From 413176b2a1a54babdd94d8baa51d996d62cee1a7 Mon Sep 17 00:00:00 2001 From: Anders Hejlsberg Date: Sat, 30 May 2015 16:37:03 -0700 Subject: [PATCH 1/4] Use symbols instead of types in infinite instantiation detection --- src/compiler/checker.ts | 123 +++++++++++++++++++++------------------- src/compiler/types.ts | 11 ++-- 2 files changed, 70 insertions(+), 64 deletions(-) diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts index 76ec977491e..7c640598e69 100644 --- a/src/compiler/checker.ts +++ b/src/compiler/checker.ts @@ -1472,7 +1472,7 @@ module ts { return appendParentTypeArgumentsAndSymbolName(symbol); } - function buildTypeDisplay(type: Type, writer: SymbolWriter, enclosingDeclaration?: Node, globalFlags?: TypeFormatFlags, typeStack?: Type[]) { + function buildTypeDisplay(type: Type, writer: SymbolWriter, enclosingDeclaration?: Node, globalFlags?: TypeFormatFlags, symbolStack?: Symbol[]) { let globalFlagsToPass = globalFlags & TypeFormatFlags.WriteOwnNameForAnyLike; return writeType(type, globalFlags); @@ -1557,49 +1557,54 @@ module ts { } function writeAnonymousType(type: ObjectType, flags: TypeFormatFlags) { - // Always use 'typeof T' for type of class, enum, and module objects - if (type.symbol && type.symbol.flags & (SymbolFlags.Class | SymbolFlags.Enum | SymbolFlags.ValueModule)) { - writeTypeofSymbol(type, flags); - } - // Use 'typeof T' for types of functions and methods that circularly reference themselves - else if (shouldWriteTypeOfFunctionSymbol()) { - writeTypeofSymbol(type, flags); - } - else if (typeStack && contains(typeStack, type)) { - // If type is an anonymous type literal in a type alias declaration, use type alias name - let typeAlias = getTypeAliasForTypeLiteral(type); - if (typeAlias) { - // The specified symbol flags need to be reinterpreted as type flags - buildSymbolDisplay(typeAlias, writer, enclosingDeclaration, SymbolFlags.Type, SymbolFormatFlags.None, flags); + let symbol = type.symbol; + if (symbol) { + // Always use 'typeof T' for type of class, enum, and module objects + if (symbol.flags & (SymbolFlags.Class | SymbolFlags.Enum | SymbolFlags.ValueModule)) { + writeTypeofSymbol(type, flags); + } + else if (shouldWriteTypeOfFunctionSymbol()) { + writeTypeofSymbol(type, flags); + } + else if (contains(symbolStack, symbol)) { + // If type is an anonymous type literal in a type alias declaration, use type alias name + let typeAlias = getTypeAliasForTypeLiteral(type); + if (typeAlias) { + // The specified symbol flags need to be reinterpreted as type flags + buildSymbolDisplay(typeAlias, writer, enclosingDeclaration, SymbolFlags.Type, SymbolFormatFlags.None, flags); + } + else { + // Recursive usage, use any + writeKeyword(writer, SyntaxKind.AnyKeyword); + } } else { - // Recursive usage, use any - writeKeyword(writer, SyntaxKind.AnyKeyword); + // Since instantiations of the same anonymous type have the same symbol, tracking symbols instead + // of types allows us to catch circular references to instantiations of the same anonymous type + if (!symbolStack) { + symbolStack = []; + } + symbolStack.push(symbol); + writeLiteralType(type, flags); + symbolStack.pop(); } } else { - if (!typeStack) { - typeStack = []; - } - typeStack.push(type); + // Anonymous types with no symbol are never circular writeLiteralType(type, flags); - typeStack.pop(); } function shouldWriteTypeOfFunctionSymbol() { - if (type.symbol) { - let isStaticMethodSymbol = !!(type.symbol.flags & SymbolFlags.Method && // typeof static method - ts.forEach(type.symbol.declarations, declaration => declaration.flags & NodeFlags.Static)); - let isNonLocalFunctionSymbol = !!(type.symbol.flags & SymbolFlags.Function) && - (type.symbol.parent || // is exported function symbol - ts.forEach(type.symbol.declarations, declaration => - declaration.parent.kind === SyntaxKind.SourceFile || declaration.parent.kind === SyntaxKind.ModuleBlock)); - - if (isStaticMethodSymbol || isNonLocalFunctionSymbol) { - // typeof is allowed only for static/non local functions - return !!(flags & TypeFormatFlags.UseTypeOfFunction) || // use typeof if format flags specify it - (typeStack && contains(typeStack, type)); // it is type of the symbol uses itself recursively - } + let isStaticMethodSymbol = !!(symbol.flags & SymbolFlags.Method && // typeof static method + forEach(symbol.declarations, declaration => declaration.flags & NodeFlags.Static)); + let isNonLocalFunctionSymbol = !!(symbol.flags & SymbolFlags.Function) && + (symbol.parent || // is exported function symbol + forEach(symbol.declarations, declaration => + declaration.parent.kind === SyntaxKind.SourceFile || declaration.parent.kind === SyntaxKind.ModuleBlock)); + if (isStaticMethodSymbol || isNonLocalFunctionSymbol) { + // typeof is allowed only for static/non local functions + return !!(flags & TypeFormatFlags.UseTypeOfFunction) || // use typeof if format flags specify it + (contains(symbolStack, symbol)); // it is type of the symbol uses itself recursively } } } @@ -1634,7 +1639,7 @@ module ts { if (flags & TypeFormatFlags.InElementType) { writePunctuation(writer, SyntaxKind.OpenParenToken); } - buildSignatureDisplay(resolved.callSignatures[0], writer, enclosingDeclaration, globalFlagsToPass | TypeFormatFlags.WriteArrowStyleSignature, typeStack); + buildSignatureDisplay(resolved.callSignatures[0], writer, enclosingDeclaration, globalFlagsToPass | TypeFormatFlags.WriteArrowStyleSignature, symbolStack); if (flags & TypeFormatFlags.InElementType) { writePunctuation(writer, SyntaxKind.CloseParenToken); } @@ -1646,7 +1651,7 @@ module ts { } writeKeyword(writer, SyntaxKind.NewKeyword); writeSpace(writer); - buildSignatureDisplay(resolved.constructSignatures[0], writer, enclosingDeclaration, globalFlagsToPass | TypeFormatFlags.WriteArrowStyleSignature, typeStack); + buildSignatureDisplay(resolved.constructSignatures[0], writer, enclosingDeclaration, globalFlagsToPass | TypeFormatFlags.WriteArrowStyleSignature, symbolStack); if (flags & TypeFormatFlags.InElementType) { writePunctuation(writer, SyntaxKind.CloseParenToken); } @@ -1658,7 +1663,7 @@ module ts { writer.writeLine(); writer.increaseIndent(); for (let signature of resolved.callSignatures) { - buildSignatureDisplay(signature, writer, enclosingDeclaration, globalFlagsToPass, typeStack); + buildSignatureDisplay(signature, writer, enclosingDeclaration, globalFlagsToPass, symbolStack); writePunctuation(writer, SyntaxKind.SemicolonToken); writer.writeLine(); } @@ -1666,7 +1671,7 @@ module ts { writeKeyword(writer, SyntaxKind.NewKeyword); writeSpace(writer); - buildSignatureDisplay(signature, writer, enclosingDeclaration, globalFlagsToPass, typeStack); + buildSignatureDisplay(signature, writer, enclosingDeclaration, globalFlagsToPass, symbolStack); writePunctuation(writer, SyntaxKind.SemicolonToken); writer.writeLine(); } @@ -1707,7 +1712,7 @@ module ts { if (p.flags & SymbolFlags.Optional) { writePunctuation(writer, SyntaxKind.QuestionToken); } - buildSignatureDisplay(signature, writer, enclosingDeclaration, globalFlagsToPass, typeStack); + buildSignatureDisplay(signature, writer, enclosingDeclaration, globalFlagsToPass, symbolStack); writePunctuation(writer, SyntaxKind.SemicolonToken); writer.writeLine(); } @@ -1736,18 +1741,18 @@ module ts { } } - function buildTypeParameterDisplay(tp: TypeParameter, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) { + function buildTypeParameterDisplay(tp: TypeParameter, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, symbolStack?: Symbol[]) { appendSymbolNameOnly(tp.symbol, writer); let constraint = getConstraintOfTypeParameter(tp); if (constraint) { writeSpace(writer); writeKeyword(writer, SyntaxKind.ExtendsKeyword); writeSpace(writer); - buildTypeDisplay(constraint, writer, enclosingDeclaration, flags, typeStack); + buildTypeDisplay(constraint, writer, enclosingDeclaration, flags, symbolStack); } } - function buildParameterDisplay(p: Symbol, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) { + function buildParameterDisplay(p: Symbol, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, symbolStack?: Symbol[]) { if (hasDotDotDotToken(p.valueDeclaration)) { writePunctuation(writer, SyntaxKind.DotDotDotToken); } @@ -1758,10 +1763,10 @@ module ts { writePunctuation(writer, SyntaxKind.ColonToken); writeSpace(writer); - buildTypeDisplay(getTypeOfSymbol(p), writer, enclosingDeclaration, flags, typeStack); + buildTypeDisplay(getTypeOfSymbol(p), writer, enclosingDeclaration, flags, symbolStack); } - function buildDisplayForTypeParametersAndDelimiters(typeParameters: TypeParameter[], writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) { + function buildDisplayForTypeParametersAndDelimiters(typeParameters: TypeParameter[], writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, symbolStack?: Symbol[]) { if (typeParameters && typeParameters.length) { writePunctuation(writer, SyntaxKind.LessThanToken); for (let i = 0; i < typeParameters.length; i++) { @@ -1769,13 +1774,13 @@ module ts { writePunctuation(writer, SyntaxKind.CommaToken); writeSpace(writer); } - buildTypeParameterDisplay(typeParameters[i], writer, enclosingDeclaration, flags, typeStack); + buildTypeParameterDisplay(typeParameters[i], writer, enclosingDeclaration, flags, symbolStack); } writePunctuation(writer, SyntaxKind.GreaterThanToken); } } - function buildDisplayForTypeArgumentsAndDelimiters(typeParameters: TypeParameter[], mapper: TypeMapper, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) { + function buildDisplayForTypeArgumentsAndDelimiters(typeParameters: TypeParameter[], mapper: TypeMapper, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, symbolStack?: Symbol[]) { if (typeParameters && typeParameters.length) { writePunctuation(writer, SyntaxKind.LessThanToken); for (let i = 0; i < typeParameters.length; i++) { @@ -1789,19 +1794,19 @@ module ts { } } - function buildDisplayForParametersAndDelimiters(parameters: Symbol[], writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) { + function buildDisplayForParametersAndDelimiters(parameters: Symbol[], writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, symbolStack?: Symbol[]) { writePunctuation(writer, SyntaxKind.OpenParenToken); for (let i = 0; i < parameters.length; i++) { if (i > 0) { writePunctuation(writer, SyntaxKind.CommaToken); writeSpace(writer); } - buildParameterDisplay(parameters[i], writer, enclosingDeclaration, flags, typeStack); + buildParameterDisplay(parameters[i], writer, enclosingDeclaration, flags, symbolStack); } writePunctuation(writer, SyntaxKind.CloseParenToken); } - function buildReturnTypeDisplay(signature: Signature, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) { + function buildReturnTypeDisplay(signature: Signature, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, symbolStack?: Symbol[]) { if (flags & TypeFormatFlags.WriteArrowStyleSignature) { writeSpace(writer); writePunctuation(writer, SyntaxKind.EqualsGreaterThanToken); @@ -1810,21 +1815,21 @@ module ts { writePunctuation(writer, SyntaxKind.ColonToken); } writeSpace(writer); - buildTypeDisplay(getReturnTypeOfSignature(signature), writer, enclosingDeclaration, flags, typeStack); + buildTypeDisplay(getReturnTypeOfSignature(signature), writer, enclosingDeclaration, flags, symbolStack); } - function buildSignatureDisplay(signature: Signature, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, typeStack?: Type[]) { + function buildSignatureDisplay(signature: Signature, writer: SymbolWriter, enclosingDeclaration?: Node, flags?: TypeFormatFlags, symbolStack?: Symbol[]) { if (signature.target && (flags & TypeFormatFlags.WriteTypeArgumentsOfSignature)) { // Instantiated signature, write type arguments instead // This is achieved by passing in the mapper separately buildDisplayForTypeArgumentsAndDelimiters(signature.target.typeParameters, signature.mapper, writer, enclosingDeclaration); } else { - buildDisplayForTypeParametersAndDelimiters(signature.typeParameters, writer, enclosingDeclaration, flags, typeStack); + buildDisplayForTypeParametersAndDelimiters(signature.typeParameters, writer, enclosingDeclaration, flags, symbolStack); } - buildDisplayForParametersAndDelimiters(signature.parameters, writer, enclosingDeclaration, flags, typeStack); - buildReturnTypeDisplay(signature, writer, enclosingDeclaration, flags, typeStack); + buildDisplayForParametersAndDelimiters(signature.parameters, writer, enclosingDeclaration, flags, symbolStack); + buildReturnTypeDisplay(signature, writer, enclosingDeclaration, flags, symbolStack); } return _displayBuilder || (_displayBuilder = { @@ -3889,7 +3894,7 @@ module ts { mapper.mappings = {}; } // Instantiate the given type using the given mapper and cache the result - let result = createObjectType(TypeFlags.Anonymous, type.symbol); + let result = createObjectType(TypeFlags.Anonymous | TypeFlags.Instantiated, type.symbol); result.properties = instantiateList(getPropertiesOfObjectType(type), mapper, instantiateSymbol); result.members = createSymbolTable(result.properties); result.callSignatures = instantiateList(getSignaturesOfType(type, SignatureKind.Call), mapper, instantiateSignature); @@ -4313,12 +4318,12 @@ module ts { // Effectively, we will generate a false positive when two types are structurally equal to at least 10 levels, but unequal at // some level beyond that. function isDeeplyNestedGeneric(type: ObjectType, stack: ObjectType[]): boolean { - if (type.flags & TypeFlags.Reference && depth >= 10) { - let target = (type).target; + if (type.flags & (TypeFlags.Reference | TypeFlags.Instantiated) && depth >= 10) { + let symbol = type.symbol; let count = 0; for (let i = 0; i < depth; i++) { let t = stack[i]; - if (t.flags & TypeFlags.Reference && (t).target === target) { + if (t.flags & (TypeFlags.Reference | TypeFlags.Instantiated) && t.symbol === symbol) { count++; if (count >= 10) return true; } diff --git a/src/compiler/types.ts b/src/compiler/types.ts index 3d52d096b03..a6ab19d4296 100644 --- a/src/compiler/types.ts +++ b/src/compiler/types.ts @@ -1582,14 +1582,15 @@ module ts { Tuple = 0x00002000, // Tuple Union = 0x00004000, // Union Anonymous = 0x00008000, // Anonymous + Instantiated = 0x00010000, // Instantiated anonymous type /* @internal */ - FromSignature = 0x00010000, // Created for signature assignment check - ObjectLiteral = 0x00020000, // Originates in an object literal + FromSignature = 0x00020000, // Created for signature assignment check + ObjectLiteral = 0x00040000, // Originates in an object literal /* @internal */ - ContainsUndefinedOrNull = 0x00040000, // Type is or contains Undefined or Null type + ContainsUndefinedOrNull = 0x00080000, // Type is or contains Undefined or Null type /* @internal */ - ContainsObjectLiteral = 0x00080000, // Type is or contains object literal type - ESSymbol = 0x00100000, // Type of symbol primitive introduced in ES6 + ContainsObjectLiteral = 0x00100000, // Type is or contains object literal type + ESSymbol = 0x00200000, // Type of symbol primitive introduced in ES6 /* @internal */ Intrinsic = Any | String | Number | Boolean | ESSymbol | Void | Undefined | Null, From 46e0ba82cec8e97e1e0be137e94d1d2fcef31381 Mon Sep 17 00:00:00 2001 From: Anders Hejlsberg Date: Sat, 30 May 2015 17:25:44 -0700 Subject: [PATCH 2/4] Remove old (and insufficient) instantiation caching --- src/compiler/checker.ts | 14 +------------- src/compiler/types.ts | 1 - 2 files changed, 1 insertion(+), 14 deletions(-) diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts index 7c640598e69..c180d8425f2 100644 --- a/src/compiler/checker.ts +++ b/src/compiler/checker.ts @@ -3882,18 +3882,7 @@ module ts { } function instantiateAnonymousType(type: ObjectType, mapper: TypeMapper): ObjectType { - // If this type has already been instantiated using this mapper, returned the cached result. This guards against - // infinite instantiations of cyclic types, e.g. "var x: { a: T, b: typeof x };" - if (mapper.mappings) { - let cached = mapper.mappings[type.id]; - if (cached) { - return cached; - } - } - else { - mapper.mappings = {}; - } - // Instantiate the given type using the given mapper and cache the result + // Mark the anonymous type as instantiated such that our infinite instantiation detection logic can recognize it let result = createObjectType(TypeFlags.Anonymous | TypeFlags.Instantiated, type.symbol); result.properties = instantiateList(getPropertiesOfObjectType(type), mapper, instantiateSymbol); result.members = createSymbolTable(result.properties); @@ -3903,7 +3892,6 @@ module ts { let numberIndexType = getIndexTypeOfType(type, IndexKind.Number); if (stringIndexType) result.stringIndexType = instantiateType(stringIndexType, mapper); if (numberIndexType) result.numberIndexType = instantiateType(numberIndexType, mapper); - mapper.mappings[type.id] = result; return result; } diff --git a/src/compiler/types.ts b/src/compiler/types.ts index a6ab19d4296..2d1175df080 100644 --- a/src/compiler/types.ts +++ b/src/compiler/types.ts @@ -1730,7 +1730,6 @@ module ts { /* @internal */ export interface TypeMapper { (t: TypeParameter): Type; - mappings?: Map; // Type mapping cache } /* @internal */ From e336e3ad0aa6e983d380dcd9bbd107b157a5bfba Mon Sep 17 00:00:00 2001 From: Anders Hejlsberg Date: Sat, 30 May 2015 18:09:13 -0700 Subject: [PATCH 3/4] Adding regression test --- .../cyclicGenericTypeInstantiation.js | 37 ++++++++++++ .../cyclicGenericTypeInstantiation.symbols | 55 +++++++++++++++++ .../cyclicGenericTypeInstantiation.types | 60 +++++++++++++++++++ .../cyclicGenericTypeInstantiation.ts | 20 +++++++ 4 files changed, 172 insertions(+) create mode 100644 tests/baselines/reference/cyclicGenericTypeInstantiation.js create mode 100644 tests/baselines/reference/cyclicGenericTypeInstantiation.symbols create mode 100644 tests/baselines/reference/cyclicGenericTypeInstantiation.types create mode 100644 tests/cases/compiler/cyclicGenericTypeInstantiation.ts diff --git a/tests/baselines/reference/cyclicGenericTypeInstantiation.js b/tests/baselines/reference/cyclicGenericTypeInstantiation.js new file mode 100644 index 00000000000..10f52e10d89 --- /dev/null +++ b/tests/baselines/reference/cyclicGenericTypeInstantiation.js @@ -0,0 +1,37 @@ +//// [cyclicGenericTypeInstantiation.ts] +function foo() { + var z = foo(); + var y: { + y2: typeof z + }; + return y; +} + + +function bar() { + var z = bar(); + var y: { + y2: typeof z; + } + return y; +} + +var a = foo(); +var b = bar(); +a = b; + + +//// [cyclicGenericTypeInstantiation.js] +function foo() { + var z = foo(); + var y; + return y; +} +function bar() { + var z = bar(); + var y; + return y; +} +var a = foo(); +var b = bar(); +a = b; diff --git a/tests/baselines/reference/cyclicGenericTypeInstantiation.symbols b/tests/baselines/reference/cyclicGenericTypeInstantiation.symbols new file mode 100644 index 00000000000..a6566b86839 --- /dev/null +++ b/tests/baselines/reference/cyclicGenericTypeInstantiation.symbols @@ -0,0 +1,55 @@ +=== tests/cases/compiler/cyclicGenericTypeInstantiation.ts === +function foo() { +>foo : Symbol(foo, Decl(cyclicGenericTypeInstantiation.ts, 0, 0)) +>T : Symbol(T, Decl(cyclicGenericTypeInstantiation.ts, 0, 13)) + + var z = foo(); +>z : Symbol(z, Decl(cyclicGenericTypeInstantiation.ts, 1, 7)) +>foo : Symbol(foo, Decl(cyclicGenericTypeInstantiation.ts, 0, 0)) +>y : Symbol(y, Decl(cyclicGenericTypeInstantiation.ts, 2, 7)) + + var y: { +>y : Symbol(y, Decl(cyclicGenericTypeInstantiation.ts, 2, 7)) + + y2: typeof z +>y2 : Symbol(y2, Decl(cyclicGenericTypeInstantiation.ts, 2, 12)) +>z : Symbol(z, Decl(cyclicGenericTypeInstantiation.ts, 1, 7)) + + }; + return y; +>y : Symbol(y, Decl(cyclicGenericTypeInstantiation.ts, 2, 7)) +} + + +function bar() { +>bar : Symbol(bar, Decl(cyclicGenericTypeInstantiation.ts, 6, 1)) +>T : Symbol(T, Decl(cyclicGenericTypeInstantiation.ts, 9, 13)) + + var z = bar(); +>z : Symbol(z, Decl(cyclicGenericTypeInstantiation.ts, 10, 7)) +>bar : Symbol(bar, Decl(cyclicGenericTypeInstantiation.ts, 6, 1)) +>y : Symbol(y, Decl(cyclicGenericTypeInstantiation.ts, 11, 7)) + + var y: { +>y : Symbol(y, Decl(cyclicGenericTypeInstantiation.ts, 11, 7)) + + y2: typeof z; +>y2 : Symbol(y2, Decl(cyclicGenericTypeInstantiation.ts, 11, 12)) +>z : Symbol(z, Decl(cyclicGenericTypeInstantiation.ts, 10, 7)) + } + return y; +>y : Symbol(y, Decl(cyclicGenericTypeInstantiation.ts, 11, 7)) +} + +var a = foo(); +>a : Symbol(a, Decl(cyclicGenericTypeInstantiation.ts, 17, 3)) +>foo : Symbol(foo, Decl(cyclicGenericTypeInstantiation.ts, 0, 0)) + +var b = bar(); +>b : Symbol(b, Decl(cyclicGenericTypeInstantiation.ts, 18, 3)) +>bar : Symbol(bar, Decl(cyclicGenericTypeInstantiation.ts, 6, 1)) + +a = b; +>a : Symbol(a, Decl(cyclicGenericTypeInstantiation.ts, 17, 3)) +>b : Symbol(b, Decl(cyclicGenericTypeInstantiation.ts, 18, 3)) + diff --git a/tests/baselines/reference/cyclicGenericTypeInstantiation.types b/tests/baselines/reference/cyclicGenericTypeInstantiation.types new file mode 100644 index 00000000000..69b0955b22f --- /dev/null +++ b/tests/baselines/reference/cyclicGenericTypeInstantiation.types @@ -0,0 +1,60 @@ +=== tests/cases/compiler/cyclicGenericTypeInstantiation.ts === +function foo() { +>foo : () => { y2: any; } +>T : T + + var z = foo(); +>z : { y2: any; } +>foo() : { y2: any; } +>foo : () => { y2: any; } +>y : { y2: any; } + + var y: { +>y : { y2: any; } + + y2: typeof z +>y2 : { y2: any; } +>z : { y2: any; } + + }; + return y; +>y : { y2: any; } +} + + +function bar() { +>bar : () => { y2: any; } +>T : T + + var z = bar(); +>z : { y2: any; } +>bar() : { y2: any; } +>bar : () => { y2: any; } +>y : { y2: any; } + + var y: { +>y : { y2: any; } + + y2: typeof z; +>y2 : { y2: any; } +>z : { y2: any; } + } + return y; +>y : { y2: any; } +} + +var a = foo(); +>a : { y2: any; } +>foo() : { y2: any; } +>foo : () => { y2: any; } + +var b = bar(); +>b : { y2: any; } +>bar() : { y2: any; } +>bar : () => { y2: any; } + +a = b; +>a = b : { y2: any; } +>a : { y2: any; } +>b : { y2: any; } + diff --git a/tests/cases/compiler/cyclicGenericTypeInstantiation.ts b/tests/cases/compiler/cyclicGenericTypeInstantiation.ts new file mode 100644 index 00000000000..070cc44a63a --- /dev/null +++ b/tests/cases/compiler/cyclicGenericTypeInstantiation.ts @@ -0,0 +1,20 @@ +function foo() { + var z = foo(); + var y: { + y2: typeof z + }; + return y; +} + + +function bar() { + var z = bar(); + var y: { + y2: typeof z; + } + return y; +} + +var a = foo(); +var b = bar(); +a = b; From dd8f3c41ad9eb06ddfd40b5d76a2cd4d2155b1db Mon Sep 17 00:00:00 2001 From: Anders Hejlsberg Date: Wed, 3 Jun 2015 14:08:37 -0700 Subject: [PATCH 4/4] Addressing CR feedback --- src/compiler/checker.ts | 1 + 1 file changed, 1 insertion(+) diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts index c180d8425f2..45a40135be8 100644 --- a/src/compiler/checker.ts +++ b/src/compiler/checker.ts @@ -4306,6 +4306,7 @@ module ts { // Effectively, we will generate a false positive when two types are structurally equal to at least 10 levels, but unequal at // some level beyond that. function isDeeplyNestedGeneric(type: ObjectType, stack: ObjectType[]): boolean { + // We track type references (created by createTypeReference) and instantiated types (created by instantiateType) if (type.flags & (TypeFlags.Reference | TypeFlags.Instantiated) && depth >= 10) { let symbol = type.symbol; let count = 0;