fix(metro-core): improve Windows metro runtime compatibility

[ScriptedAlchemy]

Description

fix(metro-core): Normalize Windows module paths for module federation

This PR addresses issues with Metro's module federation on Windows environments where native path separators (\) cause incorrect module resolution and generation. The changes ensure that generated module specifiers and internal paths are consistently normalized to POSIX-style separators (/) to prevent build failures and ensure correct module loading.

Specifically, this includes:

• Escaping the injected Babel transformer path for Windows compatibility.
• Normalizing module specifiers for runtime plugin imports, host entry imports, expose import paths, and entry regex matching in the resolver.
• Introducing a toPosixPath helper function with dedicated unit tests.

Related Issue

This PR addresses the broader problem of Windows path resolution in Metro, similar to the scope of #4442.

Types of changes

• Docs change / refactoring / dependency upgrade
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Checklist

• I have added tests to cover my changes.
• All new and existing tests passed.
• I have updated the documentation.

---

 

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[changeset-bot]

🦋 Changeset detected

Latest commit: cb3464c

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 43 packages

Name	Type
@module-federation/metro	Patch
@module-federation/metro-plugin-rnc-cli	Patch
@module-federation/metro-plugin-rnef	Patch
@module-federation/runtime	Patch
@module-federation/enhanced	Patch
@module-federation/rspack	Patch
@module-federation/webpack-bundler-runtime	Patch
@module-federation/sdk	Patch
@module-federation/runtime-tools	Patch
@module-federation/managers	Patch
@module-federation/manifest	Patch
@module-federation/dts-plugin	Patch
@module-federation/third-party-dts-extractor	Patch
@module-federation/devtools	Patch
@module-federation/bridge-react	Patch
@module-federation/bridge-vue3	Patch
@module-federation/bridge-shared	Patch
@module-federation/bridge-react-webpack-plugin	Patch
@module-federation/modern-js-v3	Patch
@module-federation/retry-plugin	Patch
@module-federation/data-prefetch	Patch
@module-federation/rsbuild-plugin	Patch
@module-federation/error-codes	Patch
@module-federation/inject-external-runtime-core-plugin	Patch
@module-federation/runtime-core	Patch
create-module-federation	Patch
@module-federation/cli	Patch
@module-federation/rspress-plugin	Patch
@module-federation/treeshake-server	Patch
@module-federation/treeshake-frontend	Patch
@module-federation/modern-js	Patch
@module-federation/nextjs-mf	Patch
@module-federation/node	Patch
@module-federation/storybook-addon	Patch
shared-tree-shaking-no-server-host	Patch
shared-tree-shaking-no-server-provider	Patch
@module-federation/esbuild	Patch
@module-federation/utilities	Patch
remote5	Patch
remote6	Patch
shared-tree-shaking-with-server-host	Patch
shared-tree-shaking-with-server-provider	Patch
website-new	Patch

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[pkg-pr-new]

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@module-federation/devtools

pnpm add https://pkg.pr.new/module-federation/core/@module-federation/devtools@cb3464c

@module-federation/cli

pnpm add https://pkg.pr.new/module-federation/core/@module-federation/cli@cb3464c

create-module-federation

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@module-federation/data-prefetch

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@module-federation/dts-plugin

pnpm add https://pkg.pr.new/module-federation/core/@module-federation/dts-plugin@cb3464c

@module-federation/enhanced

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@module-federation/error-codes

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@module-federation/managers

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@module-federation/manifest

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@module-federation/metro

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@module-federation/metro-plugin-rnc-cli

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@module-federation/metro-plugin-rnef

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@module-federation/modern-js-v3

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@module-federation/retry-plugin

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@module-federation/rsbuild-plugin

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@module-federation/rspack

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@module-federation/rspress-plugin

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@module-federation/runtime

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@module-federation/runtime-core

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@module-federation/runtime-tools

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@module-federation/third-party-dts-extractor

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@module-federation/treeshake-frontend

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@module-federation/treeshake-server

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@module-federation/webpack-bundler-runtime

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@module-federation/bridge-react

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@module-federation/bridge-react-webpack-plugin

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@module-federation/bridge-shared

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@module-federation/bridge-vue3

pnpm add https://pkg.pr.new/module-federation/core/@module-federation/bridge-vue3@cb3464c

@module-federation/inject-external-runtime-core-plugin

pnpm add https://pkg.pr.new/module-federation/core/@module-federation/inject-external-runtime-core-plugin@cb3464c

commit: cb3464c

[github-actions]

Bundle Size Report

1 package(s) changed, 40 unchanged.

Package	Total dist	Delta	ESM gzip	Delta
metro-core	225.3 kB	+6.7 kB (+3.1%)	147 B	no change

Total dist: 6.89 MB (+6.7 kB (+0.1%))
Total ESM gzip: 138.6 kB (no change)

[ScriptedAlchemy]

@jbroma hows this?

[jbroma]

Changes look good, I would still reconsider this: #4453 (comment)

In current shape, the e2e-metro-windows is not an e2e test and the tests & builds run already as part of the main workflow for whole repo