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Merge pull request #28112 from Microsoft/fixInstanceofControlFlow

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Fix instanceof control flow analysis
This commit is contained in:
Anders Hejlsberg
2018-10-25 06:16:39 -07:00
committed by GitHub
parent 42740d66c2 cc9f45d517
commit 6e8e5c10dd
6 changed files with 201 additions and 24 deletions
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src/compiler/checker.ts
+11 -6
View File
@@ -14340,6 +14340,11 @@ namespace ts {
return false;
}
function hasNarrowableDeclaredType(expr: Node) {
const type = getDeclaredTypeOfReference(expr);
return !!(type && type.flags & TypeFlags.Union);
}
function findDiscriminantProperties(sourceProperties: Symbol[], target: Type): Symbol[] | undefined {
let result: Symbol[] | undefined;
for (const sourceProperty of sourceProperties) {
@@ -15373,9 +15378,9 @@ namespace ts {
// We have '==', '!=', '====', or !==' operator with 'typeof xxx' and string literal operands
const target = getReferenceCandidate(typeOfExpr.expression);
if (!isMatchingReference(reference, target)) {
// For a reference of the form 'x.y', a 'typeof x === ...' type guard resets the
// narrowed type of 'y' to its declared type.
if (containsMatchingReference(reference, target)) {
// For a reference of the form 'x.y', where 'x' has a narrowable declared type, a
// 'typeof x === ...' type guard resets the narrowed type of 'y' to its declared type.
if (containsMatchingReference(reference, target) && hasNarrowableDeclaredType(target)) {
return declaredType;
}
return type;
@@ -15516,9 +15521,9 @@ namespace ts {
function narrowTypeByInstanceof(type: Type, expr: BinaryExpression, assumeTrue: boolean): Type {
const left = getReferenceCandidate(expr.left);
if (!isMatchingReference(reference, left)) {
// For a reference of the form 'x.y', an 'x instanceof T' type guard resets the
// narrowed type of 'y' to its declared type.
if (containsMatchingReference(reference, left)) {
// For a reference of the form 'x.y', where 'x' has a narrowable declared type, an
// 'x instanceof T' type guard resets the narrowed type of 'y' to its declared type.
if (containsMatchingReference(reference, left) && hasNarrowableDeclaredType(left)) {
return declaredType;
}
return type;
tests/baselines/reference/narrowingOfDottedNames.errors.txt
+67
View File
@@ -0,0 +1,67 @@
tests/cases/compiler/narrowingOfDottedNames.ts(45,5): error TS2564: Property 'x' has no initializer and is not definitely assigned in the constructor.
tests/cases/compiler/narrowingOfDottedNames.ts(54,5): error TS2564: Property 'x' has no initializer and is not definitely assigned in the constructor.
==== tests/cases/compiler/narrowingOfDottedNames.ts (2 errors) ====
// Repro from #8383
class A {
prop!: { a: string; };
}
class B {
prop!: { b: string; }
}
function isA(x: any): x is A {
return x instanceof A;
}
function isB(x: any): x is B {
return x instanceof B;
}
function f1(x: A | B) {
while (true) {
if (x instanceof A) {
x.prop.a;
}
else if (x instanceof B) {
x.prop.b;
}
}
}
function f2(x: A | B) {
while (true) {
if (isA(x)) {
x.prop.a;
}
else if (isB(x)) {
x.prop.b;
}
}
}
// Repro from #28100
class Foo1
{
x: number; // Error
~
!!! error TS2564: Property 'x' has no initializer and is not definitely assigned in the constructor.
constructor() {
if (this instanceof Boolean) {
}
}
}
class Foo2
{
x: number; // Error
~
!!! error TS2564: Property 'x' has no initializer and is not definitely assigned in the constructor.
constructor() {
}
}
tests/baselines/reference/narrowingOfDottedNames.js
+34 -2
View File
@@ -2,11 +2,11 @@
// Repro from #8383
class A {
prop: { a: string; };
prop!: { a: string; };
}
class B {
prop: { b: string; }
prop!: { b: string; }
}
function isA(x: any): x is A {
@@ -38,9 +38,28 @@ function f2(x: A | B) {
}
}
}
// Repro from #28100
class Foo1
{
x: number; // Error
constructor() {
if (this instanceof Boolean) {
}
}
}
class Foo2
{
x: number; // Error
constructor() {
}
}
//// [narrowingOfDottedNames.js]
"use strict";
// Repro from #8383
var A = /** @class */ (function () {
function A() {
@@ -78,3 +97,16 @@ function f2(x) {
}
}
}
// Repro from #28100
var Foo1 = /** @class */ (function () {
function Foo1() {
if (this instanceof Boolean) {
}
}
return Foo1;
}());
var Foo2 = /** @class */ (function () {
function Foo2() {
}
return Foo2;
}());
tests/baselines/reference/narrowingOfDottedNames.symbols
+38 -12
View File
@@ -4,17 +4,17 @@
class A {
>A : Symbol(A, Decl(narrowingOfDottedNames.ts, 0, 0))
prop: { a: string; };
prop!: { a: string; };
>prop : Symbol(A.prop, Decl(narrowingOfDottedNames.ts, 2, 9))
>a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 11))
>a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 12))
}
class B {
>B : Symbol(B, Decl(narrowingOfDottedNames.ts, 4, 1))
prop: { b: string; }
prop!: { b: string; }
>prop : Symbol(B.prop, Decl(narrowingOfDottedNames.ts, 6, 9))
>b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 11))
>b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 12))
}
function isA(x: any): x is A {
@@ -51,22 +51,22 @@ function f1(x: A | B) {
>A : Symbol(A, Decl(narrowingOfDottedNames.ts, 0, 0))
x.prop.a;
>x.prop.a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 11))
>x.prop.a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 12))
>x.prop : Symbol(A.prop, Decl(narrowingOfDottedNames.ts, 2, 9))
>x : Symbol(x, Decl(narrowingOfDottedNames.ts, 18, 12))
>prop : Symbol(A.prop, Decl(narrowingOfDottedNames.ts, 2, 9))
>a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 11))
>a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 12))
}
else if (x instanceof B) {
>x : Symbol(x, Decl(narrowingOfDottedNames.ts, 18, 12))
>B : Symbol(B, Decl(narrowingOfDottedNames.ts, 4, 1))
x.prop.b;
>x.prop.b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 11))
>x.prop.b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 12))
>x.prop : Symbol(B.prop, Decl(narrowingOfDottedNames.ts, 6, 9))
>x : Symbol(x, Decl(narrowingOfDottedNames.ts, 18, 12))
>prop : Symbol(B.prop, Decl(narrowingOfDottedNames.ts, 6, 9))
>b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 11))
>b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 12))
}
}
}
@@ -83,23 +83,49 @@ function f2(x: A | B) {
>x : Symbol(x, Decl(narrowingOfDottedNames.ts, 29, 12))
x.prop.a;
>x.prop.a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 11))
>x.prop.a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 12))
>x.prop : Symbol(A.prop, Decl(narrowingOfDottedNames.ts, 2, 9))
>x : Symbol(x, Decl(narrowingOfDottedNames.ts, 29, 12))
>prop : Symbol(A.prop, Decl(narrowingOfDottedNames.ts, 2, 9))
>a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 11))
>a : Symbol(a, Decl(narrowingOfDottedNames.ts, 3, 12))
}
else if (isB(x)) {
>isB : Symbol(isB, Decl(narrowingOfDottedNames.ts, 12, 1))
>x : Symbol(x, Decl(narrowingOfDottedNames.ts, 29, 12))
x.prop.b;
>x.prop.b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 11))
>x.prop.b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 12))
>x.prop : Symbol(B.prop, Decl(narrowingOfDottedNames.ts, 6, 9))
>x : Symbol(x, Decl(narrowingOfDottedNames.ts, 29, 12))
>prop : Symbol(B.prop, Decl(narrowingOfDottedNames.ts, 6, 9))
>b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 11))
>b : Symbol(b, Decl(narrowingOfDottedNames.ts, 7, 12))
}
}
}
// Repro from #28100
class Foo1
>Foo1 : Symbol(Foo1, Decl(narrowingOfDottedNames.ts, 38, 1))
{
x: number; // Error
>x : Symbol(Foo1.x, Decl(narrowingOfDottedNames.ts, 43, 1))
constructor() {
if (this instanceof Boolean) {
>this : Symbol(Foo1, Decl(narrowingOfDottedNames.ts, 38, 1))
>Boolean : Symbol(Boolean, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
}
}
}
class Foo2
>Foo2 : Symbol(Foo2, Decl(narrowingOfDottedNames.ts, 49, 1))
{
x: number; // Error
>x : Symbol(Foo2.x, Decl(narrowingOfDottedNames.ts, 52, 1))
constructor() {
}
}
tests/baselines/reference/narrowingOfDottedNames.types
+29 -2
View File
@@ -4,7 +4,7 @@
class A {
>A : A
prop: { a: string; };
prop!: { a: string; };
>prop : { a: string; }
>a : string
}
@@ -12,7 +12,7 @@ class A {
class B {
>B : B
prop: { b: string; }
prop!: { b: string; }
>prop : { b: string; }
>b : string
}
@@ -105,3 +105,30 @@ function f2(x: A | B) {
}
}
// Repro from #28100
class Foo1
>Foo1 : Foo1
{
x: number; // Error
>x : number
constructor() {
if (this instanceof Boolean) {
>this instanceof Boolean : boolean
>this : this
>Boolean : BooleanConstructor
}
}
}
class Foo2
>Foo2 : Foo2
{
x: number; // Error
>x : number
constructor() {
}
}
tests/cases/compiler/narrowingOfDottedNames.ts
+22 -2
View File
@@ -1,11 +1,13 @@
// @strict: true
// Repro from #8383
class A {
prop: { a: string; };
prop!: { a: string; };
}
class B {
prop: { b: string; }
prop!: { b: string; }
}
function isA(x: any): x is A {
@@ -37,3 +39,21 @@ function f2(x: A | B) {
}
}
}
// Repro from #28100
class Foo1
{
x: number; // Error
constructor() {
if (this instanceof Boolean) {
}
}
}
class Foo2
{
x: number; // Error
constructor() {
}
}