Fixed detection of optional chains containing a reference - #64232
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Mateusz Burzyński (Andarist) wants to merge 3 commits into
Open
Fixed detection of optional chains containing a reference#64232Mateusz Burzyński (Andarist) wants to merge 3 commits into
Mateusz Burzyński (Andarist) wants to merge 3 commits into
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Mateusz Burzyński (Andarist)
September 10, 2026 16:54
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🟡 Changes recommended
The operand reversal regresses narrowing when an optional-chain base is wrapped in a satisfies expression.
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Pull request overview
Fixes control-flow narrowing for references assigned within optional-chain bases.
Changes:
- Reverses reference matching to recognize assignment targets.
- Adds regression and negative narrowing tests with baselines.
File summaries
| File | Description |
|---|---|
tsc/internal/checker/flow.go |
Updates optional-chain reference matching. |
tsc/testdata/tests/cases/conformance/controlFlow/controlFlowOptionalChain4.ts |
Adds regression cases. |
tsc/testdata/baselines/reference/conformance/controlFlowOptionalChain4.types |
Records inferred types. |
tsc/testdata/baselines/reference/conformance/controlFlowOptionalChain4.symbols |
Records resolved symbols. |
tsc/testdata/baselines/reference/conformance/controlFlowOptionalChain4.errors.txt |
Records expected diagnostics. |
Review details
- Files reviewed: 5/5 changed files
- Comments generated: 1
- Review effort level: Balanced
Mateusz Burzyński (Andarist)
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fixes #56998
fixes #60855
recreates #59144