ES5:Emit parameter initialiser before object rest destructuring

Fix #14026, where ES5 emit for a parameter with

1. a default value initialiser
2. an object binding pattern containing an object rest

incorrectly emitted the destructuring for the object rest before the
default value initialisation.

This happened because, during emit, the ES next transform runs first,
transforming object rest destructuring and marking it as part of the
function prologue. Then the ES5 transform runs and transforms the
default initialiser, also marking it as part of the prologue. Then the
prologue is emitted in the order the statements were added.

The fix is to not mark the object rest destructuring as part of the
prologue. I'm not 100% sure that this is the right fix, but it fixes the
bug as it stands today.

Here's an example:

```ts
function foobar({ bar={}, ...opts }: any = {}) { }
```

which should have the ES5 emit:

```js
function foobar(_a) {
  if (_a === void 0) { _a = {}; }
  var _b = _a.bar, bar = _b === void 0 ? {} : _b, opts = __rest(_a, ["bar"]);
}
```

src/compiler/transformers/esnext.ts

@@ -375,7 +375,6 @@ namespace ts {
                                 declarations
                             )
                         );
-                        setEmitFlags(statement, EmitFlags.CustomPrologue);
                         leadingStatements = append(leadingStatements, statement);
                     }
                 }

tests/baselines/reference/objectRestParameter.js

@@ -14,7 +14,11 @@ class C {
         // actually, never mind, don't clone
     }
 }
-
+function foobar({ bar={}, ...opts }: any = {}) {
+}
+foobar();
+foobar({ baz: 'hello' });
+foobar({ bar: { greeting: 'hello' } });
 
 
 //// [objectRestParameter.js]
@@ -48,3 +52,9 @@ class C {
         // actually, never mind, don't clone
     }
 }
+function foobar(_a = {}) {
+    var { bar = {} } = _a, opts = __rest(_a, ["bar"]);
+}
+foobar();
+foobar({ baz: 'hello' });
+foobar({ bar: { greeting: 'hello' } });

tests/baselines/reference/objectRestParameter.symbols

@@ -64,5 +64,20 @@ class C {
         // actually, never mind, don't clone
     }
 }
+function foobar({ bar={}, ...opts }: any = {}) {
+>foobar : Symbol(foobar, Decl(objectRestParameter.ts, 14, 1))
+>bar : Symbol(bar, Decl(objectRestParameter.ts, 15, 17))
+>opts : Symbol(opts, Decl(objectRestParameter.ts, 15, 25))
+}
+foobar();
+>foobar : Symbol(foobar, Decl(objectRestParameter.ts, 14, 1))
 
+foobar({ baz: 'hello' });
+>foobar : Symbol(foobar, Decl(objectRestParameter.ts, 14, 1))
+>baz : Symbol(baz, Decl(objectRestParameter.ts, 18, 8))
+
+foobar({ bar: { greeting: 'hello' } });
+>foobar : Symbol(foobar, Decl(objectRestParameter.ts, 14, 1))
+>bar : Symbol(bar, Decl(objectRestParameter.ts, 19, 8))
+>greeting : Symbol(greeting, Decl(objectRestParameter.ts, 19, 15))
 

tests/baselines/reference/objectRestParameter.types

@@ -75,5 +75,30 @@ class C {
         // actually, never mind, don't clone
     }
 }
+function foobar({ bar={}, ...opts }: any = {}) {
+>foobar : ({bar, ...opts}?: any) => void
+>bar : {}
+>{} : {}
+>opts : any
+>{} : {}
+}
+foobar();
+>foobar() : void
+>foobar : ({bar, ...opts}?: any) => void
 
+foobar({ baz: 'hello' });
+>foobar({ baz: 'hello' }) : void
+>foobar : ({bar, ...opts}?: any) => void
+>{ baz: 'hello' } : { baz: string; }
+>baz : string
+>'hello' : "hello"
+
+foobar({ bar: { greeting: 'hello' } });
+>foobar({ bar: { greeting: 'hello' } }) : void
+>foobar : ({bar, ...opts}?: any) => void
+>{ bar: { greeting: 'hello' } } : { bar: { greeting: string; }; }
+>bar : { greeting: string; }
+>{ greeting: 'hello' } : { greeting: string; }
+>greeting : string
+>'hello' : "hello"
 

tests/baselines/reference/objectRestParameterES5.js

@@ -0,0 +1,69 @@
+//// [objectRestParameterES5.ts]
+function cloneAgain({ a, ...clone }: { a: number, b: string }): void {
+}
+
+declare function suddenly(f: (a: { x: { z, ka }, y: string }) => void);
+suddenly(({ x: a, ...rest }) => rest.y);
+suddenly(({ x: { z = 12, ...nested }, ...rest } = { x: { z: 1, ka: 1 }, y: 'noo' }) => rest.y + nested.ka);
+
+class C {
+    m({ a, ...clone }: { a: number, b: string}): void {
+        // actually, never mind, don't clone
+    }
+    set p({ a, ...clone }: { a: number, b: string}) {
+        // actually, never mind, don't clone
+    }
+}
+function foobar({ bar={}, ...opts }: any = {}) {
+}
+foobar();
+foobar({ baz: 'hello' });
+foobar({ bar: { greeting: 'hello' } });
+
+
+//// [objectRestParameterES5.js]
+var __rest = (this && this.__rest) || function (s, e) {
+    var t = {};
+    for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p) && e.indexOf(p) < 0)
+        t[p] = s[p];
+    if (s != null && typeof Object.getOwnPropertySymbols === "function")
+        for (var i = 0, p = Object.getOwnPropertySymbols(s); i < p.length; i++) if (e.indexOf(p[i]) < 0)
+            t[p[i]] = s[p[i]];
+    return t;
+};
+function cloneAgain(_a) {
+    var a = _a.a, clone = __rest(_a, ["a"]);
+}
+suddenly(function (_a) {
+    var a = _a.x, rest = __rest(_a, ["x"]);
+    return rest.y;
+});
+suddenly(function (_a) {
+    if (_a === void 0) { _a = { x: { z: 1, ka: 1 }, y: 'noo' }; }
+    var _b = _a.x, _c = _b.z, z = _c === void 0 ? 12 : _c, nested = __rest(_b, ["z"]), rest = __rest(_a, ["x"]);
+    return rest.y + nested.ka;
+});
+var C = (function () {
+    function C() {
+    }
+    C.prototype.m = function (_a) {
+        var a = _a.a, clone = __rest(_a, ["a"]);
+        // actually, never mind, don't clone
+    };
+    Object.defineProperty(C.prototype, "p", {
+        set: function (_a) {
+            var a = _a.a, clone = __rest(_a, ["a"]);
+            // actually, never mind, don't clone
+        },
+        enumerable: true,
+        configurable: true
+    });
+    return C;
+}());
+function foobar(_a) {
+    if (_a === void 0) { _a = {}; }
+    var _b = _a.bar, bar = _b === void 0 ? {} : _b, opts = __rest(_a, ["bar"]);
+}
+foobar();
+foobar({ baz: 'hello' });
+foobar({ bar: { greeting: 'hello' } });

tests/baselines/reference/objectRestParameterES5.symbols

@@ -0,0 +1,83 @@
+=== tests/cases/conformance/types/rest/objectRestParameterES5.ts ===
+function cloneAgain({ a, ...clone }: { a: number, b: string }): void {
+>cloneAgain : Symbol(cloneAgain, Decl(objectRestParameterES5.ts, 0, 0))
+>a : Symbol(a, Decl(objectRestParameterES5.ts, 0, 21))
+>clone : Symbol(clone, Decl(objectRestParameterES5.ts, 0, 24))
+>a : Symbol(a, Decl(objectRestParameterES5.ts, 0, 38))
+>b : Symbol(b, Decl(objectRestParameterES5.ts, 0, 49))
+}
+
+declare function suddenly(f: (a: { x: { z, ka }, y: string }) => void);
+>suddenly : Symbol(suddenly, Decl(objectRestParameterES5.ts, 1, 1))
+>f : Symbol(f, Decl(objectRestParameterES5.ts, 3, 26))
+>a : Symbol(a, Decl(objectRestParameterES5.ts, 3, 30))
+>x : Symbol(x, Decl(objectRestParameterES5.ts, 3, 34))
+>z : Symbol(z, Decl(objectRestParameterES5.ts, 3, 39))
+>ka : Symbol(ka, Decl(objectRestParameterES5.ts, 3, 42))
+>y : Symbol(y, Decl(objectRestParameterES5.ts, 3, 48))
+
+suddenly(({ x: a, ...rest }) => rest.y);
+>suddenly : Symbol(suddenly, Decl(objectRestParameterES5.ts, 1, 1))
+>x : Symbol(x, Decl(objectRestParameterES5.ts, 3, 34))
+>a : Symbol(a, Decl(objectRestParameterES5.ts, 4, 11))
+>rest : Symbol(rest, Decl(objectRestParameterES5.ts, 4, 17))
+>rest.y : Symbol(y, Decl(objectRestParameterES5.ts, 3, 48))
+>rest : Symbol(rest, Decl(objectRestParameterES5.ts, 4, 17))
+>y : Symbol(y, Decl(objectRestParameterES5.ts, 3, 48))
+
+suddenly(({ x: { z = 12, ...nested }, ...rest } = { x: { z: 1, ka: 1 }, y: 'noo' }) => rest.y + nested.ka);
+>suddenly : Symbol(suddenly, Decl(objectRestParameterES5.ts, 1, 1))
+>x : Symbol(x, Decl(objectRestParameterES5.ts, 3, 34))
+>z : Symbol(z, Decl(objectRestParameterES5.ts, 5, 16))
+>nested : Symbol(nested, Decl(objectRestParameterES5.ts, 5, 24))
+>rest : Symbol(rest, Decl(objectRestParameterES5.ts, 5, 37))
+>x : Symbol(x, Decl(objectRestParameterES5.ts, 5, 51))
+>z : Symbol(z, Decl(objectRestParameterES5.ts, 5, 56))
+>ka : Symbol(ka, Decl(objectRestParameterES5.ts, 5, 62))
+>y : Symbol(y, Decl(objectRestParameterES5.ts, 5, 71))
+>rest.y : Symbol(y, Decl(objectRestParameterES5.ts, 3, 48))
+>rest : Symbol(rest, Decl(objectRestParameterES5.ts, 5, 37))
+>y : Symbol(y, Decl(objectRestParameterES5.ts, 3, 48))
+>nested.ka : Symbol(ka, Decl(objectRestParameterES5.ts, 3, 42))
+>nested : Symbol(nested, Decl(objectRestParameterES5.ts, 5, 24))
+>ka : Symbol(ka, Decl(objectRestParameterES5.ts, 3, 42))
+
+class C {
+>C : Symbol(C, Decl(objectRestParameterES5.ts, 5, 107))
+
+    m({ a, ...clone }: { a: number, b: string}): void {
+>m : Symbol(C.m, Decl(objectRestParameterES5.ts, 7, 9))
+>a : Symbol(a, Decl(objectRestParameterES5.ts, 8, 7))
+>clone : Symbol(clone, Decl(objectRestParameterES5.ts, 8, 10))
+>a : Symbol(a, Decl(objectRestParameterES5.ts, 8, 24))
+>b : Symbol(b, Decl(objectRestParameterES5.ts, 8, 35))
+
+        // actually, never mind, don't clone
+    }
+    set p({ a, ...clone }: { a: number, b: string}) {
+>p : Symbol(C.p, Decl(objectRestParameterES5.ts, 10, 5))
+>a : Symbol(a, Decl(objectRestParameterES5.ts, 11, 11))
+>clone : Symbol(clone, Decl(objectRestParameterES5.ts, 11, 14))
+>a : Symbol(a, Decl(objectRestParameterES5.ts, 11, 28))
+>b : Symbol(b, Decl(objectRestParameterES5.ts, 11, 39))
+
+        // actually, never mind, don't clone
+    }
+}
+function foobar({ bar={}, ...opts }: any = {}) {
+>foobar : Symbol(foobar, Decl(objectRestParameterES5.ts, 14, 1))
+>bar : Symbol(bar, Decl(objectRestParameterES5.ts, 15, 17))
+>opts : Symbol(opts, Decl(objectRestParameterES5.ts, 15, 25))
+}
+foobar();
+>foobar : Symbol(foobar, Decl(objectRestParameterES5.ts, 14, 1))
+
+foobar({ baz: 'hello' });
+>foobar : Symbol(foobar, Decl(objectRestParameterES5.ts, 14, 1))
+>baz : Symbol(baz, Decl(objectRestParameterES5.ts, 18, 8))
+
+foobar({ bar: { greeting: 'hello' } });
+>foobar : Symbol(foobar, Decl(objectRestParameterES5.ts, 14, 1))
+>bar : Symbol(bar, Decl(objectRestParameterES5.ts, 19, 8))
+>greeting : Symbol(greeting, Decl(objectRestParameterES5.ts, 19, 15))
+

tests/baselines/reference/objectRestParameterES5.types

@@ -0,0 +1,104 @@
+=== tests/cases/conformance/types/rest/objectRestParameterES5.ts ===
+function cloneAgain({ a, ...clone }: { a: number, b: string }): void {
+>cloneAgain : ({a, ...clone}: { a: number; b: string; }) => void
+>a : number
+>clone : { b: string; }
+>a : number
+>b : string
+}
+
+declare function suddenly(f: (a: { x: { z, ka }, y: string }) => void);
+>suddenly : (f: (a: { x: { z: any; ka: any; }; y: string; }) => void) => any
+>f : (a: { x: { z: any; ka: any; }; y: string; }) => void
+>a : { x: { z: any; ka: any; }; y: string; }
+>x : { z: any; ka: any; }
+>z : any
+>ka : any
+>y : string
+
+suddenly(({ x: a, ...rest }) => rest.y);
+>suddenly(({ x: a, ...rest }) => rest.y) : any
+>suddenly : (f: (a: { x: { z: any; ka: any; }; y: string; }) => void) => any
+>({ x: a, ...rest }) => rest.y : ({x: a, ...rest}: { x: { z: any; ka: any; }; y: string; }) => string
+>x : any
+>a : { z: any; ka: any; }
+>rest : { y: string; }
+>rest.y : string
+>rest : { y: string; }
+>y : string
+
+suddenly(({ x: { z = 12, ...nested }, ...rest } = { x: { z: 1, ka: 1 }, y: 'noo' }) => rest.y + nested.ka);
+>suddenly(({ x: { z = 12, ...nested }, ...rest } = { x: { z: 1, ka: 1 }, y: 'noo' }) => rest.y + nested.ka) : any
+>suddenly : (f: (a: { x: { z: any; ka: any; }; y: string; }) => void) => any
+>({ x: { z = 12, ...nested }, ...rest } = { x: { z: 1, ka: 1 }, y: 'noo' }) => rest.y + nested.ka : ({x: {z, ...nested}, ...rest}?: { x: { z: any; ka: any; }; y: string; }) => string
+>x : any
+>z : any
+>12 : 12
+>nested : { ka: any; }
+>rest : { y: string; }
+>{ x: { z: 1, ka: 1 }, y: 'noo' } : { x: { z: number; ka: number; }; y: string; }
+>x : { z: number; ka: number; }
+>{ z: 1, ka: 1 } : { z: number; ka: number; }
+>z : number
+>1 : 1
+>ka : number
+>1 : 1
+>y : string
+>'noo' : "noo"
+>rest.y + nested.ka : string
+>rest.y : string
+>rest : { y: string; }
+>y : string
+>nested.ka : any
+>nested : { ka: any; }
+>ka : any
+
+class C {
+>C : C
+
+    m({ a, ...clone }: { a: number, b: string}): void {
+>m : ({a, ...clone}: { a: number; b: string; }) => void
+>a : number
+>clone : { b: string; }
+>a : number
+>b : string
+
+        // actually, never mind, don't clone
+    }
+    set p({ a, ...clone }: { a: number, b: string}) {
+>p : { a: number; b: string; }
+>a : number
+>clone : { b: string; }
+>a : number
+>b : string
+
+        // actually, never mind, don't clone
+    }
+}
+function foobar({ bar={}, ...opts }: any = {}) {
+>foobar : ({bar, ...opts}?: any) => void
+>bar : {}
+>{} : {}
+>opts : any
+>{} : {}
+}
+foobar();
+>foobar() : void
+>foobar : ({bar, ...opts}?: any) => void
+
+foobar({ baz: 'hello' });
+>foobar({ baz: 'hello' }) : void
+>foobar : ({bar, ...opts}?: any) => void
+>{ baz: 'hello' } : { baz: string; }
+>baz : string
+>'hello' : "hello"
+
+foobar({ bar: { greeting: 'hello' } });
+>foobar({ bar: { greeting: 'hello' } }) : void
+>foobar : ({bar, ...opts}?: any) => void
+>{ bar: { greeting: 'hello' } } : { bar: { greeting: string; }; }
+>bar : { greeting: string; }
+>{ greeting: 'hello' } : { greeting: string; }
+>greeting : string
+>'hello' : "hello"
+

tests/cases/conformance/types/rest/objectRestParameter.ts

@@ -14,4 +14,8 @@ class C {
         // actually, never mind, don't clone
     }
 }
-
+function foobar({ bar={}, ...opts }: any = {}) {
+}
+foobar();
+foobar({ baz: 'hello' });
+foobar({ bar: { greeting: 'hello' } });

tests/cases/conformance/types/rest/objectRestParameterES5.ts

@@ -0,0 +1,21 @@
+// @target: es5
+function cloneAgain({ a, ...clone }: { a: number, b: string }): void {
+}
+
+declare function suddenly(f: (a: { x: { z, ka }, y: string }) => void);
+suddenly(({ x: a, ...rest }) => rest.y);
+suddenly(({ x: { z = 12, ...nested }, ...rest } = { x: { z: 1, ka: 1 }, y: 'noo' }) => rest.y + nested.ka);
+
+class C {
+    m({ a, ...clone }: { a: number, b: string}): void {
+        // actually, never mind, don't clone
+    }
+    set p({ a, ...clone }: { a: number, b: string}) {
+        // actually, never mind, don't clone
+    }
+}
+function foobar({ bar={}, ...opts }: any = {}) {
+}
+foobar();
+foobar({ baz: 'hello' });
+foobar({ bar: { greeting: 'hello' } });