Turbopack: Use FrozenMap for module export information#92802
Merged
Conversation
nextjs-bot
added
created-by: Turbopack team
Contributor
Tests Passed |
Merging this PR will not alter performance
Comparing 
Footnotes
|
mischnic
reviewed
Apr 14, 2026
|
|
||
| let exports = EsmExports { | ||
| exports, | ||
| exports: FrozenMap::from_unique_sorted_box(exports.into_boxed_slice()), |
Member
There was a problem hiding this comment.
So this "from sorted box" hinges on esm_exports.exports being a sorted vec already.
So if somebody accidentally changes esm_exports.exports to be a different key-value collection, then this would silently break?
Member
Author
There was a problem hiding this comment.
Contributor
Stats from current PR✅ No significant changes detected📊 All Metrics📖 Metrics GlossaryDev Server Metrics:
Build Metrics:
Change Thresholds:
⚡ Dev Server
📦 Dev Server (Webpack) (Legacy)📦 Dev Server (Webpack)
⚡ Production Builds
📦 Production Builds (Webpack) (Legacy)📦 Production Builds (Webpack)
📦 Bundle SizesBundle Sizes⚡ TurbopackClient Main Bundles
Server Middleware
Build DetailsBuild Manifests
📦 WebpackClient Main Bundles
Polyfills
Pages
Server Edge SSR
Middleware
Build DetailsBuild Manifests
Build Cache
🔄 Shared (bundler-independent)Runtimes
📎 Tarball URL |
lukesandberg
approved these changes
Apr 15, 2026
mischnic
approved these changes
Apr 15, 2026
This was referenced Apr 23, 2026
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to subscribe to this conversation on GitHub.
Already have an account?
Sign in.
4 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
FrozenMapshould be a bit smaller than storing these all asBTreeMaps. Iteration order is identical (both use sorted order).https://turbopack-rust-docs.vercel.sh/rustdoc/turbo_frozenmap/map/struct.FrozenMap.html