Components: Add `exhaustive-deps` eslint rule

[chad1008]

Note: This PR shouldn't be merged until after the list of updates below is completed to ensure everything is ready to pass!

What?

Activate the exhaustive-deps rule to trigger warnings for missing deps in dependency arrays for useEffect, useLayoutEffect, useMemo, useCallback, or useImperativeHandle

Why?

Missing dependencies can lead to unexpected results like stale state values. This rule helps us guard against that.

How?

Below is a list of the components/files that currently throw exhuastive-deps warnings. I'll be going through as many as possible (help from other contributors is of course welcome!) to analyze and udpate as needed. Once all components are passing linting,this PR can be merged, activating the rule for the entire Components package.

Testing Instructions

1. Apply this PR
2. From your local gutenberg directory, run npx eslint --rule 'react-hooks/exhaustive-deps: warn' packages/components/src

Components and files to be updated:

• [x] alignment-matrix-control @chad1008 #41167
• [x] autocomplete @chad1008 #41382
• [x] border-box-control @ciampo #41254
• [x] border-control @chad1008 #41259
• [x] color-palette @chad1008 #41253
• [x] color-picker @stokesman #41294
• [x] combobox-control @chad1008 #41417
• [x] custom-gradient-bar @chad1008 #41463
• [x] date-time @chad1008 #41470
• [x] draggable @chad1008 #41499
• [x] dropdown @chad1008 #41505
• [x] flex/flex @chad1008 #41507
• [x] focal-point-picker @chad1008 #41520
• [x] font-size-picker @chad1008 #41600
• [x] input-control @chad1008 #41601
• [x] mobile/* @chad1008 #44207
• [x] modal @chad1008 #41610
• [x] navigation @chad1008 #41612
• [x] navigation/item @chad1008 #41639
• [x] navigation/menu @chad1008 #44090
• [x] navigator/navigator-button @flootr #42051
• [x] navigator/navigator-screen @chad1008 #43876
• [x] notice @chad1008 #44157
• [ ] palette-edit @flootr #43911
• [x] popover @ciampo #43320
• [x] range-control @chad1008 #44271
• [ ] resizable-box/resize-tooltip @chad1008 #44370
• [ ] sandbox @chad1008 #44378
• [ ] search-control @chad1008 #44381
• [ ] slot-fill
• [ ] snackbar
• [ ] tab-panel
• [ ] tools-panel/tools-panel-item
• [ ] tools-panel/tools-panel
• [ ] tooltip
• [x] unit-control @ciampo #44161
• [ ] ui/context/context-system-provider.js
• [ ] utils/hooks/use-update-effect.js

cc @mirka @ciampo

[github-actions[bot]]

Size Change: 0 B

Total Size: 1.29 MB

ℹ️ View Unchanged

Filename	Size
build/a11y/index.min.js	982 B
build/annotations/index.min.js	2.76 kB
build/api-fetch/index.min.js	2.26 kB
build/autop/index.min.js	2.14 kB
build/blob/index.min.js	475 B
build/block-directory/index.min.js	7.09 kB
build/block-directory/style-rtl.css	990 B
build/block-directory/style.css	991 B
build/block-editor/default-editor-styles-rtl.css	378 B
build/block-editor/default-editor-styles.css	378 B
build/block-editor/index.min.js	174 kB
build/block-editor/style-rtl.css	15.9 kB
build/block-editor/style.css	15.9 kB
build/block-library/blocks/archives/editor-rtl.css	61 B
build/block-library/blocks/archives/editor.css	60 B
build/block-library/blocks/archives/style-rtl.css	90 B
build/block-library/blocks/archives/style.css	90 B
build/block-library/blocks/audio/editor-rtl.css	150 B
build/block-library/blocks/audio/editor.css	150 B
build/block-library/blocks/audio/style-rtl.css	122 B
build/block-library/blocks/audio/style.css	122 B
build/block-library/blocks/audio/theme-rtl.css	126 B
build/block-library/blocks/audio/theme.css	126 B
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build/block-library/blocks/avatar/editor.css	116 B
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build/block-library/blocks/avatar/style.css	84 B
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build/block-library/blocks/button/editor.css	482 B
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build/block-library/blocks/button/style.css	532 B
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build/block-library/blocks/buttons/editor.css	337 B
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build/block-library/blocks/buttons/style.css	332 B
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build/block-library/blocks/freeform/editor.css	2.44 kB
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build/block-library/blocks/gallery/editor.css	950 B
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build/block-library/blocks/navigation/view-modal.min.js	2.78 kB
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build/block-library/blocks/page-list/style.css	175 B
build/block-library/blocks/paragraph/editor-rtl.css	174 B
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build/block-library/blocks/post-template/style.css	282 B
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build/block-library/blocks/pullquote/editor-rtl.css	135 B
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build/block-library/blocks/query-pagination-numbers/editor-rtl.css	122 B
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build/block-library/blocks/search/editor-rtl.css	165 B
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build/block-library/blocks/search/theme.css	114 B
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build/block-library/blocks/separator/theme.css	194 B
build/block-library/blocks/shortcode/editor-rtl.css	464 B
build/block-library/blocks/shortcode/editor.css	464 B
build/block-library/blocks/site-logo/editor-rtl.css	490 B
build/block-library/blocks/site-logo/editor.css	490 B
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build/block-library/blocks/social-link/editor.css	184 B
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build/block-library/blocks/text-columns/style.css	166 B
build/block-library/blocks/verse/style-rtl.css	87 B
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build/block-library/blocks/video/editor-rtl.css	691 B
build/block-library/blocks/video/editor.css	694 B
build/block-library/blocks/video/style-rtl.css	174 B
build/block-library/blocks/video/style.css	174 B
build/block-library/blocks/video/theme-rtl.css	126 B
build/block-library/blocks/video/theme.css	126 B
build/block-library/classic-rtl.css	162 B
build/block-library/classic.css	162 B
build/block-library/common-rtl.css	1.02 kB
build/block-library/common.css	1.02 kB
build/block-library/editor-elements-rtl.css	75 B
build/block-library/editor-elements.css	75 B
build/block-library/editor-rtl.css	11.3 kB
build/block-library/editor.css	11.3 kB
build/block-library/elements-rtl.css	54 B
build/block-library/elements.css	54 B
build/block-library/index.min.js	193 kB
build/block-library/reset-rtl.css	478 B
build/block-library/reset.css	478 B
build/block-library/style-rtl.css	12.4 kB
build/block-library/style.css	12.4 kB
build/block-library/theme-rtl.css	704 B
build/block-library/theme.css	708 B
build/block-serialization-default-parser/index.min.js	1.12 kB
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build/blocks/index.min.js	49.9 kB
build/components/index.min.js	203 kB
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build/data-controls/index.min.js	653 B
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build/date/index.min.js	32.1 kB
build/deprecated/index.min.js	507 B
build/dom-ready/index.min.js	324 B
build/dom/index.min.js	4.7 kB
build/edit-navigation/index.min.js	16.1 kB
build/edit-navigation/style-rtl.css	3.99 kB
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build/edit-post/classic-rtl.css	546 B
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build/edit-widgets/style-rtl.css	4.34 kB
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build/editor/style-rtl.css	3.6 kB
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build/element/index.min.js	4.68 kB
build/escape-html/index.min.js	537 B
build/experiments/index.min.js	868 B
build/format-library/index.min.js	6.95 kB
build/format-library/style-rtl.css	571 B
build/format-library/style.css	571 B
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build/keycodes/index.min.js	1.83 kB
build/list-reusable-blocks/index.min.js	2.13 kB
build/list-reusable-blocks/style-rtl.css	835 B
build/list-reusable-blocks/style.css	835 B
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build/notices/index.min.js	963 B
build/nux/index.min.js	2.06 kB
build/nux/style-rtl.css	732 B
build/nux/style.css	728 B
build/plugins/index.min.js	1.94 kB
build/preferences-persistence/index.min.js	2.22 kB
build/preferences/index.min.js	1.33 kB
build/primitives/index.min.js	944 B
build/priority-queue/index.min.js	1.58 kB
build/react-i18n/index.min.js	696 B
build/react-refresh-entry/index.min.js	8.44 kB
build/react-refresh-runtime/index.min.js	7.31 kB
build/redux-routine/index.min.js	2.74 kB
build/reusable-blocks/index.min.js	2.21 kB
build/reusable-blocks/style-rtl.css	256 B
build/reusable-blocks/style.css	256 B
build/rich-text/index.min.js	10.7 kB
build/server-side-render/index.min.js	1.77 kB
build/shortcode/index.min.js	1.53 kB
build/style-engine/index.min.js	1.48 kB
build/token-list/index.min.js	644 B
build/url/index.min.js	3.61 kB
build/vendors/inert-polyfill.min.js	2.48 kB
build/vendors/react-dom.min.js	38.5 kB
build/vendors/react.min.js	4.34 kB
build/viewport/index.min.js	1.08 kB
build/warning/index.min.js	268 B
build/widgets/index.min.js	7.21 kB
build/widgets/style-rtl.css	1.18 kB
build/widgets/style.css	1.19 kB
build/wordcount/index.min.js	1.06 kB

_{compressed-size-action}

[gziolo]

If possible it would be great to maintain all ESLint rules from a central location using overrides:

https://github.com/WordPress/gutenberg/blob/59f42b3aed9c40165515629613d8e5920bb74977/.eslintrc.js#L179

Otherwise it’s harder to reason how rules resolve because the information is chunked in a few places.

It’d be important to reference the previous attempt to introduce this rule in https://github.com/WordPress/gutenberg/pull/24914. There was a long discussion so I guess it isn’t that simple to work with this rule 😅

[ciampo]

@gziolo 's advice makes sense to me — we could do something like

diff --git a/.eslintrc.js b/.eslintrc.js
index 22c354394d..e70d083496 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -224,6 +224,13 @@ module.exports = {
 				],
 			},
 		},
+		{
+			files: [ 'packages/components/src/**/*.js' ],
+			excludedFiles: [ ...developmentFiles ],
+			rules: {
+				'react-hooks/exhaustive-deps': 'warn',
+			},
+		},
 		{
 			files: [ 'packages/jest*/**/*.js', '**/test/**/*.js' ],
 			excludedFiles: [ 'test/e2e/**/*.js' ],

This way, we could also widen this rule to cover more packages in the future.

[chad1008]

Awesome, I was going to ask if using overrides this way made sense, thank you!

[chad1008]

The rule has been moved to the plugin's central eslintrc file as suggested ✅

[chad1008]

Cleared to to-do list. Checked for new/missed warnings and there are about a dozen spread across a handful of components. Shouldn't take long 🤞

[ciampo]

All currently known exhaustive-deps violations in the components package should be fixed 🎉 Let's rebase and see if we're able to enable this rule for the package!

One thing: currently in this PR the rule will generate warnings, should we consider erroring instead?

---

Update: I rebased and changed the lint rule from warn to error — of course we can always revert to warn if we feel like.

It looks like ToolsPanelItem recently introduced one more violation of the rule (#45715)

[chad1008]

Thank you @flootr and @ciampo for knocking out those last few PRs. The list (including the recent additions) is now complete!

Running npx eslint --rule 'react-hooks/exhaustive-deps: warn' packages/components/src/ locally, I no longer see any exhaustive-deps warnings 🎉 so we should be in pretty good shape. Marking this as ready for review.

[ciampo]

I guess the last thing to decided is whether we should warn or error for this rule — @tyxla do you have any opinions / suggestions on this one?

[chad1008]

Thanks @ciampo

[tyxla]

error makes sense to me; we already witnessed that not following this rule can potentially cause damage, so I'd also go with error for now. We can always adjust if we reconsider.