Re-add concat overload to support inferring tuples

Author: sandersn

src/lib/es5.d.ts

@@ -1108,6 +1108,11 @@ interface Array<T> {
       * Removes the last element from an array and returns it.
       */
     pop(): T | undefined;
+    /**
+      * Combines two or more arrays.
+      * @param items Additional items to add to the end of array1.
+      */
+    concat(...items: T[][]): T[];
     /**
       * Combines two or more arrays.
       * @param items Additional items to add to the end of array1.

tests/baselines/reference/concatTuples.js

@@ -0,0 +1,8 @@
+//// [concatTuples.ts]
+let ijs: [number, number][] = [[1, 2]];
+ijs = ijs.concat([[3, 4], [5, 6]]);
+
+
+//// [concatTuples.js]
+var ijs = [[1, 2]];
+ijs = ijs.concat([[3, 4], [5, 6]]);

tests/baselines/reference/concatTuples.symbols

@@ -0,0 +1,10 @@
+=== tests/cases/compiler/concatTuples.ts ===
+let ijs: [number, number][] = [[1, 2]];
+>ijs : Symbol(ijs, Decl(concatTuples.ts, 0, 3))
+
+ijs = ijs.concat([[3, 4], [5, 6]]);
+>ijs : Symbol(ijs, Decl(concatTuples.ts, 0, 3))
+>ijs.concat : Symbol(Array.concat, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+>ijs : Symbol(ijs, Decl(concatTuples.ts, 0, 3))
+>concat : Symbol(Array.concat, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+

tests/baselines/reference/concatTuples.types

@@ -0,0 +1,23 @@
+=== tests/cases/compiler/concatTuples.ts ===
+let ijs: [number, number][] = [[1, 2]];
+>ijs : [number, number][]
+>[[1, 2]] : [number, number][]
+>[1, 2] : [number, number]
+>1 : number
+>2 : number
+
+ijs = ijs.concat([[3, 4], [5, 6]]);
+>ijs = ijs.concat([[3, 4], [5, 6]]) : [number, number][]
+>ijs : [number, number][]
+>ijs.concat([[3, 4], [5, 6]]) : [number, number][]
+>ijs.concat : { (...items: [number, number][][]): [number, number][]; (...items: ([number, number] | [number, number][])[]): [number, number][]; }
+>ijs : [number, number][]
+>concat : { (...items: [number, number][][]): [number, number][]; (...items: ([number, number] | [number, number][])[]): [number, number][]; }
+>[[3, 4], [5, 6]] : [number, number][]
+>[3, 4] : [number, number]
+>3 : number
+>4 : number
+>[5, 6] : [number, number]
+>5 : number
+>6 : number
+

tests/cases/compiler/concatTuples.ts

@@ -0,0 +1,2 @@
+let ijs: [number, number][] = [[1, 2]];
+ijs = ijs.concat([[3, 4], [5, 6]]);