fix: preserve locale data in unnamed groups with localizeStatus

[JarrodMFlesch]

Summary

• Fixes data loss for fields inside unnamed groups when publishing with localizeStatus: true
• Also fixes same issue for row, collapsible, and unnamed tab fields
• Root cause: mergeLocalizedData() was incorrectly processing pass-through/layout-only fields

Technical Details

The bug occurred because pass-through fields (unnamed groups, rows, collapsibles, unnamed tabs) used Object.assign(result, merged) after recursive calls, which would overwrite already-processed fields with stale data.

The fix:

1. Added collectFlattenedFieldNames() helper to extract field names belonging to a layout field
2. Pass original docWithLocales to recursive calls (not result)
3. After recursion, copy only the specific fields belonging to that layout field

Test plan

• Added failing unit test for unnamed groups (Data of Fields within Unnamed Group Is Lost On Localized Publish #15642 reproduction)
• Added regression test for row fields
• Added regression test for unnamed tabs
• All 16 mergeLocalizedData unit tests pass

Fixes #15642

[Copilot]

Pull request overview

Fixes a localized publishing data-loss bug in mergeLocalizedData() when traversing pass-through / layout-only fields (unnamed groups, rows, collapsibles, unnamed tabs), which could previously overwrite already-merged locale data.

Changes:

• Add collectFlattenedFieldNames() and use it to selectively copy only the affected keys after recursing through pass-through fields.
• Update recursion for pass-through/layout-only fields to use the original docWithLocales (and avoid Object.assign-style overwrites).
• Add unit/regression tests covering unnamed groups, row fields, and unnamed tabs for locale preservation.

Reviewed changes

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

File	Description
packages/payload/src/utilities/mergeLocalizedData.ts	Prevents stale overwrite when merging through pass-through fields by selectively copying only relevant keys.
packages/payload/src/utilities/mergeLocalizedData.spec.ts	Adds regression tests reproducing #15642 and covering related pass-through layouts.

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[github-actions]

📦 esbuild Bundle Analysis for payload

This analysis was generated by esbuild-bundle-analyzer. 🤖

Meta File	Out File	Size (raw)	Note
packages/next/meta_index.json	esbuild/index.js	950.34 KB	✅ No change
packages/payload/meta_index.json	esbuild/index.js	1.32 MB	⚠️ +186 B (+0.0%)
packages/payload/meta_shared.json	esbuild/exports/shared.js	168.53 KB	✅ No change
packages/richtext-lexical/meta_client.json	esbuild/exports/client_optimized/index.js	281.79 KB	✅ No change
packages/ui/meta_client.json	esbuild/exports/client_optimized/index.js	1.17 MB	✅ No change
packages/ui/meta_shared.json	esbuild/exports/shared_optimized/index.js	16.32 KB	✅ No change

Largest paths

These visualization shows top 20 largest paths in the bundle.

Meta file: packages/next/meta_index.json, Out file: esbuild/index.js

Path	Size
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dist/views/Version	${{\color{Goldenrod}{ █▎ }}}$ 5.4%, 51.27 KB
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dist/views/Document	${{\color{Goldenrod}{ ▍ }}}$ 1.7%, 16.18 KB
dist/views/List	${{\color{Goldenrod}{ ▎ }}}$ 1.2%, 11.28 KB
dist/views/Root	${{\color{Goldenrod}{ ▎ }}}$ 1.0%, 9.03 KB
dist/views/Versions	${{\color{Goldenrod}{ ▏ }}}$ 0.7%, 6.16 KB
dist/views/API	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 6.08 KB
dist/elements/Nav	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 5.96 KB
dist/views/Account	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 5.46 KB
dist/elements/DocumentHeader	${{\color{Goldenrod}{ ▏ }}}$ 0.5%, 4.81 KB
dist/views/Login	${{\color{Goldenrod}{ ▏ }}}$ 0.5%, 4.40 KB
dist/views/ForgotPassword	${{\color{Goldenrod}{ }}}$ 0.3%, 3.09 KB
dist/layouts/Root	${{\color{Goldenrod}{ }}}$ 0.3%, 2.91 KB
dist/views/CreateFirstUser	${{\color{Goldenrod}{ }}}$ 0.3%, 2.81 KB
dist/templates/Default	${{\color{Goldenrod}{ }}}$ 0.3%, 2.63 KB
dist/views/BrowseByFolder	${{\color{Goldenrod}{ }}}$ 0.3%, 2.61 KB
dist/views/CollectionFolders	${{\color{Goldenrod}{ }}}$ 0.3%, 2.44 KB
dist/views/ResetPassword	${{\color{Goldenrod}{ }}}$ 0.3%, 2.40 KB
dist/views/Logout	${{\color{Goldenrod}{ }}}$ 0.2%, 1.94 KB
(other)	${{\color{Goldenrod}{ ████▍ }}}$ 17.6%, 166.53 KB

Meta file: packages/payload/meta_index.json, Out file: esbuild/index.js

Path	Size
../../node_modules	${{\color{Goldenrod}{ ████████████████▉ }}}$ 67.7%, 887.23 KB
dist/fields/hooks	${{\color{Goldenrod}{ ▊ }}}$ 3.3%, 43.59 KB
dist/collections/operations	${{\color{Goldenrod}{ ▊ }}}$ 3.0%, 39.75 KB
dist/versions/migrations	${{\color{Goldenrod}{ ▎ }}}$ 1.4%, 18.50 KB
dist/auth/operations	${{\color{Goldenrod}{ ▎ }}}$ 1.2%, 15.74 KB
dist/globals/operations	${{\color{Goldenrod}{ ▎ }}}$ 1.0%, 13.17 KB
dist/fields/config	${{\color{Goldenrod}{ ▎ }}}$ 1.0%, 12.84 KB
dist/queues/operations	${{\color{Goldenrod}{ ▎ }}}$ 1.0%, 12.80 KB
dist/utilities/configToJSONSchema.js	${{\color{Goldenrod}{ ▏ }}}$ 0.9%, 12.07 KB
dist/fields/validations.js	${{\color{Goldenrod}{ ▏ }}}$ 0.8%, 10.54 KB
dist/bin/generateImportMap	${{\color{Goldenrod}{ ▏ }}}$ 0.7%, 8.77 KB
dist/collections/config	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 8.35 KB
dist/index.js	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 7.69 KB
dist/uploads/fetchAPI-multipart	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 7.67 KB
dist/database/migrations	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 7.54 KB
dist/config/orderable	${{\color{Goldenrod}{ ▏ }}}$ 0.5%, 6.83 KB
dist/collections/endpoints	${{\color{Goldenrod}{ ▏ }}}$ 0.5%, 6.22 KB
dist/config/sanitize.js	${{\color{Goldenrod}{ }}}$ 0.4%, 5.58 KB
dist/auth/strategies	${{\color{Goldenrod}{ }}}$ 0.4%, 5.50 KB
dist/auth/endpoints	${{\color{Goldenrod}{ }}}$ 0.4%, 5.42 KB
(other)	${{\color{Goldenrod}{ ████████ }}}$ 32.3%, 422.42 KB

Meta file: packages/payload/meta_shared.json, Out file: esbuild/exports/shared.js

Path	Size
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dist/fields/validations.js	${{\color{Goldenrod}{ █▌ }}}$ 6.4%, 10.54 KB
dist/config/orderable	${{\color{Goldenrod}{ ▍ }}}$ 1.9%, 3.13 KB
dist/fields/baseFields	${{\color{Goldenrod}{ ▍ }}}$ 1.7%, 2.79 KB
dist/utilities/deepCopyObject.js	${{\color{Goldenrod}{ ▍ }}}$ 1.5%, 2.54 KB
dist/auth/cookies.js	${{\color{Goldenrod}{ ▏ }}}$ 0.9%, 1.55 KB
dist/utilities/flattenTopLevelFields.js	${{\color{Goldenrod}{ ▏ }}}$ 0.9%, 1.42 KB
dist/fields/config	${{\color{Goldenrod}{ ▏ }}}$ 0.8%, 1.28 KB
dist/utilities/getVersionsConfig.js	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 1.04 KB
dist/utilities/flattenAllFields.js	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 943 B
dist/folders/utils	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 916 B
dist/utilities/unflatten.js	${{\color{Goldenrod}{ ▏ }}}$ 0.5%, 779 B
dist/utilities/sanitizeUserDataForEmail.js	${{\color{Goldenrod}{ }}}$ 0.4%, 713 B
dist/utilities/getFieldPermissions.js	${{\color{Goldenrod}{ }}}$ 0.4%, 651 B
dist/collections/config	${{\color{Goldenrod}{ }}}$ 0.3%, 570 B
dist/bin/generateImportMap	${{\color{Goldenrod}{ }}}$ 0.3%, 561 B
dist/auth/sessions.js	${{\color{Goldenrod}{ }}}$ 0.3%, 525 B
dist/fields/getFieldPaths.js	${{\color{Goldenrod}{ }}}$ 0.3%, 485 B
dist/utilities/getSafeRedirect.js	${{\color{Goldenrod}{ }}}$ 0.3%, 423 B
dist/utilities/deepMerge.js	${{\color{Goldenrod}{ }}}$ 0.3%, 413 B
(other)	${{\color{Goldenrod}{ █████▋ }}}$ 22.9%, 37.77 KB

Meta file: packages/richtext-lexical/meta_client.json, Out file: esbuild/exports/client_optimized/index.js

Path	Size
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dist/lexical/plugins	${{\color{Goldenrod}{ ██▉ }}}$ 11.5%, 32.00 KB
dist/lexical/ui	${{\color{Goldenrod}{ ██▏ }}}$ 8.7%, 24.36 KB
dist/features/experimental_table	${{\color{Goldenrod}{ ██▏ }}}$ 8.5%, 23.70 KB
dist/packages/@lexical	${{\color{Goldenrod}{ █▋ }}}$ 6.8%, 18.99 KB
dist/features/link	${{\color{Goldenrod}{ █▋ }}}$ 6.5%, 18.23 KB
dist/features/toolbars	${{\color{Goldenrod}{ █▌ }}}$ 6.4%, 17.75 KB
dist/features/upload	${{\color{Goldenrod}{ █▏ }}}$ 4.9%, 13.77 KB
dist/features/textState	${{\color{Goldenrod}{ █ }}}$ 4.0%, 11.08 KB
dist/features/relationship	${{\color{Goldenrod}{ ▊ }}}$ 3.2%, 9.03 KB
dist/lexical/utils	${{\color{Goldenrod}{ ▊ }}}$ 3.0%, 8.49 KB
dist/features/debug	${{\color{Goldenrod}{ ▋ }}}$ 2.7%, 7.39 KB
dist/utilities/fieldsDrawer	${{\color{Goldenrod}{ ▋ }}}$ 2.6%, 7.15 KB
dist/features/converters	${{\color{Goldenrod}{ ▋ }}}$ 2.5%, 7.05 KB
dist/lexical/config	${{\color{Goldenrod}{ ▍ }}}$ 1.8%, 5.08 KB
dist/features/lists	${{\color{Goldenrod}{ ▍ }}}$ 1.8%, 5.00 KB
dist/features/format	${{\color{Goldenrod}{ ▎ }}}$ 1.2%, 3.46 KB
dist/lexical/LexicalEditor.js	${{\color{Goldenrod}{ ▎ }}}$ 1.1%, 3.17 KB
dist/lexical/theme	${{\color{Goldenrod}{ ▏ }}}$ 0.9%, 2.62 KB
dist/features/indent	${{\color{Goldenrod}{ ▏ }}}$ 0.9%, 2.50 KB
(other)	${{\color{Goldenrod}{ █████████████████████▊ }}}$ 87.4%, 243.38 KB

Meta file: packages/ui/meta_client.json, Out file: esbuild/exports/client_optimized/index.js

Path	Size
../../node_modules	${{\color{Goldenrod}{ ████████████▍ }}}$ 49.7%, 578.96 KB
dist/elements/FolderView	${{\color{Goldenrod}{ ▋ }}}$ 2.5%, 29.29 KB
dist/elements/BulkUpload	${{\color{Goldenrod}{ ▌ }}}$ 2.4%, 27.63 KB
dist/elements/WhereBuilder	${{\color{Goldenrod}{ ▍ }}}$ 1.5%, 17.09 KB
dist/views/Edit	${{\color{Goldenrod}{ ▎ }}}$ 1.4%, 16.74 KB
dist/fields/Relationship	${{\color{Goldenrod}{ ▎ }}}$ 1.4%, 15.78 KB
dist/elements/Table	${{\color{Goldenrod}{ ▎ }}}$ 1.4%, 15.77 KB
dist/forms/Form	${{\color{Goldenrod}{ ▎ }}}$ 1.3%, 15.31 KB
dist/fields/Upload	${{\color{Goldenrod}{ ▎ }}}$ 1.2%, 14.24 KB
dist/fields/Blocks	${{\color{Goldenrod}{ ▎ }}}$ 1.2%, 13.69 KB
dist/elements/QueryPresets	${{\color{Goldenrod}{ ▏ }}}$ 0.9%, 10.32 KB
dist/elements/PublishButton	${{\color{Goldenrod}{ ▏ }}}$ 0.8%, 9.06 KB
dist/providers/Folders	${{\color{Goldenrod}{ ▏ }}}$ 0.7%, 8.47 KB
dist/elements/LivePreview	${{\color{Goldenrod}{ ▏ }}}$ 0.7%, 8.38 KB
dist/elements/ListHeader	${{\color{Goldenrod}{ ▏ }}}$ 0.7%, 7.90 KB
dist/elements/HTMLDiff	${{\color{Goldenrod}{ ▏ }}}$ 0.7%, 7.81 KB
dist/fields/Array	${{\color{Goldenrod}{ ▏ }}}$ 0.7%, 7.73 KB
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dist/elements/ReactSelect	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 7.34 KB
dist/views/List	${{\color{Goldenrod}{ ▏ }}}$ 0.6%, 7.02 KB
(other)	${{\color{Goldenrod}{ ████████████▌ }}}$ 50.3%, 586.67 KB

Meta file: packages/ui/meta_shared.json, Out file: esbuild/exports/shared_optimized/index.js

Path	Size
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dist/graphics/Icon	${{\color{Goldenrod}{ ██▍ }}}$ 9.8%, 1.52 KB
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dist/utilities/api.js	${{\color{Goldenrod}{ █▏ }}}$ 4.8%, 756 B
dist/elements/Translation	${{\color{Goldenrod}{ ▊ }}}$ 3.2%, 493 B
dist/utilities/handleTakeOver.js	${{\color{Goldenrod}{ ▋ }}}$ 2.8%, 440 B
dist/utilities/traverseForLocalizedFields.js	${{\color{Goldenrod}{ ▋ }}}$ 2.6%, 399 B
dist/elements/withMergedProps	${{\color{Goldenrod}{ ▌ }}}$ 2.2%, 339 B
dist/utilities/getVisibleEntities.js	${{\color{Goldenrod}{ ▌ }}}$ 2.1%, 329 B
dist/utilities/getNavGroups.js	${{\color{Goldenrod}{ ▍ }}}$ 1.9%, 301 B
dist/elements/WithServerSideProps	${{\color{Goldenrod}{ ▍ }}}$ 1.5%, 232 B
dist/utilities/handleGoBack.js	${{\color{Goldenrod}{ ▎ }}}$ 1.2%, 180 B
dist/fields/mergeFieldStyles.js	${{\color{Goldenrod}{ ▎ }}}$ 1.0%, 159 B
dist/utilities/handleBackToDashboard.js	${{\color{Goldenrod}{ ▎ }}}$ 1.0%, 152 B
dist/forms/Form	${{\color{Goldenrod}{ ▏ }}}$ 0.9%, 147 B
dist/utilities/abortAndIgnore.js	${{\color{Goldenrod}{ ▏ }}}$ 0.9%, 146 B
(other)	${{\color{Goldenrod}{ ████████████████████ }}}$ 80.0%, 12.51 KB

Details

Next to the size is how much the size has increased or decreased compared with the base branch of this PR.

• ‼️: Size increased by 20% or more. Special attention should be given to this.
• ⚠️: Size increased in acceptable range (lower than 20%).
• ✅: No change or even downsized.
• 🗑️: The out file is deleted: not found in base branch.
• 🆕: The out file is newly found: will be added to base branch.