InternalSourceMap replaces serialized VLQ maps (
b2d3f5d)
Bun now stores source mappings in a private bit-packed InternalSourceMap blob instead of decoding whole VLQ maps into memory first. The new format uses fixed-size windows plus varint deltas, which cuts lookup overhead and memory churn for stack-trace/source-map remapping.
Source-map loading and stack-trace remapping now read the blob in place (b2d3f5d)
The standalone/runtime paths were updated to validate and consume the serialized blob directly, rather than parsing mappings into Mapping.List. That means find(line, col) can work without a full decode pass, which is especially important for large transpiled modules and error stacks.
Benchmark and round-trip coverage added for the new format (b2d3f5d)
This change also adds a dedicated microbench plus new internal/bundler tests to exercise the storage format and remapping behavior. That helps verify the binary encoding stays correct and makes performance regressions easier to spot.
Other misc changes
- Source-map plumbing updated across runtime, coverage, and stack-trace code
- New internal source-map helpers/tests and standalone serialization header adjustments
- Minor test/config tweaks and benchmark ignore file