fix: avoid panic on untranspiled JSX syntax by reporting a diagnostic error by IWANABETHATGUY · Pull Request #8226 · rolldown/rolldown

IWANABETHATGUY · 2026-02-07T04:55:05Z

IWANABETHATGUY · 2026-02-07T04:55:30Z

fix: avoid panic on untranspiled JSX syntax by reporting a diagnostic error #8226 👈 (View in Graphite)
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crates/rolldown/src/utils/tweak_ast_for_scanning.rs

Copilot

Pull request overview

Fixes a crash when rolldown’s AST scanning encounters untranspiled JSX/TS syntax (e.g. during SSR dep scanning) by turning previous unreachable!() paths into a conservative “has side effects” result and emitting a dedicated diagnostic instead.

Changes:

Introduces UNTRANSPILED_SYNTAX diagnostic kind/event and constructor plumbing in rolldown_error.
Tracks untranspiled JSX/TypeScript syntax during scanning/side-effect detection and reports it instead of panicking.
Adds an integration fixture for issue #8216 to assert the diagnostic behavior.

Reviewed changes

Copilot reviewed 16 out of 17 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
crates/rolldown_error/src/types/event_kind.rs	Adds `UntranspiledSyntaxError` event kind and display string.
crates/rolldown_error/src/generated/event_kind_switcher.rs	Extends the generated event kind switcher bitflag for the new event.
crates/rolldown_error/src/build_diagnostic/events/untranspiled_syntax.rs	Adds a new build event producing the untranspiled syntax diagnostic message.
crates/rolldown_error/src/build_diagnostic/events/mod.rs	Registers the new `untranspiled_syntax` event module.
crates/rolldown_error/src/build_diagnostic/constructors.rs	Adds `BuildDiagnostic::untranspiled_syntax(...)` constructor.
crates/rolldown_common/src/inner_bundler_options/types/transform_option/mod.rs	Adds a debug-only `jsx_preset` override to transform options (test-focused).
crates/rolldown_common/src/inner_bundler_options/mod.rs	Adds debug-only deserialization for `transform.jsxPreset`.
crates/rolldown_binding/src/utils/normalize_binding_transform_options.rs	Aligns binding-side option normalization with the debug-only `jsx_preset` field.
crates/rolldown/tests/rolldown/issues/8216/main.jsx	Adds fixture input containing JSX.
crates/rolldown/tests/rolldown/issues/8216/artifacts.snap	Adds snapshot asserting `UNTRANSPILED_SYNTAX` error output.
crates/rolldown/tests/rolldown/issues/8216/_config.json	Adds fixture config to reproduce untranspiled JSX detection.
crates/rolldown/src/utils/tweak_ast_for_scanning.rs	Removes a TS-related `unreachable!()` in AST preprocessing.
crates/rolldown/src/utils/prepare_build_context.rs	Allows debug-only override of derived JSX preset in build context prep.
crates/rolldown/src/stages/link_stage/cross_module_optimization.rs	Propagates untranspiled-syntax tracking from side-effect detection and reports diagnostics in link stage.
crates/rolldown/src/ast_scanner/side_effect_detector/mod.rs	Replaces JSX/TS `unreachable!()`s with conservative behavior + untranspiled-syntax tracking.
crates/rolldown/src/ast_scanner/mod.rs	Tracks untranspiled TypeScript syntax in scanner instead of panicking.
crates/rolldown/src/ast_scanner/impl_visit.rs	Accumulates untranspiled syntax during AST traversal and emits diagnostics after scanning.

crates/rolldown/src/ast_scanner/impl_visit.rs

Copilot

Pull request overview

Copilot reviewed 15 out of 16 changed files in this pull request and generated 1 comment.

crates/rolldown_common/src/inner_bundler_options/types/transform_option/mod.rs

github-actions · 2026-02-08T14:35:44Z

Benchmarks Rust

target: main(ef8bc2a)
pr: 02-07-fix_8216(20bbcbc)

group                                                        pr                                     target
-----                                                        --                                     ------
bundle/bundle@multi-duplicated-top-level-symbol              1.00     67.2±1.94ms        ? ?/sec    1.04     70.1±1.80ms        ? ?/sec
bundle/bundle@multi-duplicated-top-level-symbol-sourcemap    1.00     73.2±1.96ms        ? ?/sec    1.05     76.9±2.48ms        ? ?/sec
bundle/bundle@rome_ts                                        1.00     99.5±2.03ms        ? ?/sec    1.01    100.7±2.15ms        ? ?/sec
bundle/bundle@rome_ts-sourcemap                              1.00    110.7±2.31ms        ? ?/sec    1.02    112.4±1.75ms        ? ?/sec
bundle/bundle@threejs                                        1.00     35.8±2.15ms        ? ?/sec    1.01     36.1±2.07ms        ? ?/sec
bundle/bundle@threejs-sourcemap                              1.00     39.9±0.54ms        ? ?/sec    1.02     40.9±0.84ms        ? ?/sec
bundle/bundle@threejs10x                                     1.00    365.0±5.82ms        ? ?/sec    1.01    368.2±4.72ms        ? ?/sec
bundle/bundle@threejs10x-sourcemap                           1.00    418.7±9.48ms        ? ?/sec    1.02    425.4±5.65ms        ? ?/sec
scan/scan@rome_ts                                            1.00     79.4±1.57ms        ? ?/sec    1.01     79.8±1.62ms        ? ?/sec
scan/scan@threejs                                            1.00     28.0±1.64ms        ? ?/sec    1.01     28.3±1.83ms        ? ?/sec
scan/scan@threejs10x                                         1.00    282.4±4.13ms        ? ?/sec    1.03    290.0±6.97ms        ? ?/sec

crates/rolldown/src/ast_scanner/impl_visit.rs

graphite-app · 2026-02-08T16:06:19Z

Merge activity

Feb 8, 4:06 PM UTC: IWANABETHATGUY added this pull request to the Graphite merge queue.
Feb 8, 4:19 PM UTC: Merged by the Graphite merge queue.

… error (#8226) Closed #8216

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@sapphi-red

## [1.0.0-rc.4] - 2026-02-11 💡 Granular `comments` Option - New `output.comments` option provides fine-grained control over comment preservation - The `output.legalComments` option is now deprecated and use `comments.legal` instead ### 🚀 Features - rename error name to `RolldownError` from `RollupError` (#8262) by @sapphi-red - add hidden `resolve_tsconfig` function for Vite (#8257) by @sapphi-red - rust: introduce `rolldown_watcher` (#8161) by @hyf0 - unify `comments` and `legalComments` into a single granular `comments` option (#8229) by @IWANABETHATGUY - add builtin plugin for visualizing chunk graph (#8162) by @IWANABETHATGUY - show import declaration location in AssignToImport errors (#8222) by @Copilot - show import declaration span in CannotCallNamespace error (#8223) by @Copilot - emit error when plugin accidentally removes runtime module symbols (#8203) by @IWANABETHATGUY - support tsconfig loading & inputMap for `transform` (#8180) by @sapphi-red - rolldown_plugin_vite_reporter: update warning message to link to Rolldown docs (#8205) by @sapphi-red ### 🐛 Bug Fixes - avoid panic on untranspiled JSX syntax by reporting a diagnostic error (#8226) by @IWANABETHATGUY - rolldown_plugin_vite_import_glob: relax absolute path check and improve invalid glob warning (#8219) by @shulaoda - merge chunks after detect circular reference (#8154) by @IWANABETHATGUY - rust: detect runtime module side effects based on its content (#8209) by @hyf0 ### 🚜 Refactor - rename `other` to `jsdoc` in comments options (#8256) by @IWANABETHATGUY - rename chunk-visualize plugin with bundle-analyzer plugin (#8255) by @IWANABETHATGUY - remove EXPORT_UNDEFINED_VARIABLE error (#8228) by @Copilot - consolidate missing runtime symbol errors into a single diagnostic (#8220) by @IWANABETHATGUY - stabilize `parse` and `parseSync` (#8215) by @sapphi-red - return errors instead of panicking on builtin plugin conversion failure (#8217) by @shulaoda - expose `parse` / `minify` / `transform` from `rolldown/utils` (#8214) by @sapphi-red - prepare defer chunk merging (#8153) by @IWANABETHATGUY ### 📚 Documentation - remove `<script>` escape behavior difference note from `platform` option (#8253) by @sapphi-red - TypeScript & JSX support by plugins (#8183) by @sapphi-red ### 🧪 Testing - ensure runtime module is preserved even if it's not used but has side effects (#8213) by @hyf0 ### ⚙️ Miscellaneous Tasks - deps: update oxc to v0.113.0 (#8267) by @renovate[bot] - deps: update dependency oxlint-tsgolint to v0.12.0 (#8272) by @renovate[bot] - deps: update oxc apps (#8269) by @renovate[bot] - deps: update test262 submodule for tests (#8261) by @sapphi-red - deps: update crate-ci/typos action to v1.43.4 (#8260) by @renovate[bot] - deps: update dependency esbuild to v0.27.3 (#8250) by @renovate[bot] - deps: update rust crates (#8244) by @renovate[bot] - deps: update dependency semver to v7.7.4 (#8247) by @renovate[bot] - deps: update github-actions (#8243) by @renovate[bot] - deps: update npm packages (#8245) by @renovate[bot] - deps: update oxc resolver to v11.17.1 (#8240) by @renovate[bot] - deps: update rust crate oxc_sourcemap to v6.0.2 (#8241) by @renovate[bot] - rust: handle ignored `RUSTSEC-2025-0141` cargo check error (#8235) by @hyf0 - deps: update dependency oxlint-tsgolint to v0.11.5 (#8233) by @renovate[bot] - deps: update dependency rolldown-plugin-dts to ^0.22.0 (#8232) by @renovate[bot] - deps: update crate-ci/typos action to v1.43.3 (#8225) by @renovate[bot] - deps: update dependency rolldown-plugin-dts to v0.21.9 (#8224) by @renovate[bot] - deps: update crate-ci/typos action to v1.43.2 (#8212) by @renovate[bot] - remove rolldown_plugin_vite_wasm_helper (#8207) by @shulaoda - build docs for production (#8206) by @sapphi-red Co-authored-by: shulaoda <165626830+shulaoda@users.noreply.github.com>

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IWANABETHATGUY force-pushed the 02-07-fix_8216 branch 4 times, most recently from b418422 to 7aae85c Compare February 8, 2026 06:12

IWANABETHATGUY commented Feb 8, 2026

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IWANABETHATGUY changed the title ~~fix: 8216~~ feat: detect and report untranspiled TypeScript and JSX syntax Feb 8, 2026

IWANABETHATGUY changed the title ~~feat: detect and report untranspiled TypeScript and JSX syntax~~ fix: avoid panic on untranspiled JSX syntax by reporting a diagnostic error Feb 8, 2026

IWANABETHATGUY marked this pull request as ready for review February 8, 2026 07:47

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fix: avoid panic on untranspiled JSX syntax by reporting a diagnostic…

20bbcbc

… error (#8226) Closed #8216

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graphite-app bot merged commit 20bbcbc into main Feb 8, 2026
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graphite-app bot deleted the 02-07-fix_8216 branch February 8, 2026 16:19

This was referenced Feb 11, 2026

release: v1.0.0-rc.4 #8271

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release: v1.0.0-rc.4 #8278

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fix: avoid panic on untranspiled JSX syntax by reporting a diagnostic error#8226

fix: avoid panic on untranspiled JSX syntax by reporting a diagnostic error#8226
graphite-app[bot] merged 1 commit intomainfrom
02-07-fix_8216

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