fix(esm-library): avoid duplicate __webpack_require__ export

[JSerFeng]

Summary

• avoid adding __webpack_require__ to chunk_link.exports when module chunk loading will export it via runtime module
• record that export strategy in ChunkLinkContext during link and let render consume link metadata instead of scanning runtime modules
• add an esmOutputCases regression for runtimeChunk: false with a shared CJS chunk, which reproduces the duplicate export failure without the fix

Related links

• fix(deps): update all non-major dependencies rstackjs/rspack-dev-server#166

Checklist

• Tests updated (or not required).
• Documentation updated (or not required).

[github-actions]

📝 Ecosystem CI detail: Open

suite	result
rspress	✅ success
modernjs	✅ success
examples	✅ success
rsbuild	✅ success
rsdoctor	✅ success
lynx-stack	❌ failure
rsbuild-rsc-plugin	✅ success
devserver	✅ success
rslib	✅ success
rstest	✅ success
plugin	✅ success

[JSerFeng]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. More of your lovely PRs please.

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[Copilot]

Pull request overview

This PR fixes a duplicate __webpack_require__ ESM export that can occur in modern-module / ESM library output, especially when optimization.runtimeChunk: false causes entry chunks to carry runtime and be imported by other chunks.

Changes:

• Avoids adding __webpack_require__ to ESM-library chunk exports when ExportRequireRuntimeModule will already export it.
• Records the export strategy on ChunkLinkContext during link, and uses that metadata during render instead of scanning runtime modules.
• Adds a regression esmOutputCases test for runtimeChunk: false with a shared CJS module to reproduce the duplicate-export failure.

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
crates/rspack_plugin_runtime/src/helpers.rs	Adds a shared helper to decide when module chunk loading should export __webpack_require__.
crates/rspack_plugin_runtime/src/module_chunk_loading.rs	Uses the shared helper to keep the export decision consistent across runtime requirements hooks.
crates/rspack_plugin_esm_library/src/chunk_link.rs	Extends ChunkLinkContext with exports_require_via_runtime_module metadata.
crates/rspack_plugin_esm_library/src/link.rs	Sets the new link metadata and prevents adding a redundant __webpack_require__ chunk export in the affected cases.
crates/rspack_plugin_esm_library/src/render.rs	Consumes link metadata to decide whether to emit a direct __webpack_require__ export.
tests/rspack-test/esmOutputCases/dynamic-import/import-cjs-runtime-chunk-false-entry-export/shared.js	Adds a shared CJS module used by both the entry and a dynamically imported module.
tests/rspack-test/esmOutputCases/dynamic-import/import-cjs-runtime-chunk-false-entry-export/dynamic.js	Dynamic import path that consumes the shared CJS module.
tests/rspack-test/esmOutputCases/dynamic-import/import-cjs-runtime-chunk-false-entry-export/index.js	Entry test that exports a value and triggers the problematic runtime/export interaction.
tests/rspack-test/esmOutputCases/dynamic-import/import-cjs-runtime-chunk-false-entry-export/rspack.config.js	Overrides optimization.runtimeChunk to false to reproduce the issue.
tests/rspack-test/esmOutputCases/dynamic-import/import-cjs-runtime-chunk-false-entry-export/__snapshots__/esm.snap.txt	Captures the corrected output (single __webpack_require__ export) for regression coverage.

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[codspeed-hq]

Merging this PR will degrade performance by 2.87%

⚡ 1 improved benchmark
❌ 3 regressed benchmarks
✅ 19 untouched benchmarks
⏩ 3 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Simulation	js@Traverse module graph by connections	279.8 µs	262.5 µs	+6.59%
❌	Simulation	js@Traverse module graph by dependencies	528.1 µs	543.7 µs	-2.87%
❌	Memory	bundle@threejs-production-sourcemap	48.7 MB	49.7 MB	-1.96%
❌	Memory	bundle@threejs-development	19.5 MB	19.8 MB	-1.42%

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_{Comparing JSerFeng:fy/fix-duplicate-runtime-export (0b918d9) with main (418eeeb)}

Footnotes

1. 3 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩