feat(nuxt): support lazy hydration macros #31192

Mini-ghost · 2025-03-03T11:08:55Z

🔗 Linked issue

📚 Description

This PR introduces a few macros to provide an explicit import solution for lazy hydration.

resolves #31663

TODO

Macro plugin (LazyHydrationMacroTransformPlugin)
Type support
Documentation
Tests

Visibility Strategy

Visibility strategy enables deferring the hydration of a component until the element(s) become visible in the viewport.

<script setup lang="ts">
const LazyHydrationMyComponent = defineLazyHydrationComponent(
  'visible',
  () => import('./components/MyComponent.vue')
)
</script>
<template>
  <div>
    <!-- 
      Hydration will be triggered when
      the element(s) is 100px away from entering the viewport.
    -->
    <LazyHydrationMyComponent :hydrate-on-visible="{ rootMargin: '100px' }" />
  </div>
</template>

Idle Strategy

Idle strategy enables deferring the hydration of a component until the browser is idle, ensuring that critical rendering tasks are prioritized first.

<script setup lang="ts">
const LazyHydrationMyComponent = defineLazyHydrationComponent(
  'idle',
  () => import('./components/MyComponent.vue')
)
</script>
<template>
  <div>
    <!-- Hydration will be triggered when the browser is idle or after 2000ms. -->
    <LazyHydrationMyComponent :hydrate-on-idle="2000" />
  </div>
</template>

Interaction Strategy

Interaction strategy enables delaying the hydration of a component until a user interacts with it (e.g., click, mouseover).

<script setup lang="ts">
const LazyHydrationMyComponent = defineLazyHydrationComponent(
  'interaction',
  () => import('./components/MyComponent.vue')
)
</script>
<template>
  <div>
    <!--
      Hydration will be triggered when
      the element(s) is hovered over by the pointer.
    -->
    <LazyHydrationMyComponent hydrate-on-interaction="mouseover" />
  </div>
</template>

Media Query Strategy

Media query strategy enables deferring the hydration of a component until a specified media query matches.

<script setup lang="ts">
const LazyHydrationMyComponent = defineLazyHydrationComponent(
  'mediaQuery',
  () => import('./components/MyComponent.vue')
)
</script>
<template>
  <div>
    <!--
      Hydration will be triggered when
      the window width is greater than or equal to 768px.
    -->
    <LazyHydrationMyComponent hydrate-on-media-query="(min-width: 768px)" />
  </div>
</template>

If Strategy

If strategy enables delaying the hydration of a component until a boolean condition is met.

<script setup lang="ts">
const LazyHydrationMyComponent = defineLazyHydrationComponent(
  'if',
  () => import('./components/MyComponent.vue')
)
const isReady = ref(false)
function myFunction() {
  // Trigger custom hydration strategy...
  isReady.value = true
}
</script>
<template>
  <div>
    <!-- Hydration is triggered when isReady becomes true. -->
    <LazyHydrationMyComponent :hydrate-when="isReady" />
  </div>
</template>

Time Strategy

Time strategy enables delaying the hydration of a component until a specified time (in milliseconds) has passed.

<script setup lang="ts">
const LazyHydrationMyComponent = defineLazyHydrationComponent(
  'time', 
  () => import('./components/MyComponent.vue')
)
</script>
<template>
  <div>
    <!-- Hydration is triggered after 1000ms. -->
    <LazyHydrationMyComponent :hydrate-after="1000" />
  </div>
</template>

Never Hydrate

Never strategy prevents the component from being hydrated by Vue. This means that the component remains static and does not require Vue's hydration process.

<script setup lang="ts">
const LazyHydrationMyComponent = defineLazyHydrationComponent(
  'never',
  () => import('./components/MyComponent.vue')
)
</script>
<template>
  <div>
    <!-- This component will never be hydrated by Vue. -->
    <LazyHydrationMyComponent />
  </div>
</template>

If there's anything I may have overlooked or if you have any suggestions, please feel free to let me know. I truly appreciate your feedback.

bolt-new-by-stackblitz · 2025-03-03T11:08:58Z

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commit: 140ca41

codspeed-hq · 2025-03-03T11:30:18Z

CodSpeed Performance Report

Merging #31192 will not alter performance

_{Comparing Mini-ghost:feat/support-lazy-hydration-micro (140ca41) with main (d680c3f)}

Summary

✅ 10 untouched benchmarks

coderabbitai · 2025-03-06T15:00:01Z

Walkthrough

This update introduces a macro-based system for defining lazy hydration strategies in Nuxt applications. A new macro, defineLazyHydrationComponent, is implemented with support for various hydration triggers such as visibility, idle, interaction, media query, conditional, timed, and never hydrate. The system is enabled via a build plugin (LazyHydrationMacroTransformPlugin) and a corresponding import preset. Documentation is added to describe usage and strategies, while tests and example pages are updated or created to demonstrate and verify the macro's behaviour. Component prop defaults are adjusted for flexibility, and the transformation logic is enhanced to be scope-aware.

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coderabbitai

Actionable comments posted: 7

🧹 Nitpick comments (10)

docs/3.api/3.utils/define-lazy-media-query-component.md (1)
50-50: Add parentheses around the media query value for consistency.

The media query value doesn't include parentheses in this example, but the prop name and earlier example suggest they should be included.
-    <LazyMediaQueryMyComponent hydrate-on-media-query="min-width: 768px" />
+    <LazyMediaQueryMyComponent hydrate-on-media-query="(min-width: 768px)" />
docs/3.api/3.utils/define-lazy-never-component.md (1)
34-34: Consider adding missing documentation sections.

Unlike the other lazy hydration component documentation, this file doesn't include an Emits section. For consistency, consider adding an empty emits section or clarify if this component doesn't emit events.

If the component doesn't emit any events, consider adding:
## Emits

This component doesn't emit any events since it's never hydrated.
docs/3.api/3.utils/define-lazy-idle-component.md (1)
46-46: Clarify the default timeout duration.

The documentation mentions a "default timeout duration" when passing true, but doesn't specify what that duration is.

Consider updating to include the actual default timeout value:
-You can pass a number to specify a timeout duration. If hydration has not been triggered within this duration, it will occur automatically. Alternatively, pass `true` to use the default timeout duration. The number must be a positive value; otherwise, it will be ignored.
+You can pass a number to specify a timeout duration in milliseconds. If hydration has not been triggered within this duration, it will occur automatically. Alternatively, pass `true` to use the default timeout duration (typically 5000ms, but may vary). The number must be a positive value; otherwise, it will be ignored.
docs/3.api/3.utils/define-lazy-interaction-component.md (1)
15-17: Fix formatting issue with tip block.

There appears to be a formatting issue with the tip block delimiter where it's being detected as "loose punctuation".

Add a new line before the ::tip directive to ensure proper Markdown rendering:
- When using `v-if="false"` on a lazy component, you might not need delayed hydration. You can just use a normal lazy component.
- ::tip
+ When using `v-if="false"` on a lazy component, you might not need delayed hydration. You can just use a normal lazy component.
+ 
+ ::tip
🧰 Tools

🪛 LanguageTool

[uncategorized] ~16-~16: Loose punctuation mark.
Context: ...until the component is actually needed. :: ## Usage ```vue <script setup lang="...

(UNLIKELY_OPENING_PUNCTUATION)
test/fixtures/basic/pages/lazy-import-components/delayed-hydration/macro/model-event.vue (1)
13-16: Consider enhancing the logging function with more detailed information.

The current logging function is simple and functional but could be more informative for debugging purposes.

Consider enhancing the log function to include more details, like a timestamp:
-function log () {
-  console.log('Component hydrated')
+function log () {
+  console.log(`Component hydrated at ${new Date().toISOString()}`)
docs/3.api/3.utils/define-lazy-if-component.md (1)
15-17: Fix formatting issue with tip block.

There appears to be a formatting issue with the tip block delimiter where it's being detected as "loose punctuation".

Add a new line before the ::tip directive to ensure proper Markdown rendering:
- When using `v-if="false"` on a lazy component, you might not need delayed hydration. You can just use a normal lazy component.
- ::tip
+ When using `v-if="false"` on a lazy component, you might not need delayed hydration. You can just use a normal lazy component.
+ 
+ ::tip
🧰 Tools

🪛 LanguageTool

[uncategorized] ~16-~16: Loose punctuation mark.
Context: ...ng resources are only used when needed. :: ## Usage ```vue <script setup lang="...

(UNLIKELY_OPENING_PUNCTUATION)
packages/nuxt/test/lazy-hydration-macro-transform.test.ts (2)

80-81: Consider consolidating repeated checks.

Each test suite repeats the same transformation check and similar assertions. Extracting these repeated snippet checks into a shared helper function could remove duplication and make the tests more maintainable.

134-185: Expand testing for corner cases.

The transform function currently tests positive scenarios of matching macros. Adding tests for corner cases (e.g., partial macro matches, malformed imports, or multiple macros in a single line) can help ensure robustness.

Would you like assistance creating additional test cases that validate failure modes or handle advanced edge cases?

packages/nuxt/src/components/plugins/lazy-hydration-macro-transform.ts (2)

18-19: Watch out for potential edge cases.

Relying on these regex patterns for matching may capture unexpected code fragments if a file inadvertently contains similar syntax. Consider adding stricter checks or fallback warnings to notify developers of potential partial matches.

53-62: Add a diagnostic log or warning.

When a variable name or component name is missing, the code is simply removed. Logging a small warning would help developers catch unintentional misconfigurations or typos.

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docs/3.api/3.utils/define-lazy-after-component.md (1 hunks)
docs/3.api/3.utils/define-lazy-idle-component.md (1 hunks)
docs/3.api/3.utils/define-lazy-if-component.md (1 hunks)
docs/3.api/3.utils/define-lazy-interaction-component.md (1 hunks)
docs/3.api/3.utils/define-lazy-media-query-component.md (1 hunks)
docs/3.api/3.utils/define-lazy-never-component.md (1 hunks)
docs/3.api/3.utils/define-lazy-visible-component.md (1 hunks)
packages/nuxt/src/components/module.ts (2 hunks)
packages/nuxt/src/components/plugins/lazy-hydration-macro-transform.ts (1 hunks)
packages/nuxt/src/components/runtime/lazy-hydrated-component.ts (3 hunks)
packages/nuxt/test/lazy-hydration-macro-transform.test.ts (1 hunks)
test/basic.test.ts (1 hunks)
test/fixtures/basic/pages/lazy-import-components/delayed-hydration/index.vue (1 hunks)
test/fixtures/basic/pages/lazy-import-components/delayed-hydration/macro/index.vue (1 hunks)
test/fixtures/basic/pages/lazy-import-components/delayed-hydration/macro/model-event.vue (1 hunks)
test/fixtures/basic/pages/lazy-import-components/delayed-hydration/macro/time.vue (1 hunks)
test/fixtures/basic/pages/lazy-import-components/index.vue (0 hunks)

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test/fixtures/basic/pages/lazy-import-components/index.vue

🧰 Additional context used

🪛 LanguageTool

docs/3.api/3.utils/define-lazy-interaction-component.md

[uncategorized] ~14-~14: Loose punctuation mark.
Context: ... can just use a normal lazy component. ::tip You can use `defineLazyInteractionC...