From 027d65a92031ac49036f456458702165c8b78554 Mon Sep 17 00:00:00 2001
From: Sheetal Nandi <shkamat@microsoft.com>
Date: Wed, 13 Mar 2019 14:52:13 -0700
Subject: [PATCH] Fix map constructor to accept readonly tuple Fixes #29721

---
 src/lib/es2015.collection.d.ts                  |  2 +-
 src/lib/es2015.iterable.d.ts                    |  2 +-
 .../reference/mapConstructorOnReadonlyTuple.js  |  7 +++++++
 .../mapConstructorOnReadonlyTuple.symbols       |  8 ++++++++
 .../mapConstructorOnReadonlyTuple.types         | 17 +++++++++++++++++
 .../compiler/mapConstructorOnReadonlyTuple.ts   |  4 ++++
 6 files changed, 38 insertions(+), 2 deletions(-)
 create mode 100644 tests/baselines/reference/mapConstructorOnReadonlyTuple.js
 create mode 100644 tests/baselines/reference/mapConstructorOnReadonlyTuple.symbols
 create mode 100644 tests/baselines/reference/mapConstructorOnReadonlyTuple.types
 create mode 100644 tests/cases/compiler/mapConstructorOnReadonlyTuple.ts

diff --git a/src/lib/es2015.collection.d.ts b/src/lib/es2015.collection.d.ts
index 34afa3d1b2b..4f293f0f6c3 100644
--- a/src/lib/es2015.collection.d.ts
+++ b/src/lib/es2015.collection.d.ts
@@ -10,7 +10,7 @@ interface Map<K, V> {
 
 interface MapConstructor {
     new(): Map<any, any>;
-    new<K, V>(entries?: ReadonlyArray<[K, V]> | null): Map<K, V>;
+    new<K, V>(entries?: ReadonlyArray<readonly [K, V]> | null): Map<K, V>;
     readonly prototype: Map<any, any>;
 }
 declare var Map: MapConstructor;
diff --git a/src/lib/es2015.iterable.d.ts b/src/lib/es2015.iterable.d.ts
index f0a38dff3fe..b679bea14d5 100644
--- a/src/lib/es2015.iterable.d.ts
+++ b/src/lib/es2015.iterable.d.ts
@@ -129,7 +129,7 @@ interface ReadonlyMap<K, V> {
 }
 
 interface MapConstructor {
-    new <K, V>(iterable: Iterable<[K, V]>): Map<K, V>;
+    new <K, V>(iterable: Iterable<readonly [K, V]>): Map<K, V>;
 }
 
 interface WeakMap<K extends object, V> { }
diff --git a/tests/baselines/reference/mapConstructorOnReadonlyTuple.js b/tests/baselines/reference/mapConstructorOnReadonlyTuple.js
new file mode 100644
index 00000000000..af2a3b20b4c
--- /dev/null
+++ b/tests/baselines/reference/mapConstructorOnReadonlyTuple.js
@@ -0,0 +1,7 @@
+//// [mapConstructorOnReadonlyTuple.ts]
+const pairs = [['1', 1], ['2', 2]] as const
+new Map(pairs);
+
+//// [mapConstructorOnReadonlyTuple.js]
+const pairs = [['1', 1], ['2', 2]];
+new Map(pairs);
diff --git a/tests/baselines/reference/mapConstructorOnReadonlyTuple.symbols b/tests/baselines/reference/mapConstructorOnReadonlyTuple.symbols
new file mode 100644
index 00000000000..8811f5b92db
--- /dev/null
+++ b/tests/baselines/reference/mapConstructorOnReadonlyTuple.symbols
@@ -0,0 +1,8 @@
+=== tests/cases/compiler/mapConstructorOnReadonlyTuple.ts ===
+const pairs = [['1', 1], ['2', 2]] as const
+>pairs : Symbol(pairs, Decl(mapConstructorOnReadonlyTuple.ts, 0, 5))
+
+new Map(pairs);
+>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, --, --))
+>pairs : Symbol(pairs, Decl(mapConstructorOnReadonlyTuple.ts, 0, 5))
+
diff --git a/tests/baselines/reference/mapConstructorOnReadonlyTuple.types b/tests/baselines/reference/mapConstructorOnReadonlyTuple.types
new file mode 100644
index 00000000000..44fc38fa797
--- /dev/null
+++ b/tests/baselines/reference/mapConstructorOnReadonlyTuple.types
@@ -0,0 +1,17 @@
+=== tests/cases/compiler/mapConstructorOnReadonlyTuple.ts ===
+const pairs = [['1', 1], ['2', 2]] as const
+>pairs : readonly [readonly ["1", 1], readonly ["2", 2]]
+>[['1', 1], ['2', 2]] as const : readonly [readonly ["1", 1], readonly ["2", 2]]
+>[['1', 1], ['2', 2]] : readonly [readonly ["1", 1], readonly ["2", 2]]
+>['1', 1] : readonly ["1", 1]
+>'1' : "1"
+>1 : 1
+>['2', 2] : readonly ["2", 2]
+>'2' : "2"
+>2 : 2
+
+new Map(pairs);
+>new Map(pairs) : Map<"1" | "2", 1 | 2>
+>Map : MapConstructor
+>pairs : readonly [readonly ["1", 1], readonly ["2", 2]]
+
diff --git a/tests/cases/compiler/mapConstructorOnReadonlyTuple.ts b/tests/cases/compiler/mapConstructorOnReadonlyTuple.ts
new file mode 100644
index 00000000000..f4914e67def
--- /dev/null
+++ b/tests/cases/compiler/mapConstructorOnReadonlyTuple.ts
@@ -0,0 +1,4 @@
+// @target: es2015
+
+const pairs = [['1', 1], ['2', 2]] as const
+new Map(pairs);
\ No newline at end of file