%
wpDbQueries	9 +0% -0%	13 +0% -0%	-30.77%

media-processing

Metric	4bd13e8	trunk	% Change
mediaProcessingJpeg	325.95 ms +1.08% -1.47%	320.72 ms +1.16% -0.66%	1.63%
mediaProcessingAvif	4874.14 ms +0.32% -0.56%	4816.44 ms +0.49% -0.05%	1.2%
mediaProcessingJpegToAvif	3381.44 ms +0.17% -0.28%	3373.93 ms +0.17% -0.15%	0.22%

media-upload

Metric	4bd13e8	trunk	% Change
jpegUploadProcessing	1418.33 ms +1.78% -0.28%	1423.11 ms +0.49% -0.96%	-0.34%
pngUploadProcessing	212.82 ms +3.16% -1.93%	201.89 ms +6.65% -1.06%	5.41%
largeJpegUploadProcessing	1407.43 ms +0.69% -0.63%	1413.35 ms +0.35% -0.37%	-0.42%
multipleImageUploadProcessing	1489.15 ms +1.06% -0.76%	1477.59 ms +1.41% -1.22%	0.78%

post-editor

Metric	4bd13e8	trunk	% Change
serverResponse	488.88 ms +2.33% -9.95%	472.31 ms +7.6% -4.88%	3.51%
firstPaint	458.91 ms +7.86% -9.91%	346.27 ms +43.67% -6.02%	32.53%
domContentLoaded	847.66 ms +3.77% -1.3%	890.66 ms +2.79% -1.06%	-4.83%
loaded	848.86 ms +3.76% -1.29%	891.64 ms +2.78% -1.04%	-4.8%
firstContentfulPaint	495.42 ms +4.94% -2.38%	514.58 ms +3.59% -0.85%	-3.72%
firstBlock	2195.08 ms +3.23% -0.68%	2284.9 ms +1.23% -2.89%	-3.93%
type	17.39 ms +6.61% -9.32%	20.2 ms +0.74% -4.41%	-13.91%
typeWithoutInspector	17.22 ms +7.14% -7.9%	19.42 ms +1.6% -15.09%	-11.33%
typeWithTopToolbar	22.5 ms +13.6% -2.62%	26.52 ms +5.47% -7.84%	-15.16%
typeContainer	8.48 ms +16.39% -9.08%	9.53 ms +2.41% -9.02%	-11.02%
focus	126.39 ms +5.4% -4.03%	122.23 ms +5.51% -5.49%	3.4%
firstFocus	264.09 ms +0% -0%	256.52 ms +0% -0%	2.95%
selectAll	415.28 ms +1.11% -1.97%	418.75 ms +0.08% -0.04%	-0.83%
undo	30.76 ms +3.71% -6.96%	31.6 ms +8.32% -5.09%	-2.66%
listViewOpen	79.51 ms +13.63% -4.25%	79.29 ms +15.59% -2.16%	0.28%
inserterOpen	43.15 ms +17.5% -8.83%	43.21 ms +2.92% -7.85%	-0.14%
inserterHover	12.5 ms +4.32% -20.56%	12.32 ms +10.88% -15.83%	1.46%
inserterSearch	8.67 ms +5.88% -8.19%	8.52 ms +7.98% -5.99%	1.76%
loadPatterns	659.54 ms +6.04% -4.38%	663.44 ms +4% -2.42%	-0.59%
wpTotal	478.68 ms +2.22% -10.11%	462.48 ms +7.53% -5%	3.5%
wpMemoryUsage	14.76 MB +0% -0%	14.73 MB +0% -0%	0.24%
wpDbQueries	55 +0% -0%	55 +0% -0%	0%

site-editor

Metric	4bd13e8	trunk	% Change
serverResponse	255.81 ms +1.5% -8.29%	261.62 ms +1.39% -7.74%	-2.22%
firstPaint	247.8 ms +30.77% -10.48%	251.76 ms +16.06% -2.32%	-1.57%
domContentLoaded	561.01 ms +3.16% -1.45%	590.98 ms +2.93% -1.41%	-5.07%
loaded	561.68 ms +3.15% -1.45%	591.83 ms +2.92% -1.42%	-5.09%
firstContentfulPaint	330.29 ms +5.15% -1.83%	342.1 ms +4.42% -0.98%	-3.45%
firstBlock	1660.98 ms +0.57% -0.55%	1740.75 ms +1.27% -2.49%	-4.58%
type	13.34 ms +3.75% -9.22%	13.53 ms +6.13% -8.72%	-1.4%
navigate	74.61 ms +5.2% -6.46%	76.07 ms +9.46% -11.95%	-1.92%
loadPatterns	1059.65 ms +8.2% -11.58%	896.03 ms +13.79% -12.79%	18.26%
loadPages	927.79 ms +1.3% -1.18%	943.49 ms +0.84% -0.51%	-1.66%
wpTotal	249.42 ms +1.54% -8.39%	255.29 ms +1.3% -8.06%	-2.3%
wpMemoryUsage	12.78 MB +0% -0%	12.74 MB +0% -0%	0.27%
wpDbQueries	45 +0% -0%	45 +0% -0%	0%

_{1a3c0e7 Run}

🏁 Flaky tests

Some tests passed with failed attempts. The failures may not be related to this commit but are still reported for visibility. See the documentation for more information.

Undo restores the post selection when another synced entity is loaded (RTC WebSocket) in /test/e2e/specs/editor/collaboration/collaboration-undo-redo.spec.ts, passed after 1 failed attempt.

Error: expect(received).toMatchObject(expected)

- Expected  - 2
+ Received  + 2

  Object {
    "attributeKey": "content",
    "blockIndex": 0,
    "content": "abcdef",
-   "endOffset": 3,
-   "offset": 3,
+   "endOffset": 6,
+   "offset": 6,
  }

Call Log:
- Timeout 5000ms exceeded while waiting on the predicate
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/collaboration/collaboration-undo-redo.spec.ts:363:5

Undo restores the post selection when another synced entity is loaded in /test/e2e/specs/editor/collaboration/collaboration-undo-redo.spec.ts, passed after 1 failed attempt.

Error: expect(received).toMatchObject(expected)

- Expected  - 2
+ Received  + 2

  Object {
    "attributeKey": "content",
    "blockIndex": 0,
    "content": "abcdef",
-   "endOffset": 3,
-   "offset": 3,
+   "endOffset": 4,
+   "offset": 4,
  }

Call Log:
- Timeout 5000ms exceeded while waiting on the predicate
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/collaboration/collaboration-undo-redo.spec.ts:363:5

User Mention: should cancel mention selection via `Escape` keypress event in /test/e2e/specs/editor/various/autocomplete-and-mentions.spec.js, passed after 2 failed attempts.

Error: apiRequestContext.fetch: socket hang up
Call log:
  - → DELETE http://localhost:8891/wp-json/wp/v2/users/23?force=true&reassign=1
    - user-agent: Playwright/1.63.0 (x64; ubuntu 24.04) node/24.20 CI/1
    - accept: */*
    - accept-encoding: gzip,deflate,br
    - X-WP-Nonce: 33bfe1cf3b
    - cookie: wordpress_test_cookie=WP%20Cookie%20check; wordpress_logged_in_da433b7faafd8180ebeb1624ceeeab7e=admin%7C1793971969%7Chsc89YRbmzN3Z5CvYRIeph6eoB5taChYleCd7uxO6Ip%7Cfd2536eaa0601e32afae2b7c0dd5ed25ea83be86d131f043e6dc4e650d5139b4; wp-settings-time-1=1793799477; wp-settings-1=editor%3Dtinymce

    at RequestUtils.rest (/home/runner/work/gutenberg/gutenberg/packages/e2e-test-utils-playwright/src/request-utils/rest.ts:111:39)
    at RequestUtils.deleteUser (/home/runner/work/gutenberg/gutenberg/packages/e2e-test-utils-playwright/src/request-utils/users.ts:91:30)
    at map (/home/runner/work/gutenberg/gutenberg/packages/e2e-test-utils-playwright/src/request-utils/users.ts:116:51)
    at RequestUtils.deleteAllUsers (/home/runner/work/gutenberg/gutenberg/packages/e2e-test-utils-playwright/src/request-utils/users.ts:116:5)
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/autocomplete-and-mentions.spec.js:73:3

inserts a block should show a blue line indicator in /test/e2e/specs/editor/various/inserting-blocks.spec.js, passed after 1 failed attempt.

Error: expect(locator).toBeVisible() failed

Locator: locator('data-testid=block-list-insertion-point-indicator')
Expected: visible
Timeout: 5000ms
Error: element(s) not found

Call log:
  - Expect "toBeVisible" locator('data-testid=block-list-insertion-point-indicator') with timeout 5000ms
  - waiting for locator('data-testid=block-list-insertion-point-indicator')

    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/inserting-blocks.spec.js:674:50

should place the caret at the click position when clicking a block that is not selected in /test/e2e/specs/editor/various/writing-flow.spec.js, passed after 1 failed attempt.

Error: expect(received).toMatchObject(expected)

- Expected  - 1
+ Received  + 1

@@ -1,9 +1,9 @@
  Array [
    Object {
      "attributes": Object {
-       "content": "First!",
+       "content": "First",
      },
      "name": "core/paragraph",
    },
    Object {
      "attributes": Object {

Call Log:
- Timeout 5000ms exceeded while waiting on the predicate
    at /home/runner/work/gutenberg/gutenberg/test/e2e/specs/editor/various/writing-flow.spec.js:952:41

_{1a3c0e7 Run}

[ramonjd]

Thanks for keeping these alive.

Tested manually on the (now) 4 blocks. All manifestations of the search block. Added borders and shadows to all (except submenu, which only takes borders).

Editor	Frontend

[aaronrobertshaw]

Thanks for the reviews and testing 👍

I've pushed a few final tweaks:

• Icon and Post Navigation Link are back to trunk's shadow handling, with their new tests kept.
• The helper now returns early if the attributes aren't an array, the same as the colour, border and background helpers.
• Moved to 7.3, both the @since tag and the backport changelog entry.
• Rebased on trunk.

PHPStan landed on trunk this week and doesn't know about the new helpers yet, since it isn't in Core until WordPress/wordpress-develop#14094. So I've added a temporary baseline entry for it.