Skip to content

Un‑consolidate and fix WeakMap constructor overloads #56713

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
jakebailey merged 3 commits into from
Feb 7, 2026
+28 −12
Merged

Un‑consolidate and fix WeakMap constructor overloads #56713

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
ed75be4
Un‑consolidate and fix `WeakMap` constructor overloads
ExE-Boss Nov 22, 2020
5740829
Merge branch 'main' into pr-56713
jakebailey Feb 6, 2026
411d4e7
update baselines
jakebailey Feb 6, 2026
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
2 changes: 1 addition & 1 deletion src/lib/es2015.iterable.d.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -168,7 +168,7 @@ interface MapConstructor {
interface WeakMap<K extends WeakKey, V> {}

interface WeakMapConstructor {
new <K extends WeakKey, V>(iterable: Iterable<readonly [K, V]>): WeakMap<K, V>;
new <K extends WeakKey = WeakKey, V = any>(iterable?: Iterable<readonly [K, V]> | null): WeakMap<K, V>;
}

interface SetIterator<T> extends IteratorObject<T, BuiltinIteratorReturn, unknown> {
Expand Down
4 changes: 2 additions & 2 deletions tests/baselines/reference/dissallowSymbolAsWeakType.errors.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -12,7 +12,7 @@ dissallowSymbolAsWeakType.ts(4,8): error TS2345: Argument of type 'symbol' is no
dissallowSymbolAsWeakType.ts(5,8): error TS2345: Argument of type 'symbol' is not assignable to parameter of type 'object'.
dissallowSymbolAsWeakType.ts(6,11): error TS2345: Argument of type 'symbol' is not assignable to parameter of type 'object'.
dissallowSymbolAsWeakType.ts(8,16): error TS2769: No overload matches this call.
Overload 1 of 2, '(iterable: Iterable<readonly [object, boolean]>): WeakMap<object, boolean>', gave the following error.
Overload 1 of 2, '(iterable?: Iterable<readonly [object, boolean]> | null | undefined): WeakMap<object, boolean>', gave the following error.
Argument of type '[symbol, false][]' is not assignable to parameter of type 'Iterable<readonly [object, boolean]>'.
The types returned by '[Symbol.iterator]().next(...)' are incompatible between these types.
Type 'IteratorResult<[symbol, false], undefined>' is not assignable to type 'IteratorResult<readonly [object, boolean], any>'.
Expand Down Expand Up @@ -60,7 +60,7 @@ dissallowSymbolAsWeakType.ts(19,14): error TS2345: Argument of type 'symbol' is
const wm = new WeakMap([[s, false]]);
~~~~~~~
!!! error TS2769: No overload matches this call.
!!! error TS2769: Overload 1 of 2, '(iterable: Iterable<readonly [object, boolean]>): WeakMap<object, boolean>', gave the following error.
!!! error TS2769: Overload 1 of 2, '(iterable?: Iterable<readonly [object, boolean]> | null | undefined): WeakMap<object, boolean>', gave the following error.
!!! error TS2769: Argument of type '[symbol, false][]' is not assignable to parameter of type 'Iterable<readonly [object, boolean]>'.
!!! error TS2769: The types returned by '[Symbol.iterator]().next(...)' are incompatible between these types.
!!! error TS2769: Type 'IteratorResult<[symbol, false], undefined>' is not assignable to type 'IteratorResult<readonly [object, boolean], any>'.
Expand Down
13 changes: 7 additions & 6 deletions ...reference/extendingSetWithCheckJs.symbols → ...e/extendingCollectionsWithCheckJs.symbols
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,8 +1,8 @@
//// [tests/cases/compiler/extendingSetWithCheckJs.ts] ////
//// [tests/cases/compiler/extendingCollectionsWithCheckJs.ts] ////

=== extendingSetWithCheckJs.ts ===
=== extendingCollectionsWithCheckJs.js ===
class MySet extends Set {
>MySet : Symbol(MySet, Decl(extendingSetWithCheckJs.ts, 0, 0))
>MySet : Symbol(MySet, Decl(extendingCollectionsWithCheckJs.js, 0, 0))
>Set : Symbol(Set, Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.iterable.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))

constructor() {
Expand All @@ -12,7 +12,7 @@ class MySet extends Set {
}

class MyWeakSet extends WeakSet {
>MyWeakSet : Symbol(MyWeakSet, Decl(extendingSetWithCheckJs.ts, 4, 1))
>MyWeakSet : Symbol(MyWeakSet, Decl(extendingCollectionsWithCheckJs.js, 4, 1))
>WeakSet : Symbol(WeakSet, Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.iterable.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))

constructor() {
Expand All @@ -22,7 +22,7 @@ class MyWeakSet extends WeakSet {
}

class MyMap extends Map {
>MyMap : Symbol(MyMap, Decl(extendingSetWithCheckJs.ts, 10, 1))
>MyMap : Symbol(MyMap, Decl(extendingCollectionsWithCheckJs.js, 10, 1))
>Map : Symbol(Map, Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.iterable.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))

constructor() {
Expand All @@ -32,11 +32,12 @@ class MyMap extends Map {
}

class MyWeakMap extends WeakMap {
>MyWeakMap : Symbol(MyWeakMap, Decl(extendingSetWithCheckJs.ts, 16, 1))
>MyWeakMap : Symbol(MyWeakMap, Decl(extendingCollectionsWithCheckJs.js, 16, 1))
>WeakMap : Symbol(WeakMap, Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.iterable.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))

constructor() {
super();
>super : Symbol(WeakMapConstructor, Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.iterable.d.ts, --, --))
}
}

5 changes: 3 additions & 2 deletions ...s/reference/extendingSetWithCheckJs.types → ...nce/extendingCollectionsWithCheckJs.types
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,6 +1,6 @@
//// [tests/cases/compiler/extendingSetWithCheckJs.ts] ////
//// [tests/cases/compiler/extendingCollectionsWithCheckJs.ts] ////

=== extendingSetWithCheckJs.ts ===
=== extendingCollectionsWithCheckJs.js ===
class MySet extends Set {
>MySet : MySet
> : ^^^^^
Expand Down Expand Up @@ -60,3 +60,4 @@ class MyWeakMap extends WeakMap {
> : ^^^^^^^^^^^^^^^^^^
}
}

1 change: 1 addition & 0 deletions tests/baselines/reference/newMap.errors.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -5,4 +5,5 @@ newMap.ts(1,9): error TS2743: No overload expects 1 type arguments, but overload
new Map<string>();
~~~~~~
!!! error TS2743: No overload expects 1 type arguments, but overloads do exist that expect either 0 or 2 type arguments.
new WeakMap<object>();

2 changes: 2 additions & 0 deletions tests/baselines/reference/newMap.js
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2,8 +2,10 @@

//// [newMap.ts]
new Map<string>();
new WeakMap<object>();


//// [newMap.js]
"use strict";
new Map();
new WeakMap();
3 changes: 3 additions & 0 deletions tests/baselines/reference/newMap.symbols
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4,3 +4,6 @@
new Map<string>();
>Map : Symbol(Map, Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.iterable.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))

new WeakMap<object>();
>WeakMap : Symbol(WeakMap, Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.iterable.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))

6 changes: 6 additions & 0 deletions tests/baselines/reference/newMap.types
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7,3 +7,9 @@ new Map<string>();
>Map : MapConstructor
> : ^^^^^^^^^^^^^^

new WeakMap<object>();
>new WeakMap<object>() : WeakMap<object, any>
> : ^^^^^^^^^^^^^^^^^^^^
>WeakMap : WeakMapConstructor
> : ^^^^^^^^^^^^^^^^^^

3 changes: 2 additions & 1 deletion ...cases/compiler/extendingSetWithCheckJs.ts → ...mpiler/extendingCollectionsWithCheckJs.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,7 @@
// @noEmit: true
// @lib: es2017

// @filename: extendingCollectionsWithCheckJs.js
class MySet extends Set {
constructor() {
super();
Expand All @@ -26,4 +27,4 @@ class MyWeakMap extends WeakMap {
constructor() {
super();
}
}
}
1 change: 1 addition & 0 deletions tests/cases/compiler/newMap.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,3 +1,4 @@
// @target: es2015
// @lib: es6
new Map<string>();
new WeakMap<object>();