Remove unstable_compactSourceMaps; always store compact VLQ source maps (#1765)#1765
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Remove unstable_compactSourceMaps; always store compact VLQ source maps (#1765)#1765robhogan wants to merge 3 commits into
unstable_compactSourceMaps; always store compact VLQ source maps (#1765)#1765robhogan wants to merge 3 commits into
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…ults to `true` Differential Revision: D110759649
Summary: The whole-bundle source map served by Metro (the `.map` endpoint, inline source maps, and RAM bundle info) can be emitted either as a flat map or as an indexed/sectioned map. The indexed form passes each module's stored VLQ `mappings` through verbatim instead of decoding and re-encoding them into one flat map, so it is much cheaper to serialize; the flat form was only kept for consumers that predate index-map support. This was gated behind `serializer.unstable_allowIndexMap` (default off) and additionally only took effect when at least one module actually stored a compact VLQ map (`shouldEmitIndexedMap` checked `some(isVlqMap)`). Index maps are now safe to emit unconditionally, so this removes the choice: - Deletes the `serializer.unstable_allowIndexMap` option (default, Flow type, and generated TS type). - Removes `shouldEmitIndexedMap` and the `some(isVlqMap)` guard from `sourceMapGenerator`; both `sourceMapGenerator` and `sourceMapGeneratorNonBlocking` now always call `fromRawMappingsIndexed`. `fromRawMappingsIndexed`/`toIndexMapSection` already handle every input shape (VLQ maps pass through verbatim; tuple maps are re-encoded per section), so no change is needed there. - Drops the now-dead `allowIndexMap` plumbing from `Server.js` and the `unstable_allowIndexMap` wiring in the fb-metro CLI (the `--experimental-compact-source-maps` flag still controls `transformer.unstable_compactSourceMaps`, which is what determines VLQ storage). Behavioral change: the bundle `.map` (and inline/RAM-bundle maps) is now always a sectioned index map, whereas previously it defaulted to a flat map. This is the intended graduation of the index-map path; consumers on this toolchain already understand index maps. Scope note — this does NOT make the flat serialization functions dead: `fromRawMappings` is still called directly by `metro-transform-worker` and `metro-buck-transform-worker` for single-module maps, and `fromRawMappings`/`fromRawMappingsNonBlocking`/`isVlqMap`/`toBabelSegments` remain public exports of `metro-source-map`. Only the serializer's flat-vs-indexed *choice* is removed. `fromRawMappingsNonBlocking` is now internally unused but retained as public API; removing it would be a separate, deliberate API break. Differential Revision: D110757150
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…maps (#1765) Summary: Pull Request resolved: #1765 `unstable_compactSourceMaps` gated whether the transform worker stored each module's source map as a compact VLQ `VlqMap` (`{mappings, names}`) or as decoded `MetroSourceMapSegmentTuple[]`. Its default was flipped to `true` earlier in this stack; this removes the option entirely and makes compact VLQ storage unconditional. - Deletes the `transformer.unstable_compactSourceMaps` option (Flow type, metro-config default, and generated TS type). - Simplifies `transformJS`/`transformJSON` to always encode a `VlqMap`: the Babel decoded-map fast path when not minifying, re-encoding the minifier's tuples otherwise. - Narrows `JsOutput.data.map` from `Array<MetroSourceMapSegmentTuple> | VlqMap` to `VlqMap` and regenerates the TS defs. `unstable_compactSourceMaps` was recently introduced and has never appears in an OSS release. Changelog: ``` - **[Breaking]** Transformer output (`JsOutput['data']['map']`) is now always a `VlqMap` ```` Reviewed By: GijsWeterings Differential Revision: D110762248
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unstable_compactSourceMaps; always store compact VLQ source mapsunstable_compactSourceMaps; always store compact VLQ source maps (#1765)
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@robhogan has exported this pull request. If you are a Meta employee, you can view the originating Diff in D110762248. |
…maps (#1765) Summary: Pull Request resolved: #1765 `unstable_compactSourceMaps` gated whether the transform worker stored each module's source map as a compact VLQ `VlqMap` (`{mappings, names}`) or as decoded `MetroSourceMapSegmentTuple[]`. Its default was flipped to `true` earlier in this stack; this removes the option entirely and makes compact VLQ storage unconditional. - Deletes the `transformer.unstable_compactSourceMaps` option (Flow type, metro-config default, and generated TS type). - Simplifies `transformJS`/`transformJSON` to always encode a `VlqMap`: the Babel decoded-map fast path when not minifying, re-encoding the minifier's tuples otherwise. - Narrows `JsOutput.data.map` from `Array<MetroSourceMapSegmentTuple> | VlqMap` to `VlqMap` and regenerates the TS defs. `unstable_compactSourceMaps` was recently introduced and has never appears in an OSS release. Changelog: ``` - **[Breaking]** Transformer output (`JsOutput['data']['map']`) is now always a `VlqMap` ```` Reviewed By: GijsWeterings Differential Revision: D110762248
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Summary:
unstable_compactSourceMapsgated whether the transform worker stored each module's source map as a compact VLQVlqMap({mappings, names}) or as decodedMetroSourceMapSegmentTuple[]. Its default was flipped totrueearlier in this stack; this removes the option entirely and makes compact VLQ storage unconditional.transformer.unstable_compactSourceMapsoption (Flow type, metro-config default, and generated TS type).transformJS/transformJSONto always encode aVlqMap: the Babel decoded-map fast path when not minifying, re-encoding the minifier's tuples otherwise.JsOutput.data.mapfromArray<MetroSourceMapSegmentTuple> | VlqMaptoVlqMapand regenerates the TS defs.unstable_compactSourceMapswas recently introduced and has never appears in an OSS release.Changelog:
Reviewed By: GijsWeterings
Differential Revision: D110762248