Preserve tagged-template call, aliasing, and mutation effects instead of assuming no-substitution tags are primitive or pure.
Execute opaque or effectful tags unconditionally while retaining memoization only when a configured signature proves a read-only pure call and safe return.
AI-assisted investigation and implementation; reviewed and understood by the contributor.
## Summary
`oxc_react_compiler` had no committed test over the upstream React
Compiler fixture corpus — the fixtures lived only in the
`oxc-project/forked-react-compiler` checkout, exercised out-of-tree.
That gap let real regressions slip past the 15 in-crate integration
tests. This PR closes it.
- **`crates/oxc_react_compiler/fixtures/`** — 1734 fixture *input* files
(`.js`/`.ts`/`.tsx`/`.jsx`/`.mjs`), copied from the fork's
`babel-plugin-react-compiler/src/__tests__/fixtures/compiler` tree with
subdirectories preserved. Flow fixtures (the `@flow`-pragma ones) are
excluded — oxc has no Flow parser. The upstream `.expect.md` goldens are
also not copied; insta is the golden here.
- **`crates/oxc_react_compiler/tests/snapshot.rs`** — an `insta::glob!`
test that, per fixture, derives `PluginOptions`/`EnvironmentConfig` from
the first-line `// @directive` pragmas (base `compilationMode=all` /
`panicThreshold=all_errors`, matching the upstream `snap` runner),
parses → builds semantic → runs `transform`, and snapshots the compiled
output plus diagnostics. Unrecognised directives are ignored, as
upstream does; camelCase flag directives map to `EnvironmentConfig`
fields via `convert_case`.
- **`crates/oxc_react_compiler/tests/snapshots/`** — 1734 committed
`.snap` goldens (oxc's own output).
- **`.typos.toml`** — excludes the fixtures dir (the upstream fixtures
contain intentional typos; `**/*.snap` was already excluded).
These snapshots are oxc's own golden output, so `cargo test` (and CI)
now catches any change in compiler behaviour across the corpus.
Regenerate after an intended change with `cargo insta accept`.
## Verification
- `cargo test -p oxc_react_compiler` passes — the 1734-fixture snapshot
test plus the existing 15 integration tests; also green under
`--all-features` (matches the cross-target CI job).
- clippy `-D warnings`, `cargo fmt`, and `typos` clean.
- No fixture panics; 1336 compiled / 398 unchanged / 335 with
diagnostics.
- The `error.*` fixtures capture the exact diagnostics — including the
"Cannot reassign variable after render" error that a recent scoping
change had silently suppressed, confirming the suite catches real
regressions.
---
AI usage disclosure: authored with Claude Code and reviewed before
submission.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
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