[gkz]

Summary:
@public
Upgrade flow-parser, flow-estree, flow-eslint, flow-transform and flow-api-translator to 0.340.0, and adapt the code generators, codemods, lint rules and parser adapters that read the ESTree output those releases produce.

Four shapes moved since the versions in use, and each one silently changed behavior rather than failing loudly:

• Generic type annotations carry their arguments in typeArguments instead of typeParameters, so consumers that still read the old field dropped every type argument. Readers now take the canonical field whenever the node carries it, including when it is null, and fall back to the previous field otherwise, so the same source keeps working with the older releases that remain installed elsewhere.
• Enum declarations expose a single EnumBody carrying an explicit type instead of one node type per value kind. Enum readers accept both and resolve the value kind the same way, so the supported enums and the existing rejection of boolean and symbol enums are unchanged.
• JSXAttribute.name widened to also allow a namespaced name, so transforms that compare an attribute name against a list now match only plain identifiers and leave namespaced attributes alone, which is what they already did at runtime.
• Object type properties, array elements, import phases and several other fields are now nullable or newly required. Readers guard them and report the existing unsupported-input errors instead of failing on a missing property, and import declarations are built from constant parser-owned templates so one source satisfies both the old and the new builder.

The lint rules, the declaration generators and the jscodeshift/recast boundary are adapted the same way, and the published type mirrors for the lint and transform packages are refreshed.

Changelog: [Internal]

Reviewed By: SamChou19815, panagosg7

Differential Revision: D131489493

[meta-codesync]

@gkz has exported this pull request. If you are a Meta employee, you can view the originating Diff in D131489493.

[github-actions]

Metro review: Looks good

Risk: low · Commit: ddbfa1b · 8 commands run

This PR bumps flow-parser, flow-estree, flow-eslint, flow-transform and flow-api-translator from 0.336.0 to 0.340.0. It also strips a leading hashbang before the TypeScript definition generator runs files through flow-api-translator, because translator 0.340.0 throws on hashbang files such as metro-symbolicate/src/index.js. Generated .d.ts files, API snapshots and the hermes-parser path in metro-babel-transformer all behave the same as on the base. Most of the adaptation work the description lists (lint rules, enum readers, codemods) isn't in this OSS diff, and the description doesn't mention the hashbang workaround, which is the only code change here.

No findings.

Verified

• ✅ yarn jest --no-watchman scripts/__tests__/declaration-input-test.js — 4/4 new tests pass
• ✅ node bench/hb.js <head|base> (translateFlowToFlowDef on raw packages/metro-symbolicate/src/index.js) (failed as expected) — Head 0.340.0 throws "Cannot read properties of undefined (reading '1')"; base 0.336.0 succeeds. This confirms the hashbang strip is needed.
• ✅ yarn build-ts-defs && git status --short — The generator ran without errors and left the working tree clean, so the committed .d.ts files match 0.340.0 output. The lint messages it printed are part of its normal unused-declaration pruning.
• ✅ node bench/babelparse.js on head and base (flow-parser babel:true + Babel transform: hashbang, enum, generics, JSX namespace, import type) — Head and base output is identical for every sample
• ✅ yarn jest --no-watchman scripts packages/metro-babel-transformer packages/metro-babel-register packages/metro/src/ModuleGraph packages/metro-transform-worker — 16 suites, 382 passed, 1 skipped
• ✅ yarn typecheck
• ✅ yarn lint scripts/generateTypeScriptDefinitions.js scripts/__tests__/declaration-input-test.js — 0 errors. The 1 warning is in an unchanged test file and predates this PR.
• ✅ yarn verify-api-snapshots — 18 snapshots verified

Not run: No benchmark: this is a parser version bump plus a script-only change, with no performance claim. The full Jest suite and the integration bundles weren't run; only the suites that touch the parser and the scripts were. Windows wasn't checked; the hashbang regex already handles CRLF and is covered by a test.

_{Automated review by Claude. Advisory only: it never approves or blocks, and a maintainer makes the call.}