Skip to content

Fix initializer widening #29192

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 4 commits into from
Dec 29, 2018
Merged

Fix initializer widening #29192

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
0165e80
Don't widen contextually typed literals in initializer expressions
ahejlsberg Dec 28, 2018
93b4302
Accept new baselines
ahejlsberg Dec 28, 2018
7f4d1ac
Add regression test
ahejlsberg Dec 28, 2018
73b1dcb
Accept new baselines
ahejlsberg Dec 28, 2018
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 3 additions & 2 deletions src/compiler/checker.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4919,7 +4919,7 @@ namespace ts {
if (strictNullChecks && declaration.initializer && !(getFalsyFlags(checkDeclarationInitializer(declaration)) & TypeFlags.Undefined)) {
type = getTypeWithFacts(type, TypeFacts.NEUndefined);
}
return declaration.initializer && !getContextualTypeForVariableLikeDeclaration(walkUpBindingElementsAndPatterns(declaration)) ?
return declaration.initializer && !getEffectiveTypeAnnotationNode(walkUpBindingElementsAndPatterns(declaration)) ?
Copy link
Member

@weswigham weswigham Dec 28, 2018 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I'm not sure I think this is right to change. Outside of strict mode, I believe this is going to make a destructured variable with an undefined initializer (with a contextual type) be any instead of the correct contextual type.

Copy link
Member Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

It's the right change (it basically just reverts the change that you had made). In classic checking mode this makes a variable of type string as expected.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Aight, ok then

getUnionType([type, checkDeclarationInitializer(declaration)], UnionReduction.Subtype) :
type;
}
Expand Down Expand Up @@ -22810,7 +22810,8 @@ namespace ts {
const type = getTypeOfExpression(initializer, /*cache*/ true);
const widened = getCombinedNodeFlags(declaration) & NodeFlags.Const ||
isDeclarationReadonly(declaration) ||
isTypeAssertion(initializer) ? type : getWidenedLiteralType(type);
isTypeAssertion(initializer) ||
isLiteralOfContextualType(type, getContextualType(initializer)) ? type : getWidenedLiteralType(type);
if (isInJSFile(declaration)) {
if (widened.flags & TypeFlags.Nullable) {
reportImplicitAny(declaration, anyType);
Expand Down
4 changes: 2 additions & 2 deletions tests/baselines/reference/destructuringArrayBindingPatternAndAssignment3.types
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -45,8 +45,8 @@ const [f, g = f, h = i, i = f] = [1]; // error for h = i
>c : number
>d : number
>c : number
>e : number
>e : number
>e : any
>e : any

})([1]);
>[1] : number[]
Expand Down
13 changes: 12 additions & 1 deletion tests/baselines/reference/destructuringInitializerContextualTypeFromContext.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -17,9 +17,16 @@ const Child: SFC<Props> = ({
children,
name = "Artemis",
...props
}) => `name: ${name} props: ${JSON.stringify(props)}`;
}) => `name: ${name} props: ${JSON.stringify(props)}`;

// Repro from #29189

declare function f(g: (as: string[]) => void): void
f(([_1, _2 = undefined]) => undefined)


//// [destructuringInitializerContextualTypeFromContext.js]
"use strict";
var __assign = (this && this.__assign) || function () {
__assign = Object.assign || function(t) {
for (var s, i = 1, n = arguments.length; i < n; i++) {
Expand Down Expand Up @@ -48,3 +55,7 @@ var Child = function (_a) {
var children = _a.children, _b = _a.name, name = _b === void 0 ? "Artemis" : _b, props = __rest(_a, ["children", "name"]);
return "name: " + name + " props: " + JSON.stringify(props);
};
f(function (_a) {
var _1 = _a[0], _b = _a[1], _2 = _b === void 0 ? undefined : _b;
return undefined;
});
14 changes: 14 additions & 0 deletions tests/baselines/reference/destructuringInitializerContextualTypeFromContext.symbols
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -56,3 +56,17 @@ const Child: SFC<Props> = ({
>stringify : Symbol(JSON.stringify, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
>props : Symbol(props, Decl(destructuringInitializerContextualTypeFromContext.ts, 16, 21))

// Repro from #29189

declare function f(g: (as: string[]) => void): void
>f : Symbol(f, Decl(destructuringInitializerContextualTypeFromContext.ts, 18, 54))
>g : Symbol(g, Decl(destructuringInitializerContextualTypeFromContext.ts, 22, 19))
>as : Symbol(as, Decl(destructuringInitializerContextualTypeFromContext.ts, 22, 23))

f(([_1, _2 = undefined]) => undefined)
>f : Symbol(f, Decl(destructuringInitializerContextualTypeFromContext.ts, 18, 54))
>_1 : Symbol(_1, Decl(destructuringInitializerContextualTypeFromContext.ts, 23, 4))
>_2 : Symbol(_2, Decl(destructuringInitializerContextualTypeFromContext.ts, 23, 7))
>undefined : Symbol(undefined)
>undefined : Symbol(undefined)

20 changes: 18 additions & 2 deletions tests/baselines/reference/destructuringInitializerContextualTypeFromContext.types
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -50,8 +50,24 @@ const Child: SFC<Props> = ({
>`name: ${name} props: ${JSON.stringify(props)}` : string
>name : "Apollo" | "Artemis" | "Dionysus" | "Persephone"
>JSON.stringify(props) : string
>JSON.stringify : { (value: any, replacer?: (key: string, value: any) => any, space?: string | number): string; (value: any, replacer?: (string | number)[], space?: string | number): string; }
>JSON.stringify : { (value: any, replacer?: ((key: string, value: any) => any) | undefined, space?: string | number | undefined): string; (value: any, replacer?: (string | number)[] | null | undefined, space?: string | number | undefined): string; }
>JSON : JSON
>stringify : { (value: any, replacer?: (key: string, value: any) => any, space?: string | number): string; (value: any, replacer?: (string | number)[], space?: string | number): string; }
>stringify : { (value: any, replacer?: ((key: string, value: any) => any) | undefined, space?: string | number | undefined): string; (value: any, replacer?: (string | number)[] | null | undefined, space?: string | number | undefined): string; }
>props : {}

// Repro from #29189

declare function f(g: (as: string[]) => void): void
>f : (g: (as: string[]) => void) => void
>g : (as: string[]) => void
>as : string[]

f(([_1, _2 = undefined]) => undefined)
>f(([_1, _2 = undefined]) => undefined) : void
>f : (g: (as: string[]) => void) => void
>([_1, _2 = undefined]) => undefined : ([_1, _2]: string[]) => undefined
>_1 : string
>_2 : string | undefined
>undefined : undefined
>undefined : undefined

9 changes: 8 additions & 1 deletion tests/cases/compiler/destructuringInitializerContextualTypeFromContext.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,3 +1,5 @@
// @strict: true

interface SFC<P = {}> {
(props: P & { children?: any }): any | null;
}
Expand All @@ -16,4 +18,9 @@ const Child: SFC<Props> = ({
children,
name = "Artemis",
...props
}) => `name: ${name} props: ${JSON.stringify(props)}`;
}) => `name: ${name} props: ${JSON.stringify(props)}`;

// Repro from #29189

declare function f(g: (as: string[]) => void): void
f(([_1, _2 = undefined]) => undefined)