Add proposal-upsert methods to lib.esnext.collection (#62612)

Co-authored-by: Jake Bailey <5341706+jakebailey@users.noreply.github.com>

Author: Renegade334

src/compiler/commandLineParser.ts

@@ -245,12 +245,12 @@ const libEntries: [string, string][] = [
     ["esnext.object", "lib.es2024.object.d.ts"],
     ["esnext.regexp", "lib.es2024.regexp.d.ts"],
     ["esnext.string", "lib.es2024.string.d.ts"],
-    ["esnext.collection", "lib.es2025.collection.d.ts"],
     ["esnext.float16", "lib.es2025.float16.d.ts"],
     ["esnext.iterator", "lib.es2025.iterator.d.ts"],
     ["esnext.promise", "lib.es2025.promise.d.ts"],
     // ESNext By-feature options
     ["esnext.array", "lib.esnext.array.d.ts"],
+    ["esnext.collection", "lib.esnext.collection.d.ts"],
     ["esnext.decorators", "lib.esnext.decorators.d.ts"],
     ["esnext.disposable", "lib.esnext.disposable.d.ts"],
     ["esnext.error", "lib.esnext.error.d.ts"],

src/compiler/utilities.ts

@@ -1580,6 +1580,10 @@ export const getScriptTargetFeatures: () => ScriptTargetFeatures = /* @__PURE__
                 "keys",
                 "values",
             ],
+            esnext: [
+                "getOrInsert",
+                "getOrInsertComputed",
+            ],
         })),
         MapConstructor: new Map(Object.entries({
             es2024: [
@@ -1637,6 +1641,10 @@ export const getScriptTargetFeatures: () => ScriptTargetFeatures = /* @__PURE__
                 "keys",
                 "values",
             ],
+            esnext: [
+                "getOrInsert",
+                "getOrInsertComputed",
+            ],
         })),
         WeakSet: new Map(Object.entries({
             es2015: [

src/lib/esnext.collection.d.ts

@@ -0,0 +1,31 @@
+/// <reference lib="es2025.collection" />
+
+interface Map<K, V> {
+    /**
+     * Returns a specified element from the Map object.
+     * If no element is associated with the specified key, a new element with the value `defaultValue` will be inserted into the Map and returned.
+     * @returns The element associated with the specified key, which will be `defaultValue` if no element previously existed.
+     */
+    getOrInsert(key: K, defaultValue: V): V;
+    /**
+     * Returns a specified element from the Map object.
+     * If no element is associated with the specified key, the result of passing the specified key to the `callback` function will be inserted into the Map and returned.
+     * @returns The element associated with the specific key, which will be the newly computed value if no element previously existed.
+     */
+    getOrInsertComputed(key: K, callback: (key: K) => V): V;
+}
+
+interface WeakMap<K extends WeakKey, V> {
+    /**
+     * Returns a specified element from the WeakMap object.
+     * If no element is associated with the specified key, a new element with the value `defaultValue` will be inserted into the WeakMap and returned.
+     * @returns The element associated with the specified key, which will be `defaultValue` if no element previously existed.
+     */
+    getOrInsert(key: K, defaultValue: V): V;
+    /**
+     * Returns a specified element from the WeakMap object.
+     * If no element is associated with the specified key, the result of passing the specified key to the `callback` function will be inserted into the WeakMap and returned.
+     * @returns The element associated with the specific key, which will be the newly computed value if no element previously existed.
+     */
+    getOrInsertComputed(key: K, callback: (key: K) => V): V;
+}

src/lib/esnext.d.ts

@@ -1,5 +1,6 @@
 /// <reference lib="es2025" />
 /// <reference lib="esnext.intl" />
+/// <reference lib="esnext.collection" />
 /// <reference lib="esnext.decorators" />
 /// <reference lib="esnext.disposable" />
 /// <reference lib="esnext.array" />

src/lib/libs.json

@@ -87,6 +87,7 @@
         "es2025.promise",
         "es2025.regexp",
         "esnext.array",
+        "esnext.collection",
         "esnext.decorators",
         "esnext.disposable",
         "esnext.error",

tests/baselines/reference/acceptSymbolAsWeakType.symbols

@@ -30,7 +30,7 @@ ws.delete(s);
 
 const wm = new WeakMap([[s, false]]);
 >wm : Symbol(wm, Decl(acceptSymbolAsWeakType.ts, 7, 5))
->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, --, --))
+>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, --, --), Decl(lib.esnext.collection.d.ts, --, --))
 >s : Symbol(s, Decl(acceptSymbolAsWeakType.ts, 0, 5))
 
 wm.set(s, true);

tests/baselines/reference/awaitUsingDeclarationsWithIteratorObject.symbols

@@ -55,7 +55,7 @@ async function f() {
     await using it5 = new Map<string, string>().entries();
 >it5 : Symbol(it5, Decl(awaitUsingDeclarationsWithIteratorObject.ts, 15, 15))
 >new Map<string, string>().entries : Symbol(Map.entries, Decl(lib.es2015.iterable.d.ts, --, --))
->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, --, --))
+>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, --, --), Decl(lib.esnext.collection.d.ts, --, --))
 >entries : Symbol(Map.entries, Decl(lib.es2015.iterable.d.ts, --, --))
 
     await using it6 = new Set<string>().keys();

tests/baselines/reference/builtinIteratorReturn(strictbuiltiniteratorreturn=false).symbols

@@ -6,7 +6,7 @@ declare const array: number[];
 
 declare const map: Map<string, number>;
 >map : Symbol(map, Decl(builtinIteratorReturn.ts, 1, 13))
->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, --, --))
+>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, --, --), Decl(lib.esnext.collection.d.ts, --, --))
 
 declare const set: Set<number>;
 >set : Symbol(set, Decl(builtinIteratorReturn.ts, 2, 13))

tests/baselines/reference/builtinIteratorReturn(strictbuiltiniteratorreturn=true).symbols

@@ -6,7 +6,7 @@ declare const array: number[];
 
 declare const map: Map<string, number>;
 >map : Symbol(map, Decl(builtinIteratorReturn.ts, 1, 13))
->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, --, --))
+>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, --, --), Decl(lib.esnext.collection.d.ts, --, --))
 
 declare const set: Set<number>;
 >set : Symbol(set, Decl(builtinIteratorReturn.ts, 2, 13))