feat(core)!: add as-needed prefetch strategy

[Mister-Hope]

No description provided.

[Mister-Hope]

@meteorlxy This is completed, but we should expected the following things to be preloaded as well:

• pages appears in navbars
• pages appears in the same sidebar group
• pages that is prev/next

But these are theme concept, and I am not comming up with any idea how to solve this gracefully.

Any ideas for probably a new hook for themes?

[coveralls]

Coverage Report for CI Build 30081445920

Coverage increased (+0.8%) to 73.948%

Details

• Coverage increased (+0.8%) from the base build.
• Patch coverage: 1 of 1 lines across 1 file are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	1087
Covered Lines:	800
Line Coverage:	73.6%
Relevant Branches:	552
Covered Branches:	412
Branch Coverage:	74.64%
Branches in Coverage %:	Yes
Coverage Strength:	48.34 hits per line

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💛 - Coveralls

[meteorlxy]

Maybe extract this snippet to bundlerutils?

[Mister-Hope]

How? The data structures are different accross bundlers, and rely on bundler types.

[meteorlxy]

L33-L45 is identical and duplicate across 3(4) files

[meteorlxy]

extracted to bundlerutils

[Copilot]

Pull request overview

This PR changes the default prefetch strategy to an “as-needed” mode that only emits prefetch hints for chunks belonging to pages linked from the current page, enabled via a new per-page chunk-file mapping built during bundler output generation.

Changes:

• Change shouldPrefetch default from true to 'as-needed' and extend the option type accordingly.
• Add bundlerutils helpers (createPageChunkFilesMap, resolveLinkRoutePath, resolveLinkedPageChunkFiles) plus unit tests to support linked-page chunk discovery.
• Extend webpack/vite build pipelines to compute and pass a PageChunkFilesMap into prefetch rendering; add E2E coverage for resource-hint behavior.

Reviewed changes

Copilot reviewed 27 out of 28 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
pnpm-lock.yaml	Updates workspace lock to reflect new workspace dependency usage.
packages/core/tests/app/resolveAppOptions.spec.ts	Updates expectation for new shouldPrefetch default.
packages/core/src/types/app/options.ts	Extends shouldPrefetch type and updates default value.
packages/core/src/app/resolveAppOptions.ts	Sets new default shouldPrefetch = 'as-needed'.
packages/core/src/app/prepare/prepareRoutes.ts	Exports resolvePageRedirects for reuse in mapping logic.
packages/bundlerutils/package.json	Adds @vuepress/markdown dependency for MarkdownLink typing.
packages/bundlerutils/src/build/index.ts	Re-exports new mapping/link-resolution utilities and types.
packages/bundlerutils/src/build/types.ts	Introduces PageChunkFilesMap type.
packages/bundlerutils/src/build/resolveLinkRoutePath.ts	Normalizes markdown links into route paths for map lookups.
packages/bundlerutils/src/build/resolveLinkedPageChunkFiles.ts	Computes linked pages’ chunk files for “as-needed” prefetch.
packages/bundlerutils/src/build/createPageChunkFilesMap.ts	Builds route/redirect → chunk-files map using resolvePageRedirects.
packages/bundlerutils/tests/build/resolveLinkRoutePath.spec.ts	Unit tests for link → route normalization.
packages/bundlerutils/tests/build/resolveLinkedPageChunkFiles.spec.ts	Unit tests for linked-page chunk resolution and deduping.
packages/bundlerutils/tests/build/createPageChunkFilesMap.spec.ts	Unit tests for mapping final and inferred/redirect route paths to chunks.
packages/bundler-webpack/src/build/types.ts	Extends client manifest to include chunk-name → output-files mapping.
packages/bundler-webpack/src/build/createClientPlugin.ts	Produces clientManifest.chunks mapping from webpack stats chunks.
packages/bundler-webpack/src/build/renderPagePrefetchLinks.ts	Implements 'as-needed' prefetch selection using linked-page chunks.
packages/bundler-webpack/src/build/renderPage.ts	Passes page and pageChunkFilesMap into prefetch rendering.
packages/bundler-webpack/src/build/build.ts	Builds pageChunkFilesMap from manifest chunk mapping and passes through.
packages/bundler-vite/src/build/renderPagePrefetchLinks.ts	Implements 'as-needed' prefetch selection for rolldown dynamic imports.
packages/bundler-vite/src/build/renderPage.ts	Passes page and pageChunkFilesMap into prefetch rendering.
packages/bundler-vite/src/build/build.ts	Builds pageChunkFilesMap using resolvePageChunkFiles and passes through.
e2e/tests/resource-hints.spec.ts	Adds E2E assertions that only linked pages’ resources are prefetched (not preloaded), including virtual pages.
e2e/docs/.vuepress/config.ts	Creates a virtual source page during initialization for E2E coverage.
e2e/docs/resource-hints/source.md	Adds a source page linking to linked/permalink pages for E2E.
e2e/docs/resource-hints/linked.md	Adds linked page fixture.
e2e/docs/resource-hints/linked-permalink.md	Adds linked page fixture with permalink frontmatter.
e2e/docs/resource-hints/unlinked.md	Adds unlinked page fixture used to compute differences in E2E.

Files not reviewed (1)

• pnpm-lock.yaml: Generated file

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