Gallery block: Add full align gallery support and unit tests

[mukeshpanchal27]

Summary

Part of #2449

Treat child Image blocks of a full aligned Gallery as aligned, alongside the existing wide alignment handling. A full aligned gallery only spans the viewport when it has a single column, so multi-column galleries fall back to the default sizes.

Add unit tests covering full aligned galleries with equal and unequal column counts, the 'is_parent_aligned' render block context, and the Image block context declarations.

Use of AI Tools

N/A

[Copilot]

Pull request overview

This PR extends the Auto Sizes plugin’s Gallery handling so that child core/image blocks inside a full-aligned Gallery inherit alignment behavior (similar to existing wide-alignment support), and it adds unit tests to cover the new behavior and context plumbing.

Changes:

• Treat core/gallery blocks with align: "full" as “parent aligned” so child core/image blocks can inherit alignment when they don’t explicitly set their own.
• Add logic to fall back to default sizes for inherited full alignment when the gallery image is not effectively full-width (based on container_relative_width).
• Add/extend unit tests for full-aligned galleries, is_parent_aligned render-block context, and core/image context usage declarations.

Reviewed changes

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

File	Description
plugins/auto-sizes/includes/improve-calculate-sizes.php	Adds full-aligned Gallery inheritance for child Images and a fallback to default sizes when full alignment shouldn’t apply.
plugins/auto-sizes/tests/test-improve-calculate-sizes.php	Adds unit tests for full-aligned gallery scenarios and validates new/required render-block context behavior.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 70.50%. Comparing base (a4f79e2) to head (714535c).

Additional details and impacted files

@@                  Coverage Diff                   @@
##           fix/2449-equal-column    #2587   +/-   ##
======================================================
  Coverage                  70.50%   70.50%           
======================================================
  Files                         91       91           
  Lines                       7882     7884    +2     
======================================================
+ Hits                        5557     5559    +2     
  Misses                      2325     2325           

Flag	Coverage Δ
multisite	70.50% <100.00%> (+<0.01%)	⬆️
single	35.87% <100.00%> (+0.01%)	⬆️

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (2)

plugins/auto-sizes/tests/test-improve-calculate-sizes.php:2177

• In the full-aligned, multi-column gallery case with an incomplete last row (remainder=1), the expected sizes for the last image is sizes="100vw", which contradicts the intent stated just above (that multi-column full galleries fall back to default sizes, including incomplete rows) and the PR description.

If multi-column full galleries should always use default sizes, the last image here should also use the default sizes string instead of 100vw.

				3,
				2,
				'sizes="(max-width: 1024px) 100vw, 1024px" ',
				'sizes="100vw" ',
			),

plugins/auto-sizes/includes/improve-calculate-sizes.php:141

• The new early-return for inherited full alignment only checks container_relative_width !== 1.0. However, for a multi-column gallery’s incomplete last row where remainder=1, auto_sizes_filter_render_block_context() sets container_relative_width to 1.0 for that last image (it uses 1.0 / $remainder). This means the last image can still be treated as full and end up with sizes="100vw", even though the PR description says multi-column full-aligned galleries should fall back to default sizes.

If the intended behavior is “any gallery with column_count > 1 uses default sizes for all images”, consider passing the gallery column count (or a boolean like is_parent_multi_column) through block context to the child Image blocks and using that instead of relying solely on container_relative_width.

			$is_parent_gallery_aligned = (bool) ( $block->context['is_parent_aligned'] ?? false );
			if ( $is_parent_gallery_aligned && '' === $alignment ) {
				$alignment = $max_alignment;

				/*
				 * A full alignment normally spans the whole viewport, but inside a narrower
				 * container (e.g. a column) the gallery is constrained to that container instead.
				 * The resulting width cannot be expressed reliably here, so keep the default sizes.
				 */
				if ( 1.0 !== (float) $container_relative_width && 'full' === $alignment ) {
					return $sizes;

[github-actions]

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Co-authored-by: mukeshpanchal27 <mukesh27@git.wordpress.org>

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