1 files changed, 53 insertions, 7 deletions
diff --git a/cli/tsc/dts/lib.esnext.collection.d.ts b/cli/tsc/dts/lib.esnext.collection.d.ts
index 834b1a6b1..1278a38f6 100644
--- a/cli/tsc/dts/lib.esnext.collection.d.ts
+++ b/cli/tsc/dts/lib.esnext.collection.d.ts
@@ -28,33 +28,79 @@ interface MapConstructor {
     ): Map<K, T[]>;
 }
 
+interface ReadonlySetLike<T> {
+    /**
+     * Despite its name, returns an iterator of the values in the set-like.
+     */
+    keys(): Iterator<T>;
+    /**
+     * @returns a boolean indicating whether an element with the specified value exists in the set-like or not.
+     */
+    has(value: T): boolean;
+    /**
+     * @returns the number of (unique) elements in the set-like.
+     */
+    readonly size: number;
+}
+
 interface Set<T> {
     /**
      * @returns a new Set containing all the elements in this Set and also all the elements in the argument.
      */
-    union<U>(other: Set<U>): Set<T | U>;
+    union<U>(other: ReadonlySetLike<U>): Set<T | U>;
+    /**
+     * @returns a new Set containing all the elements which are both in this Set and in the argument.
+     */
+    intersection<U>(other: ReadonlySetLike<U>): Set<T & U>;
+    /**
+     * @returns a new Set containing all the elements in this Set which are not also in the argument.
+     */
+    difference<U>(other: ReadonlySetLike<U>): Set<T>;
+    /**
+     * @returns a new Set containing all the elements which are in either this Set or in the argument, but not in both.
+     */
+    symmetricDifference<U>(other: ReadonlySetLike<U>): Set<T | U>;
+    /**
+     * @returns a boolean indicating whether all the elements in this Set are also in the argument.
+     */
+    isSubsetOf(other: ReadonlySetLike<unknown>): boolean;
+    /**
+     * @returns a boolean indicating whether all the elements in the argument are also in this Set.
+     */
+    isSupersetOf(other: ReadonlySetLike<unknown>): boolean;
+    /**
+     * @returns a boolean indicating whether this Set has no elements in common with the argument.
+     */
+    isDisjointFrom(other: ReadonlySetLike<unknown>): boolean;
+}
+
+interface ReadonlySet<T> {
+    /**
+     * @returns a new Set containing all the elements in this Set and also all the elements in the argument.
+     */
+    union<U>(other: ReadonlySetLike<U>): Set<T | U>;
     /**
      * @returns a new Set containing all the elements which are both in this Set and in the argument.
      */
-    intersection<U>(other: Set<U>): Set<T & U>;
+    intersection<U>(other: ReadonlySetLike<U>): Set<T & U>;
     /**
      * @returns a new Set containing all the elements in this Set which are not also in the argument.
      */
-    difference<U>(other: Set<U>): Set<T>;
+    difference<U>(other: ReadonlySetLike<U>): Set<T>;
     /**
      * @returns a new Set containing all the elements which are in either this Set or in the argument, but not in both.
      */
-    symmetricDifference<U>(other: Set<U>): Set<T | U>;
+    symmetricDifference<U>(other: ReadonlySetLike<U>): Set<T | U>;
     /**
      * @returns a boolean indicating whether all the elements in this Set are also in the argument.
      */
-    isSubsetOf(other: Set<unknown>): boolean;
+    isSubsetOf(other: ReadonlySetLike<unknown>): boolean;
     /**
      * @returns a boolean indicating whether all the elements in the argument are also in this Set.
      */
-    isSupersetOf(other: Set<unknown>): boolean;
+    isSupersetOf(other: ReadonlySetLike<unknown>): boolean;
     /**
      * @returns a boolean indicating whether this Set has no elements in common with the argument.
      */
-    isDisjointFrom(other: Set<unknown>): boolean;
+    isDisjointFrom(other: ReadonlySetLike<unknown>): boolean;
 }