Don't defer index types for non-generic substitution types - #63914
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Mateusz Burzyński (Andarist) wants to merge 2 commits into
Open
Don't defer index types for non-generic substitution types#63914Mateusz Burzyński (Andarist) wants to merge 2 commits into
Mateusz Burzyński (Andarist) wants to merge 2 commits into
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Mateusz Burzyński (Andarist)
August 20, 2026 13:26
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Pull request overview
Fixes incorrect keyof deferral for non-generic substitution types, restoring assignability and simplified type display.
Changes:
- Resolve non-generic substitution types before computing index types.
- Add regression tests for quick info and assignability.
- Add corresponding type and symbol baselines.
Reviewed changes
Copilot reviewed 7 out of 7 changed files in this pull request and generated no comments.
Show a summary per file
| File | Description |
|---|---|
tsc/internal/checker/checker.go |
Resolves non-generic substitutions as intersections. |
tsc/testdata/tests/cases/compiler/substitutionTypeNonGenericIndexType1.ts |
Tests simplified resulting type. |
tsc/testdata/tests/cases/compiler/substitutionTypeNonGenericIndexType2.ts |
Tests corrected assignability. |
tsc/testdata/baselines/reference/compiler/substitutionTypeNonGenericIndexType1.types |
Records expected types. |
tsc/testdata/baselines/reference/compiler/substitutionTypeNonGenericIndexType1.symbols |
Records expected symbols. |
tsc/testdata/baselines/reference/compiler/substitutionTypeNonGenericIndexType2.types |
Records expected types. |
tsc/testdata/baselines/reference/compiler/substitutionTypeNonGenericIndexType2.symbols |
Records expected symbols. |
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fixes #63786
resumes the work done in #61999