From 251723826962cc3fa3cc2d766c17dc197099cce3 Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Thu, 2 Jun 2016 06:32:14 -0700
Subject: [PATCH 1/3] Add non-widening forms of null and undefined
---
src/compiler/checker.ts | 37 ++++++++++++++++++++-----------------
src/compiler/types.ts | 6 +++---
2 files changed, 23 insertions(+), 20 deletions(-)
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 06ef246340252..6166234dcf4d3 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -110,16 +110,17 @@ namespace ts {
const unknownSymbol = createSymbol(SymbolFlags.Property | SymbolFlags.Transient, "unknown");
const resolvingSymbol = createSymbol(SymbolFlags.Transient, "__resolving__");
- const nullableWideningFlags = strictNullChecks ? 0 : TypeFlags.ContainsUndefinedOrNull;
const anyType = createIntrinsicType(TypeFlags.Any, "any");
const stringType = createIntrinsicType(TypeFlags.String, "string");
const numberType = createIntrinsicType(TypeFlags.Number, "number");
const booleanType = createIntrinsicType(TypeFlags.Boolean, "boolean");
const esSymbolType = createIntrinsicType(TypeFlags.ESSymbol, "symbol");
const voidType = createIntrinsicType(TypeFlags.Void, "void");
- const undefinedType = createIntrinsicType(TypeFlags.Undefined | nullableWideningFlags, "undefined");
- const nullType = createIntrinsicType(TypeFlags.Null | nullableWideningFlags, "null");
- const emptyArrayElementType = createIntrinsicType(TypeFlags.Undefined | TypeFlags.ContainsUndefinedOrNull, "undefined");
+ const undefinedType = createIntrinsicType(TypeFlags.Undefined, "undefined");
+ const undefinedWideningType = strictNullChecks ? undefinedType : createIntrinsicType(TypeFlags.Undefined | TypeFlags.ContainsWideningType, "undefined");
+ const nullType = createIntrinsicType(TypeFlags.Null, "null");
+ const nullWideningType = strictNullChecks ? nullType : createIntrinsicType(TypeFlags.Null | TypeFlags.ContainsWideningType, "null");
+ const emptyArrayElementType = createIntrinsicType(TypeFlags.Undefined | TypeFlags.ContainsWideningType, "undefined");
const unknownType = createIntrinsicType(TypeFlags.Any, "unknown");
const neverType = createIntrinsicType(TypeFlags.Never, "never");
@@ -3405,7 +3406,7 @@ namespace ts {
error(type.symbol.valueDeclaration, Diagnostics._0_is_referenced_directly_or_indirectly_in_its_own_base_expression, symbolToString(type.symbol));
return type.resolvedBaseConstructorType = unknownType;
}
- if (baseConstructorType !== unknownType && baseConstructorType !== nullType && !isConstructorType(baseConstructorType)) {
+ if (baseConstructorType !== unknownType && baseConstructorType !== nullWideningType && !isConstructorType(baseConstructorType)) {
error(baseTypeNode.expression, Diagnostics.Type_0_is_not_a_constructor_function_type, typeToString(baseConstructorType));
return type.resolvedBaseConstructorType = unknownType;
}
@@ -5011,6 +5012,7 @@ namespace ts {
containsAny?: boolean;
containsUndefined?: boolean;
containsNull?: boolean;
+ containsNonWideningType?: boolean;
}
function addTypeToSet(typeSet: TypeSet, type: Type, typeSetKind: TypeFlags) {
@@ -5021,6 +5023,7 @@ namespace ts {
if (type.flags & TypeFlags.Any) typeSet.containsAny = true;
if (type.flags & TypeFlags.Undefined) typeSet.containsUndefined = true;
if (type.flags & TypeFlags.Null) typeSet.containsNull = true;
+ if (!(type.flags & TypeFlags.ContainsWideningType)) typeSet.containsNonWideningType = true;
}
else if (type !== neverType && !contains(typeSet, type)) {
typeSet.push(type);
@@ -5081,8 +5084,8 @@ namespace ts {
removeSubtypes(typeSet);
}
if (typeSet.length === 0) {
- return typeSet.containsNull ? nullType :
- typeSet.containsUndefined ? undefinedType :
+ return typeSet.containsNull ? typeSet.containsNonWideningType ? nullType : nullWideningType :
+ typeSet.containsUndefined ? typeSet.containsNonWideningType ? undefinedType : undefinedWideningType :
neverType;
}
else if (typeSet.length === 1) {
@@ -5882,7 +5885,7 @@ namespace ts {
if (!(target.flags & TypeFlags.Never)) {
if (target.flags & TypeFlags.Any || source.flags & TypeFlags.Never) return Ternary.True;
if (source.flags & TypeFlags.Undefined) {
- if (!strictNullChecks || target.flags & (TypeFlags.Undefined | TypeFlags.Void) || source === emptyArrayElementType) return Ternary.True;
+ if (!strictNullChecks || target.flags & (TypeFlags.Undefined | TypeFlags.Void)) return Ternary.True;
}
if (source.flags & TypeFlags.Null) {
if (!strictNullChecks || target.flags & TypeFlags.Null) return Ternary.True;
@@ -6972,7 +6975,7 @@ namespace ts {
if (type.flags & TypeFlags.ObjectLiteral) {
for (const p of getPropertiesOfObjectType(type)) {
const t = getTypeOfSymbol(p);
- if (t.flags & TypeFlags.ContainsUndefinedOrNull) {
+ if (t.flags & TypeFlags.ContainsWideningType) {
if (!reportWideningErrorsInType(t)) {
error(p.valueDeclaration, Diagnostics.Object_literal_s_property_0_implicitly_has_an_1_type, p.name, typeToString(getWidenedType(t)));
}
@@ -7019,7 +7022,7 @@ namespace ts {
}
function reportErrorsFromWidening(declaration: Declaration, type: Type) {
- if (produceDiagnostics && compilerOptions.noImplicitAny && type.flags & TypeFlags.ContainsUndefinedOrNull) {
+ if (produceDiagnostics && compilerOptions.noImplicitAny && type.flags & TypeFlags.ContainsWideningType) {
// Report implicit any error within type if possible, otherwise report error on declaration
if (!reportWideningErrorsInType(type)) {
reportImplicitAnyError(declaration, type);
@@ -8311,7 +8314,7 @@ namespace ts {
const classInstanceType = <InterfaceType>getDeclaredTypeOfSymbol(classSymbol);
const baseConstructorType = getBaseConstructorTypeOfClass(classInstanceType);
- return baseConstructorType === nullType;
+ return baseConstructorType === nullWideningType;
}
function checkThisExpression(node: Node): Type {
@@ -9202,7 +9205,7 @@ namespace ts {
}
}
}
- return createArrayType(elementTypes.length ? getUnionType(elementTypes) : emptyArrayElementType);
+ return createArrayType(elementTypes.length ? getUnionType(elementTypes) : strictNullChecks ? neverType : undefinedWideningType);
}
function isNumericName(name: DeclarationName): boolean {
@@ -12002,7 +12005,7 @@ namespace ts {
function checkVoidExpression(node: VoidExpression): Type {
checkExpression(node.expression);
- return undefinedType;
+ return undefinedWideningType;
}
function checkAwaitExpression(node: AwaitExpression): Type {
@@ -12409,7 +12412,7 @@ namespace ts {
case SyntaxKind.InKeyword:
return checkInExpression(left, right, leftType, rightType);
case SyntaxKind.AmpersandAmpersandToken:
- return addNullableKind(rightType, getNullableKind(leftType));
+ return strictNullChecks ? addNullableKind(rightType, getNullableKind(leftType)) : rightType;
case SyntaxKind.BarBarToken:
return getUnionType([getNonNullableType(leftType), rightType]);
case SyntaxKind.EqualsToken:
@@ -12676,7 +12679,7 @@ namespace ts {
case SyntaxKind.SuperKeyword:
return checkSuperExpression(node);
case SyntaxKind.NullKeyword:
- return nullType;
+ return nullWideningType;
case SyntaxKind.TrueKeyword:
case SyntaxKind.FalseKeyword:
return booleanType;
@@ -12734,7 +12737,7 @@ namespace ts {
case SyntaxKind.SpreadElementExpression:
return checkSpreadElementExpression(<SpreadElementExpression>node, contextualMapper);
case SyntaxKind.OmittedExpression:
- return undefinedType;
+ return undefinedWideningType;
case SyntaxKind.YieldExpression:
return checkYieldExpression(<YieldExpression>node);
case SyntaxKind.JsxExpression:
@@ -17648,7 +17651,7 @@ namespace ts {
// Setup global builtins
addToSymbolTable(globals, builtinGlobals, Diagnostics.Declaration_name_conflicts_with_built_in_global_identifier_0);
- getSymbolLinks(undefinedSymbol).type = undefinedType;
+ getSymbolLinks(undefinedSymbol).type = undefinedWideningType;
getSymbolLinks(argumentsSymbol).type = getGlobalType("IArguments");
getSymbolLinks(unknownSymbol).type = unknownType;
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index c7e14a1003108..4c0e7a036dbf4 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -2197,7 +2197,7 @@ namespace ts {
/* @internal */
FreshObjectLiteral = 0x00100000, // Fresh object literal type
/* @internal */
- ContainsUndefinedOrNull = 0x00200000, // Type is or contains undefined or null type
+ ContainsWideningType = 0x00200000, // Type is or contains undefined or null widening type
/* @internal */
ContainsObjectLiteral = 0x00400000, // Type is or contains object literal type
/* @internal */
@@ -2220,9 +2220,9 @@ namespace ts {
StructuredType = ObjectType | Union | Intersection,
Narrowable = Any | ObjectType | Union | TypeParameter,
/* @internal */
- RequiresWidening = ContainsUndefinedOrNull | ContainsObjectLiteral,
+ RequiresWidening = ContainsWideningType | ContainsObjectLiteral,
/* @internal */
- PropagatingFlags = ContainsUndefinedOrNull | ContainsObjectLiteral | ContainsAnyFunctionType
+ PropagatingFlags = ContainsWideningType | ContainsObjectLiteral | ContainsAnyFunctionType
}
export type DestructuringPattern = BindingPattern | ObjectLiteralExpression | ArrayLiteralExpression;
From 20bab14224bf9f7a7228f416a61807b1f7f73e4a Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Thu, 2 Jun 2016 09:39:47 -0700
Subject: [PATCH 2/3] Add tests
---
.../reference/arrayLiteralWidened.js | 15 ++++
.../reference/arrayLiteralWidened.symbols | 38 +++++++--
.../reference/arrayLiteralWidened.types | 29 +++++++
.../reference/initializersWidened.js | 42 +++++++++-
.../reference/initializersWidened.symbols | 55 ++++++++++++-
.../reference/initializersWidened.types | 77 ++++++++++++++++++-
.../logicalAndOperatorWithEveryType.types | 2 +-
.../reference/objectLiteralWidened.js | 40 +++++++++-
.../reference/objectLiteralWidened.symbols | 53 +++++++++++--
.../reference/objectLiteralWidened.types | 54 ++++++++++++-
.../reference/strictNullChecksNoWidening.js | 31 ++++++++
.../strictNullChecksNoWidening.symbols | 48 ++++++++++++
.../strictNullChecksNoWidening.types | 67 ++++++++++++++++
.../widenedTypes/arrayLiteralWidened.ts | 9 +++
.../widenedTypes/initializersWidened.ts | 24 +++++-
.../widenedTypes/objectLiteralWidened.ts | 22 +++++-
.../strictNullChecksNoWidening.ts | 17 ++++
17 files changed, 584 insertions(+), 39 deletions(-)
create mode 100644 tests/baselines/reference/strictNullChecksNoWidening.js
create mode 100644 tests/baselines/reference/strictNullChecksNoWidening.symbols
create mode 100644 tests/baselines/reference/strictNullChecksNoWidening.types
create mode 100644 tests/cases/conformance/types/typeRelationships/widenedTypes/strictNullChecksNoWidening.ts
diff --git a/tests/baselines/reference/arrayLiteralWidened.js b/tests/baselines/reference/arrayLiteralWidened.js
index a250c47849d57..5b7346b87381b 100644
--- a/tests/baselines/reference/arrayLiteralWidened.js
+++ b/tests/baselines/reference/arrayLiteralWidened.js
@@ -2,6 +2,7 @@
// array literals are widened upon assignment according to their element type
var a = []; // any[]
+var a = [,,];
var a = [null, null];
var a = [undefined, undefined];
@@ -12,11 +13,20 @@ var b = [[undefined, undefined]];
var c = [[[]]]; // any[][][]
var c = [[[null]],[undefined]]
+
+// no widening when one or more elements are non-widening
+
+var x: undefined = undefined;
+
+var d = [x];
+var d = [, x];
+var d = [undefined, x];
//// [arrayLiteralWidened.js]
// array literals are widened upon assignment according to their element type
var a = []; // any[]
+var a = [, ,];
var a = [null, null];
var a = [undefined, undefined];
var b = [[], [null, null]]; // any[][]
@@ -24,3 +34,8 @@ var b = [[], []];
var b = [[undefined, undefined]];
var c = [[[]]]; // any[][][]
var c = [[[null]], [undefined]];
+// no widening when one or more elements are non-widening
+var x = undefined;
+var d = [x];
+var d = [, x];
+var d = [undefined, x];
diff --git a/tests/baselines/reference/arrayLiteralWidened.symbols b/tests/baselines/reference/arrayLiteralWidened.symbols
index ba058aeded114..48137812a5dfc 100644
--- a/tests/baselines/reference/arrayLiteralWidened.symbols
+++ b/tests/baselines/reference/arrayLiteralWidened.symbols
@@ -2,31 +2,53 @@
// array literals are widened upon assignment according to their element type
var a = []; // any[]
->a : Symbol(a, Decl(arrayLiteralWidened.ts, 2, 3), Decl(arrayLiteralWidened.ts, 4, 3), Decl(arrayLiteralWidened.ts, 5, 3))
+>a : Symbol(a, Decl(arrayLiteralWidened.ts, 2, 3), Decl(arrayLiteralWidened.ts, 3, 3), Decl(arrayLiteralWidened.ts, 5, 3), Decl(arrayLiteralWidened.ts, 6, 3))
+
+var a = [,,];
+>a : Symbol(a, Decl(arrayLiteralWidened.ts, 2, 3), Decl(arrayLiteralWidened.ts, 3, 3), Decl(arrayLiteralWidened.ts, 5, 3), Decl(arrayLiteralWidened.ts, 6, 3))
var a = [null, null];
->a : Symbol(a, Decl(arrayLiteralWidened.ts, 2, 3), Decl(arrayLiteralWidened.ts, 4, 3), Decl(arrayLiteralWidened.ts, 5, 3))
+>a : Symbol(a, Decl(arrayLiteralWidened.ts, 2, 3), Decl(arrayLiteralWidened.ts, 3, 3), Decl(arrayLiteralWidened.ts, 5, 3), Decl(arrayLiteralWidened.ts, 6, 3))
var a = [undefined, undefined];
->a : Symbol(a, Decl(arrayLiteralWidened.ts, 2, 3), Decl(arrayLiteralWidened.ts, 4, 3), Decl(arrayLiteralWidened.ts, 5, 3))
+>a : Symbol(a, Decl(arrayLiteralWidened.ts, 2, 3), Decl(arrayLiteralWidened.ts, 3, 3), Decl(arrayLiteralWidened.ts, 5, 3), Decl(arrayLiteralWidened.ts, 6, 3))
>undefined : Symbol(undefined)
>undefined : Symbol(undefined)
var b = [[], [null, null]]; // any[][]
->b : Symbol(b, Decl(arrayLiteralWidened.ts, 7, 3), Decl(arrayLiteralWidened.ts, 8, 3), Decl(arrayLiteralWidened.ts, 9, 3))
+>b : Symbol(b, Decl(arrayLiteralWidened.ts, 8, 3), Decl(arrayLiteralWidened.ts, 9, 3), Decl(arrayLiteralWidened.ts, 10, 3))
var b = [[], []];
->b : Symbol(b, Decl(arrayLiteralWidened.ts, 7, 3), Decl(arrayLiteralWidened.ts, 8, 3), Decl(arrayLiteralWidened.ts, 9, 3))
+>b : Symbol(b, Decl(arrayLiteralWidened.ts, 8, 3), Decl(arrayLiteralWidened.ts, 9, 3), Decl(arrayLiteralWidened.ts, 10, 3))
var b = [[undefined, undefined]];
->b : Symbol(b, Decl(arrayLiteralWidened.ts, 7, 3), Decl(arrayLiteralWidened.ts, 8, 3), Decl(arrayLiteralWidened.ts, 9, 3))
+>b : Symbol(b, Decl(arrayLiteralWidened.ts, 8, 3), Decl(arrayLiteralWidened.ts, 9, 3), Decl(arrayLiteralWidened.ts, 10, 3))
>undefined : Symbol(undefined)
>undefined : Symbol(undefined)
var c = [[[]]]; // any[][][]
->c : Symbol(c, Decl(arrayLiteralWidened.ts, 11, 3), Decl(arrayLiteralWidened.ts, 12, 3))
+>c : Symbol(c, Decl(arrayLiteralWidened.ts, 12, 3), Decl(arrayLiteralWidened.ts, 13, 3))
var c = [[[null]],[undefined]]
->c : Symbol(c, Decl(arrayLiteralWidened.ts, 11, 3), Decl(arrayLiteralWidened.ts, 12, 3))
+>c : Symbol(c, Decl(arrayLiteralWidened.ts, 12, 3), Decl(arrayLiteralWidened.ts, 13, 3))
+>undefined : Symbol(undefined)
+
+// no widening when one or more elements are non-widening
+
+var x: undefined = undefined;
+>x : Symbol(x, Decl(arrayLiteralWidened.ts, 17, 3))
+>undefined : Symbol(undefined)
+
+var d = [x];
+>d : Symbol(d, Decl(arrayLiteralWidened.ts, 19, 3), Decl(arrayLiteralWidened.ts, 20, 3), Decl(arrayLiteralWidened.ts, 21, 3))
+>x : Symbol(x, Decl(arrayLiteralWidened.ts, 17, 3))
+
+var d = [, x];
+>d : Symbol(d, Decl(arrayLiteralWidened.ts, 19, 3), Decl(arrayLiteralWidened.ts, 20, 3), Decl(arrayLiteralWidened.ts, 21, 3))
+>x : Symbol(x, Decl(arrayLiteralWidened.ts, 17, 3))
+
+var d = [undefined, x];
+>d : Symbol(d, Decl(arrayLiteralWidened.ts, 19, 3), Decl(arrayLiteralWidened.ts, 20, 3), Decl(arrayLiteralWidened.ts, 21, 3))
>undefined : Symbol(undefined)
+>x : Symbol(x, Decl(arrayLiteralWidened.ts, 17, 3))
diff --git a/tests/baselines/reference/arrayLiteralWidened.types b/tests/baselines/reference/arrayLiteralWidened.types
index 83db7046eed4a..6237cd79a7edb 100644
--- a/tests/baselines/reference/arrayLiteralWidened.types
+++ b/tests/baselines/reference/arrayLiteralWidened.types
@@ -5,6 +5,12 @@ var a = []; // any[]
>a : any[]
>[] : undefined[]
+var a = [,,];
+>a : any[]
+>[,,] : undefined[]
+> : undefined
+> : undefined
+
var a = [null, null];
>a : any[]
>[null, null] : null[]
@@ -53,3 +59,26 @@ var c = [[[null]],[undefined]]
>[undefined] : undefined[]
>undefined : undefined
+// no widening when one or more elements are non-widening
+
+var x: undefined = undefined;
+>x : undefined
+>undefined : undefined
+
+var d = [x];
+>d : undefined[]
+>[x] : undefined[]
+>x : undefined
+
+var d = [, x];
+>d : undefined[]
+>[, x] : undefined[]
+> : undefined
+>x : undefined
+
+var d = [undefined, x];
+>d : undefined[]
+>[undefined, x] : undefined[]
+>undefined : undefined
+>x : undefined
+
diff --git a/tests/baselines/reference/initializersWidened.js b/tests/baselines/reference/initializersWidened.js
index fce0750a600c8..3954735ee6ede 100644
--- a/tests/baselines/reference/initializersWidened.js
+++ b/tests/baselines/reference/initializersWidened.js
@@ -1,10 +1,44 @@
//// [initializersWidened.ts]
// these are widened to any at the point of assignment
-var x = null;
-var y = undefined;
+var x1 = null;
+var y1 = undefined;
+var z1 = void 0;
+
+// these are not widened
+
+var x2: null;
+var y2: undefined;
+
+var x3: null = null;
+var y3: undefined = undefined;
+var z3: undefined = void 0;
+
+// widen only when all constituents of union are widening
+
+var x4 = null || null;
+var y4 = undefined || undefined;
+var z4 = void 0 || void 0;
+
+var x5 = null || x2;
+var y5 = undefined || y2;
+var z5 = void 0 || y2;
//// [initializersWidened.js]
// these are widened to any at the point of assignment
-var x = null;
-var y = undefined;
+var x1 = null;
+var y1 = undefined;
+var z1 = void 0;
+// these are not widened
+var x2;
+var y2;
+var x3 = null;
+var y3 = undefined;
+var z3 = void 0;
+// widen only when all constituents of union are widening
+var x4 = null || null;
+var y4 = undefined || undefined;
+var z4 = void 0 || void 0;
+var x5 = null || x2;
+var y5 = undefined || y2;
+var z5 = void 0 || y2;
diff --git a/tests/baselines/reference/initializersWidened.symbols b/tests/baselines/reference/initializersWidened.symbols
index 625c066a0587e..252a248bec867 100644
--- a/tests/baselines/reference/initializersWidened.symbols
+++ b/tests/baselines/reference/initializersWidened.symbols
@@ -1,10 +1,57 @@
=== tests/cases/conformance/types/typeRelationships/widenedTypes/initializersWidened.ts ===
// these are widened to any at the point of assignment
-var x = null;
->x : Symbol(x, Decl(initializersWidened.ts, 2, 3))
+var x1 = null;
+>x1 : Symbol(x1, Decl(initializersWidened.ts, 2, 3))
-var y = undefined;
->y : Symbol(y, Decl(initializersWidened.ts, 3, 3))
+var y1 = undefined;
+>y1 : Symbol(y1, Decl(initializersWidened.ts, 3, 3))
>undefined : Symbol(undefined)
+var z1 = void 0;
+>z1 : Symbol(z1, Decl(initializersWidened.ts, 4, 3))
+
+// these are not widened
+
+var x2: null;
+>x2 : Symbol(x2, Decl(initializersWidened.ts, 8, 3))
+
+var y2: undefined;
+>y2 : Symbol(y2, Decl(initializersWidened.ts, 9, 3))
+
+var x3: null = null;
+>x3 : Symbol(x3, Decl(initializersWidened.ts, 11, 3))
+
+var y3: undefined = undefined;
+>y3 : Symbol(y3, Decl(initializersWidened.ts, 12, 3))
+>undefined : Symbol(undefined)
+
+var z3: undefined = void 0;
+>z3 : Symbol(z3, Decl(initializersWidened.ts, 13, 3))
+
+// widen only when all constituents of union are widening
+
+var x4 = null || null;
+>x4 : Symbol(x4, Decl(initializersWidened.ts, 17, 3))
+
+var y4 = undefined || undefined;
+>y4 : Symbol(y4, Decl(initializersWidened.ts, 18, 3))
+>undefined : Symbol(undefined)
+>undefined : Symbol(undefined)
+
+var z4 = void 0 || void 0;
+>z4 : Symbol(z4, Decl(initializersWidened.ts, 19, 3))
+
+var x5 = null || x2;
+>x5 : Symbol(x5, Decl(initializersWidened.ts, 21, 3))
+>x2 : Symbol(x2, Decl(initializersWidened.ts, 8, 3))
+
+var y5 = undefined || y2;
+>y5 : Symbol(y5, Decl(initializersWidened.ts, 22, 3))
+>undefined : Symbol(undefined)
+>y2 : Symbol(y2, Decl(initializersWidened.ts, 9, 3))
+
+var z5 = void 0 || y2;
+>z5 : Symbol(z5, Decl(initializersWidened.ts, 23, 3))
+>y2 : Symbol(y2, Decl(initializersWidened.ts, 9, 3))
+
diff --git a/tests/baselines/reference/initializersWidened.types b/tests/baselines/reference/initializersWidened.types
index 157055892460a..766f859029af9 100644
--- a/tests/baselines/reference/initializersWidened.types
+++ b/tests/baselines/reference/initializersWidened.types
@@ -1,11 +1,80 @@
=== tests/cases/conformance/types/typeRelationships/widenedTypes/initializersWidened.ts ===
// these are widened to any at the point of assignment
-var x = null;
->x : any
+var x1 = null;
+>x1 : any
>null : null
-var y = undefined;
->y : any
+var y1 = undefined;
+>y1 : any
>undefined : undefined
+var z1 = void 0;
+>z1 : any
+>void 0 : undefined
+>0 : number
+
+// these are not widened
+
+var x2: null;
+>x2 : null
+>null : null
+
+var y2: undefined;
+>y2 : undefined
+
+var x3: null = null;
+>x3 : null
+>null : null
+>null : null
+
+var y3: undefined = undefined;
+>y3 : undefined
+>undefined : undefined
+
+var z3: undefined = void 0;
+>z3 : undefined
+>void 0 : undefined
+>0 : number
+
+// widen only when all constituents of union are widening
+
+var x4 = null || null;
+>x4 : any
+>null || null : null
+>null : null
+>null : null
+
+var y4 = undefined || undefined;
+>y4 : any
+>undefined || undefined : undefined
+>undefined : undefined
+>undefined : undefined
+
+var z4 = void 0 || void 0;
+>z4 : any
+>void 0 || void 0 : undefined
+>void 0 : undefined
+>0 : number
+>void 0 : undefined
+>0 : number
+
+var x5 = null || x2;
+>x5 : null
+>null || x2 : null
+>null : null
+>x2 : null
+
+var y5 = undefined || y2;
+>y5 : undefined
+>undefined || y2 : undefined
+>undefined : undefined
+>y2 : undefined
+
+var z5 = void 0 || y2;
+>z5 : undefined
+>void 0 || y2 : undefined
+>void 0 : undefined
+>0 : number
+>y2 : undefined
+
diff --git a/tests/baselines/reference/logicalAndOperatorWithEveryType.types b/tests/baselines/reference/logicalAndOperatorWithEveryType.types
index b2628eed9219f..bd913e94da58c 100644
--- a/tests/baselines/reference/logicalAndOperatorWithEveryType.types
+++ b/tests/baselines/reference/logicalAndOperatorWithEveryType.types
@@ -623,7 +623,7 @@ var rj8 = a8 && undefined;
var rj9 = null && undefined;
>rj9 : any
->null && undefined : null
+>null && undefined : undefined
>null : null
>undefined : undefined
diff --git a/tests/baselines/reference/objectLiteralWidened.js b/tests/baselines/reference/objectLiteralWidened.js
index 4de228cb14a7f..98d79133540bd 100644
--- a/tests/baselines/reference/objectLiteralWidened.js
+++ b/tests/baselines/reference/objectLiteralWidened.js
@@ -1,29 +1,61 @@
//// [objectLiteralWidened.ts]
// object literal properties are widened to any
-var x = {
+var x1 = {
foo: null,
bar: undefined
}
-var y = {
+var y1 = {
foo: null,
bar: {
baz: null,
boo: undefined
}
+}
+
+// these are not widened
+
+var u: undefined = undefined;
+var n: null = null;
+
+var x2 = {
+ foo: n,
+ bar: u
+}
+
+var y2 = {
+ foo: n,
+ bar: {
+ baz: n,
+ boo: u
+ }
}
//// [objectLiteralWidened.js]
// object literal properties are widened to any
-var x = {
+var x1 = {
foo: null,
bar: undefined
};
-var y = {
+var y1 = {
foo: null,
bar: {
baz: null,
boo: undefined
}
};
+// these are not widened
+var u = undefined;
+var n = null;
+var x2 = {
+ foo: n,
+ bar: u
+};
+var y2 = {
+ foo: n,
+ bar: {
+ baz: n,
+ boo: u
+ }
+};
diff --git a/tests/baselines/reference/objectLiteralWidened.symbols b/tests/baselines/reference/objectLiteralWidened.symbols
index 0bf077cd9d8a1..4b2a1b4a00185 100644
--- a/tests/baselines/reference/objectLiteralWidened.symbols
+++ b/tests/baselines/reference/objectLiteralWidened.symbols
@@ -1,22 +1,22 @@
=== tests/cases/conformance/types/typeRelationships/widenedTypes/objectLiteralWidened.ts ===
// object literal properties are widened to any
-var x = {
->x : Symbol(x, Decl(objectLiteralWidened.ts, 2, 3))
+var x1 = {
+>x1 : Symbol(x1, Decl(objectLiteralWidened.ts, 2, 3))
foo: null,
->foo : Symbol(foo, Decl(objectLiteralWidened.ts, 2, 9))
+>foo : Symbol(foo, Decl(objectLiteralWidened.ts, 2, 10))
bar: undefined
>bar : Symbol(bar, Decl(objectLiteralWidened.ts, 3, 14))
>undefined : Symbol(undefined)
}
-var y = {
->y : Symbol(y, Decl(objectLiteralWidened.ts, 7, 3))
+var y1 = {
+>y1 : Symbol(y1, Decl(objectLiteralWidened.ts, 7, 3))
foo: null,
->foo : Symbol(foo, Decl(objectLiteralWidened.ts, 7, 9))
+>foo : Symbol(foo, Decl(objectLiteralWidened.ts, 7, 10))
bar: {
>bar : Symbol(bar, Decl(objectLiteralWidened.ts, 8, 14))
@@ -29,3 +29,44 @@ var y = {
>undefined : Symbol(undefined)
}
}
+
+// these are not widened
+
+var u: undefined = undefined;
+>u : Symbol(u, Decl(objectLiteralWidened.ts, 17, 3))
+>undefined : Symbol(undefined)
+
+var n: null = null;
+>n : Symbol(n, Decl(objectLiteralWidened.ts, 18, 3))
+
+var x2 = {
+>x2 : Symbol(x2, Decl(objectLiteralWidened.ts, 20, 3))
+
+ foo: n,
+>foo : Symbol(foo, Decl(objectLiteralWidened.ts, 20, 10))
+>n : Symbol(n, Decl(objectLiteralWidened.ts, 18, 3))
+
+ bar: u
+>bar : Symbol(bar, Decl(objectLiteralWidened.ts, 21, 11))
+>u : Symbol(u, Decl(objectLiteralWidened.ts, 17, 3))
+}
+
+var y2 = {
+>y2 : Symbol(y2, Decl(objectLiteralWidened.ts, 25, 3))
+
+ foo: n,
+>foo : Symbol(foo, Decl(objectLiteralWidened.ts, 25, 10))
+>n : Symbol(n, Decl(objectLiteralWidened.ts, 18, 3))
+
+ bar: {
+>bar : Symbol(bar, Decl(objectLiteralWidened.ts, 26, 11))
+
+ baz: n,
+>baz : Symbol(baz, Decl(objectLiteralWidened.ts, 27, 10))
+>n : Symbol(n, Decl(objectLiteralWidened.ts, 18, 3))
+
+ boo: u
+>boo : Symbol(boo, Decl(objectLiteralWidened.ts, 28, 15))
+>u : Symbol(u, Decl(objectLiteralWidened.ts, 17, 3))
+ }
+}
diff --git a/tests/baselines/reference/objectLiteralWidened.types b/tests/baselines/reference/objectLiteralWidened.types
index 9f47e47795d56..66309202617d9 100644
--- a/tests/baselines/reference/objectLiteralWidened.types
+++ b/tests/baselines/reference/objectLiteralWidened.types
@@ -1,8 +1,8 @@
=== tests/cases/conformance/types/typeRelationships/widenedTypes/objectLiteralWidened.ts ===
// object literal properties are widened to any
-var x = {
->x : { foo: any; bar: any; }
+var x1 = {
+>x1 : { foo: any; bar: any; }
>{ foo: null, bar: undefined} : { foo: null; bar: undefined; }
foo: null,
@@ -14,8 +14,8 @@ var x = {
>undefined : undefined
}
-var y = {
->y : { foo: any; bar: { baz: any; boo: any; }; }
+var y1 = {
+>y1 : { foo: any; bar: { baz: any; boo: any; }; }
>{ foo: null, bar: { baz: null, boo: undefined }} : { foo: null; bar: { baz: null; boo: undefined; }; }
foo: null,
@@ -35,3 +35,49 @@ var y = {
>undefined : undefined
}
}
+
+// these are not widened
+
+var u: undefined = undefined;
+>u : undefined
+>undefined : undefined
+
+var n: null = null;
+>n : null
+>null : null
+>null : null
+
+var x2 = {
+>x2 : { foo: null; bar: undefined; }
+>{ foo: n, bar: u} : { foo: null; bar: undefined; }
+
+ foo: n,
+>foo : null
+>n : null
+
+ bar: u
+>bar : undefined
+>u : undefined
+}
+
+var y2 = {
+>y2 : { foo: null; bar: { baz: null; boo: undefined; }; }
+>{ foo: n, bar: { baz: n, boo: u }} : { foo: null; bar: { baz: null; boo: undefined; }; }
+
+ foo: n,
+>foo : null
+>n : null
+
+ bar: {
+>bar : { baz: null; boo: undefined; }
+>{ baz: n, boo: u } : { baz: null; boo: undefined; }
+
+ baz: n,
+>baz : null
+>n : null
+
+ boo: u
+>boo : undefined
+>u : undefined
+ }
+}
diff --git a/tests/baselines/reference/strictNullChecksNoWidening.js b/tests/baselines/reference/strictNullChecksNoWidening.js
new file mode 100644
index 0000000000000..ba26a04fc131a
--- /dev/null
+++ b/tests/baselines/reference/strictNullChecksNoWidening.js
@@ -0,0 +1,31 @@
+//// [strictNullChecksNoWidening.ts]
+
+var a1 = null;
+var a2 = undefined;
+var a3 = void 0;
+
+var b1 = [];
+var b2 = [,];
+var b3 = [undefined];
+var b4 = [[], []];
+var b5 = [[], [,]];
+
+declare function f<T>(x: T): T;
+
+var c1 = f(null);
+var c2 = f(undefined);
+var c3 = f([]);
+
+
+//// [strictNullChecksNoWidening.js]
+var a1 = null;
+var a2 = undefined;
+var a3 = void 0;
+var b1 = [];
+var b2 = [,];
+var b3 = [undefined];
+var b4 = [[], []];
+var b5 = [[], [,]];
+var c1 = f(null);
+var c2 = f(undefined);
+var c3 = f([]);
diff --git a/tests/baselines/reference/strictNullChecksNoWidening.symbols b/tests/baselines/reference/strictNullChecksNoWidening.symbols
new file mode 100644
index 0000000000000..a23a0d2e926c0
--- /dev/null
+++ b/tests/baselines/reference/strictNullChecksNoWidening.symbols
@@ -0,0 +1,48 @@
+=== tests/cases/conformance/types/typeRelationships/widenedTypes/strictNullChecksNoWidening.ts ===
+
+var a1 = null;
+>a1 : Symbol(a1, Decl(strictNullChecksNoWidening.ts, 1, 3))
+
+var a2 = undefined;
+>a2 : Symbol(a2, Decl(strictNullChecksNoWidening.ts, 2, 3))
+>undefined : Symbol(undefined)
+
+var a3 = void 0;
+>a3 : Symbol(a3, Decl(strictNullChecksNoWidening.ts, 3, 3))
+
+var b1 = [];
+>b1 : Symbol(b1, Decl(strictNullChecksNoWidening.ts, 5, 3))
+
+var b2 = [,];
+>b2 : Symbol(b2, Decl(strictNullChecksNoWidening.ts, 6, 3))
+
+var b3 = [undefined];
+>b3 : Symbol(b3, Decl(strictNullChecksNoWidening.ts, 7, 3))
+>undefined : Symbol(undefined)
+
+var b4 = [[], []];
+>b4 : Symbol(b4, Decl(strictNullChecksNoWidening.ts, 8, 3))
+
+var b5 = [[], [,]];
+>b5 : Symbol(b5, Decl(strictNullChecksNoWidening.ts, 9, 3))
+
+declare function f<T>(x: T): T;
+>f : Symbol(f, Decl(strictNullChecksNoWidening.ts, 9, 19))
+>T : Symbol(T, Decl(strictNullChecksNoWidening.ts, 11, 19))
+>x : Symbol(x, Decl(strictNullChecksNoWidening.ts, 11, 22))
+>T : Symbol(T, Decl(strictNullChecksNoWidening.ts, 11, 19))
+>T : Symbol(T, Decl(strictNullChecksNoWidening.ts, 11, 19))
+
+var c1 = f(null);
+>c1 : Symbol(c1, Decl(strictNullChecksNoWidening.ts, 13, 3))
+>f : Symbol(f, Decl(strictNullChecksNoWidening.ts, 9, 19))
+
+var c2 = f(undefined);
+>c2 : Symbol(c2, Decl(strictNullChecksNoWidening.ts, 14, 3))
+>f : Symbol(f, Decl(strictNullChecksNoWidening.ts, 9, 19))
+>undefined : Symbol(undefined)
+
+var c3 = f([]);
+>c3 : Symbol(c3, Decl(strictNullChecksNoWidening.ts, 15, 3))
+>f : Symbol(f, Decl(strictNullChecksNoWidening.ts, 9, 19))
+
diff --git a/tests/baselines/reference/strictNullChecksNoWidening.types b/tests/baselines/reference/strictNullChecksNoWidening.types
new file mode 100644
index 0000000000000..6dd2ee3fb4cfb
--- /dev/null
+++ b/tests/baselines/reference/strictNullChecksNoWidening.types
@@ -0,0 +1,67 @@
+=== tests/cases/conformance/types/typeRelationships/widenedTypes/strictNullChecksNoWidening.ts ===
+
+var a1 = null;
+>a1 : null
+>null : null
+
+var a2 = undefined;
+>a2 : undefined
+>undefined : undefined
+
+var a3 = void 0;
+>a3 : undefined
+>void 0 : undefined
+>0 : number
+
+var b1 = [];
+>b1 : never[]
+>[] : never[]
+
+var b2 = [,];
+>b2 : undefined[]
+>[,] : undefined[]
+> : undefined
+
+var b3 = [undefined];
+>b3 : undefined[]
+>[undefined] : undefined[]
+>undefined : undefined
+
+var b4 = [[], []];
+>b4 : never[][]
+>[[], []] : never[][]
+>[] : never[]
+>[] : never[]
+
+var b5 = [[], [,]];
+>b5 : undefined[][]
+>[[], [,]] : undefined[][]
+>[] : never[]
+>[,] : undefined[]
+> : undefined
+
+declare function f<T>(x: T): T;
+>f : <T>(x: T) => T
+>T : T
+>x : T
+>T : T
+>T : T
+
+var c1 = f(null);
+>c1 : null
+>f(null) : null
+>f : <T>(x: T) => T
+>null : null
+
+var c2 = f(undefined);
+>c2 : undefined
+>f(undefined) : undefined
+>f : <T>(x: T) => T
+>undefined : undefined
+
+var c3 = f([]);
+>c3 : never[]
+>f([]) : never[]
+>f : <T>(x: T) => T
+>[] : never[]
+
diff --git a/tests/cases/conformance/types/typeRelationships/widenedTypes/arrayLiteralWidened.ts b/tests/cases/conformance/types/typeRelationships/widenedTypes/arrayLiteralWidened.ts
index 8af0a5842cc2e..05428422129c6 100644
--- a/tests/cases/conformance/types/typeRelationships/widenedTypes/arrayLiteralWidened.ts
+++ b/tests/cases/conformance/types/typeRelationships/widenedTypes/arrayLiteralWidened.ts
@@ -1,6 +1,7 @@
// array literals are widened upon assignment according to their element type
var a = []; // any[]
+var a = [,,];
var a = [null, null];
var a = [undefined, undefined];
@@ -11,3 +12,11 @@ var b = [[undefined, undefined]];
var c = [[[]]]; // any[][][]
var c = [[[null]],[undefined]]
+
+// no widening when one or more elements are non-widening
+
+var x: undefined = undefined;
+
+var d = [x];
+var d = [, x];
+var d = [undefined, x];
diff --git a/tests/cases/conformance/types/typeRelationships/widenedTypes/initializersWidened.ts b/tests/cases/conformance/types/typeRelationships/widenedTypes/initializersWidened.ts
index e79cdc9e16834..2eeb96194b753 100644
--- a/tests/cases/conformance/types/typeRelationships/widenedTypes/initializersWidened.ts
+++ b/tests/cases/conformance/types/typeRelationships/widenedTypes/initializersWidened.ts
@@ -1,4 +1,24 @@
// these are widened to any at the point of assignment
-var x = null;
-var y = undefined;
\ No newline at end of file
+var x1 = null;
+var y1 = undefined;
+var z1 = void 0;
+
+// these are not widened
+
+var x2: null;
+var y2: undefined;
+
+var x3: null = null;
+var y3: undefined = undefined;
+var z3: undefined = void 0;
+
+// widen only when all constituents of union are widening
+
+var x4 = null || null;
+var y4 = undefined || undefined;
+var z4 = void 0 || void 0;
+
+var x5 = null || x2;
+var y5 = undefined || y2;
+var z5 = void 0 || y2;
\ No newline at end of file
diff --git a/tests/cases/conformance/types/typeRelationships/widenedTypes/objectLiteralWidened.ts b/tests/cases/conformance/types/typeRelationships/widenedTypes/objectLiteralWidened.ts
index cde44f9116856..8b51e526882e7 100644
--- a/tests/cases/conformance/types/typeRelationships/widenedTypes/objectLiteralWidened.ts
+++ b/tests/cases/conformance/types/typeRelationships/widenedTypes/objectLiteralWidened.ts
@@ -1,14 +1,32 @@
// object literal properties are widened to any
-var x = {
+var x1 = {
foo: null,
bar: undefined
}
-var y = {
+var y1 = {
foo: null,
bar: {
baz: null,
boo: undefined
}
+}
+
+// these are not widened
+
+var u: undefined = undefined;
+var n: null = null;
+
+var x2 = {
+ foo: n,
+ bar: u
+}
+
+var y2 = {
+ foo: n,
+ bar: {
+ baz: n,
+ boo: u
+ }
}
\ No newline at end of file
diff --git a/tests/cases/conformance/types/typeRelationships/widenedTypes/strictNullChecksNoWidening.ts b/tests/cases/conformance/types/typeRelationships/widenedTypes/strictNullChecksNoWidening.ts
new file mode 100644
index 0000000000000..8f5b4709abf9e
--- /dev/null
+++ b/tests/cases/conformance/types/typeRelationships/widenedTypes/strictNullChecksNoWidening.ts
@@ -0,0 +1,17 @@
+// @strictNullChecks: true
+
+var a1 = null;
+var a2 = undefined;
+var a3 = void 0;
+
+var b1 = [];
+var b2 = [,];
+var b3 = [undefined];
+var b4 = [[], []];
+var b5 = [[], [,]];
+
+declare function f<T>(x: T): T;
+
+var c1 = f(null);
+var c2 = f(undefined);
+var c3 = f([]);
From fb2df77a59453e72e3bbc92ab4bb9e5c68cb4a8a Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Thu, 2 Jun 2016 10:47:47 -0700
Subject: [PATCH 3/3] Remove unused variable
---
src/compiler/checker.ts | 1 -
1 file changed, 1 deletion(-)
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 6166234dcf4d3..b8f078ea9a56b 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -120,7 +120,6 @@ namespace ts {
const undefinedWideningType = strictNullChecks ? undefinedType : createIntrinsicType(TypeFlags.Undefined | TypeFlags.ContainsWideningType, "undefined");
const nullType = createIntrinsicType(TypeFlags.Null, "null");
const nullWideningType = strictNullChecks ? nullType : createIntrinsicType(TypeFlags.Null | TypeFlags.ContainsWideningType, "null");
- const emptyArrayElementType = createIntrinsicType(TypeFlags.Undefined | TypeFlags.ContainsWideningType, "undefined");
const unknownType = createIntrinsicType(TypeFlags.Any, "unknown");
const neverType = createIntrinsicType(TypeFlags.Never, "never");