[Jake Bailey (jakebailey)]

Fixes #63831

[Copilot]

🟡 Changes recommended

The modified completion and hover behaviors lack required fourslash regression coverage.

Get a fresh assessment by requesting another Copilot review.

Pull request overview

Preserves valid numeric syntax for infinite numeric literals across declaration emit, enum transforms, type display, and language-service output.

Changes:

• Emits 1e999/-1e999 instead of shadowable Infinity.
• Preserves source spelling for directly const-asserted numeric literals.
• Adds compiler tests and updates affected baselines.

File summaries

File	Description
tsc/testdata/tests/cases/compiler/fakeInfinity2.ts	Tests shadowed Infinity with enum emit.
tsc/testdata/tests/cases/compiler/declarationEmitNegativeNumericConstLiterals.ts	Tests numeric const declaration emit.
tsc/testdata/tests/cases/compiler/constEnumInfinityShadow.ts	Tests const-enum inlining with shadowing.
tsc/testdata/baselines/reference/conformance/octalIntegerLiteralES6.types	Updates infinite octal type display.
tsc/testdata/baselines/reference/conformance/octalIntegerLiteral(target=es2015).types	Updates ES2015 octal display.
tsc/testdata/baselines/reference/conformance/enumConstantMembers.js	Updates infinite enum emit.
tsc/testdata/baselines/reference/conformance/binaryIntegerLiteralES6.types	Updates infinite binary type display.
tsc/testdata/baselines/reference/conformance/binaryIntegerLiteral(target=es2015).types	Updates ES2015 binary display.
tsc/testdata/baselines/reference/compiler/fakeInfinity3.types	Updates inferred infinite types.
tsc/testdata/baselines/reference/compiler/fakeInfinity3.js	Verifies shadow-safe declarations and emit.
tsc/testdata/baselines/reference/compiler/fakeInfinity2.types	Updates types and added enum coverage.
tsc/testdata/baselines/reference/compiler/fakeInfinity2.symbols	Records added test symbols.
tsc/testdata/baselines/reference/compiler/fakeInfinity2.js	Verifies shadow-safe enum output.
tsc/testdata/baselines/reference/compiler/fakeInfinity1.types	Updates infinite literal type formatting.
tsc/testdata/baselines/reference/compiler/fakeInfinity1.errors.txt	Updates diagnostic type spelling.
tsc/testdata/baselines/reference/compiler/deferredConditionalTypes2.types	Updates conditional-type displays.
tsc/testdata/baselines/reference/compiler/declarationEmitNegativeNumericConstLiterals.types	Records inferred numeric types.
tsc/testdata/baselines/reference/compiler/declarationEmitNegativeNumericConstLiterals.symbols	Records regression-test symbols.
tsc/testdata/baselines/reference/compiler/declarationEmitNegativeNumericConstLiterals.js	Verifies declaration spelling preservation.
tsc/testdata/baselines/reference/compiler/declarationEmitEnumNaN.js	Updates infinite enum declarations.
tsc/testdata/baselines/reference/compiler/constEnumInfinityShadow.types	Records const-enum inferred types.
tsc/testdata/baselines/reference/compiler/constEnumInfinityShadow.symbols	Records const-enum symbols.
tsc/testdata/baselines/reference/compiler/constEnumInfinityShadow.js	Verifies shadow-safe const-enum inlining.
tsc/testdata/baselines/reference/compiler/constEnumInfinityShadow.errors.txt	Records expected non-finite diagnostic.
tsc/internal/transformers/tstransforms/utilities.go	Emits overflow numeric literals for infinity.
tsc/internal/transformers/inliners/constenum.go	Makes const-enum inlining shadow-safe.
tsc/internal/transformers/declarations/transform.go	Makes enum declaration emit shadow-safe.
tsc/internal/ls/completions.go	Formats infinite exhaustive-case snippets.
tsc/internal/jsnum/string.go	Defines canonical infinity literal text.
tsc/internal/checker/pseudotypenodebuilder.go	Restores const-assertion source spelling.
tsc/internal/checker/nodecopy.go	Preserves overflowing computed-name text.
tsc/internal/checker/nodebuilderimpl.go	Emits valid infinite literal type nodes.
tsc/internal/checker/nodebuilder_hover.go	Formats infinite enum hover initializers.
tsc/internal/checker/emitresolver.go	Emits shadow-safe literal constants.

Review details

• Files reviewed: 34/34 changed files
• Comments generated: 2
• Review effort level: Balanced

[Copilot]

🔵 Needs a closer look

The changed completion and expandable-hover behaviors need dedicated fourslash regression coverage.

2 open findings

• This changes exhaustive-switch completion output for infinite numeric literal unions, but the PR…
• This changes language-service rendering of expanded enum initializers, but none of the added…

🧠 Review effort: Balanced