Adding test for emit of metadata for string literal union

Author: sheetalkamat

tests/baselines/reference/metadataOfStringLiteral.js

@@ -0,0 +1,28 @@
+//// [metadataOfStringLiteral.ts]
+function PropDeco(target: Object, propKey: string | symbol) { }
+
+class Foo {
+    @PropDeco
+    public foo: "foo" | "bar";
+}
+
+//// [metadataOfStringLiteral.js]
+var __decorate = (this && this.__decorate) || function (decorators, target, key, desc) {
+    var c = arguments.length, r = c < 3 ? target : desc === null ? desc = Object.getOwnPropertyDescriptor(target, key) : desc, d;
+    if (typeof Reflect === "object" && typeof Reflect.decorate === "function") r = Reflect.decorate(decorators, target, key, desc);
+    else for (var i = decorators.length - 1; i >= 0; i--) if (d = decorators[i]) r = (c < 3 ? d(r) : c > 3 ? d(target, key, r) : d(target, key)) || r;
+    return c > 3 && r && Object.defineProperty(target, key, r), r;
+};
+var __metadata = (this && this.__metadata) || function (k, v) {
+    if (typeof Reflect === "object" && typeof Reflect.metadata === "function") return Reflect.metadata(k, v);
+};
+function PropDeco(target, propKey) { }
+var Foo = (function () {
+    function Foo() {
+    }
+    return Foo;
+}());
+__decorate([
+    PropDeco,
+    __metadata("design:type", Object)
+], Foo.prototype, "foo");

tests/baselines/reference/metadataOfStringLiteral.symbols

@@ -0,0 +1,16 @@
+=== tests/cases/compiler/metadataOfStringLiteral.ts ===
+function PropDeco(target: Object, propKey: string | symbol) { }
+>PropDeco : Symbol(PropDeco, Decl(metadataOfStringLiteral.ts, 0, 0))
+>target : Symbol(target, Decl(metadataOfStringLiteral.ts, 0, 18))
+>Object : Symbol(Object, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
+>propKey : Symbol(propKey, Decl(metadataOfStringLiteral.ts, 0, 33))
+
+class Foo {
+>Foo : Symbol(Foo, Decl(metadataOfStringLiteral.ts, 0, 63))
+
+    @PropDeco
+>PropDeco : Symbol(PropDeco, Decl(metadataOfStringLiteral.ts, 0, 0))
+
+    public foo: "foo" | "bar";
+>foo : Symbol(Foo.foo, Decl(metadataOfStringLiteral.ts, 2, 11))
+}

tests/baselines/reference/metadataOfStringLiteral.types

@@ -0,0 +1,16 @@
+=== tests/cases/compiler/metadataOfStringLiteral.ts ===
+function PropDeco(target: Object, propKey: string | symbol) { }
+>PropDeco : (target: Object, propKey: string | symbol) => void
+>target : Object
+>Object : Object
+>propKey : string | symbol
+
+class Foo {
+>Foo : Foo
+
+    @PropDeco
+>PropDeco : (target: Object, propKey: string | symbol) => void
+
+    public foo: "foo" | "bar";
+>foo : "foo" | "bar"
+}

tests/cases/compiler/metadataOfStringLiteral.ts

@@ -0,0 +1,8 @@
+// @experimentalDecorators: true
+// @emitDecoratorMetadata: true
+function PropDeco(target: Object, propKey: string | symbol) { }
+
+class Foo {
+    @PropDeco
+    public foo: "foo" | "bar";
+}