[compiler] Support optional/logical/etc within try/catch

[everettbu]

Mirror of facebook/react#35606
Original author: josephsavona

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Adds support for value terminals (optional/logical/ternary/sequence) within try/catch clauses.

Try/catch expressions insert maybe-throw terminals after each instruction, but BuildReactiveFunction's value block extraction was not expecting these terminals. The fix is to roughly treat maybe-throw similarly to goto, falling through to the continuation block, but there are a few edge cases to handle.

I've also added extensive tests, including testing that errors correctly flow to the catch handler.

[greptile-apps]

Greptile Overview

Greptile Summary

Added support for value terminals (optional chaining, logical expressions, ternary, sequence expressions) within try/catch blocks by handling maybe-throw terminals in the value block extraction logic.

Key changes:

• Refactored visitValueBlock in BuildReactiveFunction.ts to handle maybe-throw terminals by treating them similarly to goto terminals, falling through to continuation blocks
• Extracted common logic into helper methods: wrapWithSequence, extractValueBlockResult, and visitTestBlock
• Added maybe-throw terminal support to findOptionalPlaces functions in DropManualMemoization.ts and ValidateExhaustiveDependencies.ts
• Converted 4 previously failing error tests to passing tests
• Added 7 new comprehensive test cases covering various combinations of value terminals within try/catch

Test coverage:
Tests validate that value blocks correctly handle error flow to catch handlers, including edge cases like nested optional chaining, logical operators combined with optional chaining, and multiple value blocks within the same try/catch.

Confidence Score: 4/5

• Safe to merge with thorough testing - comprehensive test coverage validates the implementation
• Well-structured refactoring with extensive test coverage demonstrating correct behavior. The core implementation is complex but follows consistent patterns. Tests validate error handling and edge cases thoroughly.
• Pay close attention to BuildReactiveFunction.ts - the visitValueBlock logic handles multiple edge cases around maybe-throw terminals

Important Files Changed

Filename	Overview
compiler/packages/babel-plugin-react-compiler/src/ReactiveScopes/BuildReactiveFunction.ts	Major refactor to support value terminals within try/catch - adds helper methods and handles maybe-throw terminals in value blocks
compiler/packages/babel-plugin-react-compiler/src/Inference/DropManualMemoization.ts	Adds maybe-throw terminal handling to findOptionalPlaces, following continuation block
compiler/packages/babel-plugin-react-compiler/src/Validation/ValidateExhaustiveDependencies.ts	Adds maybe-throw terminal handling to findOptionalPlaces, following continuation block
compiler/packages/babel-plugin-react-compiler/src/tests/fixtures/compiler/try-catch-optional-chaining.js	New test for optional chaining within try/catch, validates error handling
compiler/packages/babel-plugin-react-compiler/src/tests/fixtures/compiler/try-catch-logical-and-optional.js	New test combining logical && with optional chaining in try/catch, validates error flow

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[everettbu]

Upstream PR was closed or merged. Code is synced via branch mirror.