fix parameter initializer referencing identifier declared after it

src/compiler/checker.ts

@@ -25400,16 +25400,18 @@ namespace ts {
             visit(node.initializer!);
 
             function visit(n: Node): void {
-                if (isTypeNode(n) || isDeclarationName(n)) {
+                if (isTypeNode(n)) {
                     // do not dive in types
-                    // skip declaration names (i.e. in object literal expressions)
                     return;
                 }
                 if (n.kind === SyntaxKind.PropertyAccessExpression) {
                     // skip property names in property access expression
                     return visit((<PropertyAccessExpression>n).expression);
                 }
                 else if (n.kind === SyntaxKind.Identifier) {
+                    if (isDeclarationName(n) && n.parent.kind !== SyntaxKind.ShorthandPropertyAssignment) {
+                        return;
+                    }
                     // check FunctionLikeDeclaration.locals (stores parameters\function local variable)
                     // if it contains entry with a specified name
                     const symbol = resolveName(n, (<Identifier>n).escapedText, SymbolFlags.Value | SymbolFlags.Alias, /*nameNotFoundMessage*/undefined, /*nameArg*/undefined, /*isUse*/ false);
@@ -25438,13 +25440,22 @@ namespace ts {
                                     if (current === node.initializer) {
                                         return "quit";
                                     }
-                                    return isFunctionLike(current.parent) ||
-                                        // computed property names/initializers in instance property declaration of class like entities
-                                        // are executed in constructor and thus deferred
-                                        (current.parent.kind === SyntaxKind.PropertyDeclaration &&
-                                         !(hasModifier(current.parent, ModifierFlags.Static)) &&
-                                         isClassLike(current.parent.parent));
-                                    })) {
+                                    if (current.kind === SyntaxKind.ComputedPropertyName) {
+                                        // computed property names are eagerly evaluated
+                                        return false;
+                                    }
+                                    if (isFunctionExpressionOrArrowFunction(current.parent)) {
+                                        // generator functions and async functions are not inlined in control flow when immediately invoked
+                                        if (current.parent.asteriskToken || hasModifier(current.parent, ModifierFlags.Async)) {
+                                            return true;
+                                        }
+                                        return !getImmediatelyInvokedFunctionExpression(current.parent);
+                                    }
+                                    return isFunctionLikeDeclaration(current.parent) ||
+                                        // initializers in instance property declaration of class like entities are executed in constructor and thus deferred
+                                        current.parent.kind === SyntaxKind.PropertyDeclaration && !hasModifier(current.parent, ModifierFlags.Static);
+                                })
+                            ) {
                                 return;
                             }
                             // fall through to report error

tests/baselines/reference/capturedParametersInInitializers1.errors.txt

@@ -0,0 +1,49 @@
+tests/cases/compiler/capturedParametersInInitializers1.ts(16,20): error TS2373: Initializer of parameter 'y' cannot reference identifier 'z' declared after it.
+tests/cases/compiler/capturedParametersInInitializers1.ts(20,26): error TS2373: Initializer of parameter 'y' cannot reference identifier 'z' declared after it.
+tests/cases/compiler/capturedParametersInInitializers1.ts(36,21): error TS2373: Initializer of parameter 'y' cannot reference identifier 'z' declared after it.
+
+
+==== tests/cases/compiler/capturedParametersInInitializers1.ts (3 errors) ====
+    // ok - usage is deferred
+    function foo1(y = class {c = x}, x = 1) {
+        new y().c;
+    }
+
+    // ok - used in function
+    function foo2(y = function z(x: typeof z) {}, z = 1) {
+    }
+
+    // ok -used in type
+    let a;
+    function foo3(y = { x: <typeof z>a }, z = 1) {
+    }
+
+    // error - used before declaration
+    function foo4(y = {z}, z = 1) {
+                       ~
+!!! error TS2373: Initializer of parameter 'y' cannot reference identifier 'z' declared after it.
+    }
+
+    // error - used before declaration, IIFEs are inlined
+    function foo5(y = (() => z)(), z = 1) {
+                             ~
+!!! error TS2373: Initializer of parameter 'y' cannot reference identifier 'z' declared after it.
+    }
+
+    // ok - IIFE inside another function
+    function foo6(y = () => (() => z)(), z = 1) {
+    }
+
+    // ok - used inside immediately invoked generator function
+    function foo7(y = (function*() {yield z})(), z = 1) {
+    }
+
+    // ok - used inside immediately invoked async function
+    function foo8(y = (async () => z)(), z = 1) {
+    }
+
+    // error - used as computed name of method
+    function foo9(y = {[z]() { return z; }}, z = 1) {
+                        ~
+!!! error TS2373: Initializer of parameter 'y' cannot reference identifier 'z' declared after it.
+    }

tests/baselines/reference/capturedParametersInInitializers1.js

@@ -4,37 +4,78 @@ function foo1(y = class {c = x}, x = 1) {
     new y().c;
 }
 
-// ok - used in file
-function foo2(y = function(x: typeof z) {}, z = 1) {
-
+// ok - used in function
+function foo2(y = function z(x: typeof z) {}, z = 1) {
 }
 
 // ok -used in type
 let a;
 function foo3(y = { x: <typeof z>a }, z = 1) {
-
+}
+
+// error - used before declaration
+function foo4(y = {z}, z = 1) {
+}
+
+// error - used before declaration, IIFEs are inlined
+function foo5(y = (() => z)(), z = 1) {
+}
+
+// ok - IIFE inside another function
+function foo6(y = () => (() => z)(), z = 1) {
+}
+
+// ok - used inside immediately invoked generator function
+function foo7(y = (function*() {yield z})(), z = 1) {
+}
+
+// ok - used inside immediately invoked async function
+function foo8(y = (async () => z)(), z = 1) {
+}
+
+// error - used as computed name of method
+function foo9(y = {[z]() { return z; }}, z = 1) {
 }
 
 //// [capturedParametersInInitializers1.js]
+var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
+    return new (P || (P = Promise))(function (resolve, reject) {
+        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
+        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
+        function step(result) { result.done ? resolve(result.value) : new P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); }
+        step((generator = generator.apply(thisArg, _arguments || [])).next());
+    });
+};
 // ok - usage is deferred
-function foo1(y, x) {
-    if (y === void 0) { y = /** @class */ (function () {
-        function class_1() {
-            this.c = x;
-        }
-        return class_1;
-    }()); }
-    if (x === void 0) { x = 1; }
+function foo1(y = class {
+    constructor() {
+        this.c = x;
+    }
+}, x = 1) {
     new y().c;
 }
-// ok - used in file
-function foo2(y, z) {
-    if (y === void 0) { y = function (x) { }; }
-    if (z === void 0) { z = 1; }
+// ok - used in function
+function foo2(y = function z(x) { }, z = 1) {
 }
 // ok -used in type
-var a;
-function foo3(y, z) {
-    if (y === void 0) { y = { x: a }; }
-    if (z === void 0) { z = 1; }
+let a;
+function foo3(y = { x: a }, z = 1) {
+}
+// error - used before declaration
+function foo4(y = { z }, z = 1) {
+}
+// error - used before declaration, IIFEs are inlined
+function foo5(y = (() => z)(), z = 1) {
+}
+// ok - IIFE inside another function
+function foo6(y = () => (() => z)(), z = 1) {
+}
+// ok - used inside immediately invoked generator function
+function foo7(y = (function* () { yield z; })(), z = 1) {
+}
+// ok - used inside immediately invoked async function
+function foo8(y = (() => __awaiter(this, void 0, void 0, function* () { return z; }))(), z = 1) {
+}
+// error - used as computed name of method
+function foo9(y = { [z]() { return z; } }, z = 1) {
 }

tests/baselines/reference/capturedParametersInInitializers1.symbols

@@ -13,26 +13,75 @@ function foo1(y = class {c = x}, x = 1) {
 >c : Symbol((Anonymous class).c, Decl(capturedParametersInInitializers1.ts, 1, 25))
 }
 
-// ok - used in file
-function foo2(y = function(x: typeof z) {}, z = 1) {
+// ok - used in function
+function foo2(y = function z(x: typeof z) {}, z = 1) {
 >foo2 : Symbol(foo2, Decl(capturedParametersInInitializers1.ts, 3, 1))
 >y : Symbol(y, Decl(capturedParametersInInitializers1.ts, 6, 14))
->x : Symbol(x, Decl(capturedParametersInInitializers1.ts, 6, 27))
->z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 6, 43))
->z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 6, 43))
-    
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 6, 17))
+>x : Symbol(x, Decl(capturedParametersInInitializers1.ts, 6, 29))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 6, 17))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 6, 45))
 }
 
 // ok -used in type
 let a;
->a : Symbol(a, Decl(capturedParametersInInitializers1.ts, 11, 3))
+>a : Symbol(a, Decl(capturedParametersInInitializers1.ts, 10, 3))
 
 function foo3(y = { x: <typeof z>a }, z = 1) {
->foo3 : Symbol(foo3, Decl(capturedParametersInInitializers1.ts, 11, 6))
->y : Symbol(y, Decl(capturedParametersInInitializers1.ts, 12, 14))
->x : Symbol(x, Decl(capturedParametersInInitializers1.ts, 12, 19))
->z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 12, 37))
->a : Symbol(a, Decl(capturedParametersInInitializers1.ts, 11, 3))
->z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 12, 37))
-
+>foo3 : Symbol(foo3, Decl(capturedParametersInInitializers1.ts, 10, 6))
+>y : Symbol(y, Decl(capturedParametersInInitializers1.ts, 11, 14))
+>x : Symbol(x, Decl(capturedParametersInInitializers1.ts, 11, 19))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 11, 37))
+>a : Symbol(a, Decl(capturedParametersInInitializers1.ts, 10, 3))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 11, 37))
+}
+
+// error - used before declaration
+function foo4(y = {z}, z = 1) {
+>foo4 : Symbol(foo4, Decl(capturedParametersInInitializers1.ts, 12, 1))
+>y : Symbol(y, Decl(capturedParametersInInitializers1.ts, 15, 14))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 15, 19))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 15, 22))
+}
+
+// error - used before declaration, IIFEs are inlined
+function foo5(y = (() => z)(), z = 1) {
+>foo5 : Symbol(foo5, Decl(capturedParametersInInitializers1.ts, 16, 1))
+>y : Symbol(y, Decl(capturedParametersInInitializers1.ts, 19, 14))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 19, 30))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 19, 30))
+}
+
+// ok - IIFE inside another function
+function foo6(y = () => (() => z)(), z = 1) {
+>foo6 : Symbol(foo6, Decl(capturedParametersInInitializers1.ts, 20, 1))
+>y : Symbol(y, Decl(capturedParametersInInitializers1.ts, 23, 14))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 23, 36))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 23, 36))
+}
+
+// ok - used inside immediately invoked generator function
+function foo7(y = (function*() {yield z})(), z = 1) {
+>foo7 : Symbol(foo7, Decl(capturedParametersInInitializers1.ts, 24, 1))
+>y : Symbol(y, Decl(capturedParametersInInitializers1.ts, 27, 14))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 27, 44))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 27, 44))
+}
+
+// ok - used inside immediately invoked async function
+function foo8(y = (async () => z)(), z = 1) {
+>foo8 : Symbol(foo8, Decl(capturedParametersInInitializers1.ts, 28, 1))
+>y : Symbol(y, Decl(capturedParametersInInitializers1.ts, 31, 14))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 31, 36))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 31, 36))
+}
+
+// error - used as computed name of method
+function foo9(y = {[z]() { return z; }}, z = 1) {
+>foo9 : Symbol(foo9, Decl(capturedParametersInInitializers1.ts, 32, 1))
+>y : Symbol(y, Decl(capturedParametersInInitializers1.ts, 35, 14))
+>[z] : Symbol([z], Decl(capturedParametersInInitializers1.ts, 35, 19))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 35, 40))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 35, 40))
+>z : Symbol(z, Decl(capturedParametersInInitializers1.ts, 35, 40))
 }

tests/baselines/reference/capturedParametersInInitializers1.types

@@ -16,16 +16,16 @@ function foo1(y = class {c = x}, x = 1) {
 >c : number
 }
 
-// ok - used in file
-function foo2(y = function(x: typeof z) {}, z = 1) {
->foo2 : (y?: (x: number) => void, z?: number) => void
->y : (x: number) => void
->function(x: typeof z) {} : (x: number) => void
->x : number
->z : number
+// ok - used in function
+function foo2(y = function z(x: typeof z) {}, z = 1) {
+>foo2 : (y?: (x: any) => void, z?: number) => void
+>y : (x: any) => void
+>function z(x: typeof z) {} : (x: any) => void
+>z : (x: any) => void
+>x : (x: any) => void
+>z : (x: any) => void
 >z : number
 >1 : 1
-
 }
 
 // ok -used in type
@@ -42,5 +42,76 @@ function foo3(y = { x: <typeof z>a }, z = 1) {
 >a : any
 >z : number
 >1 : 1
-
+}
+
+// error - used before declaration
+function foo4(y = {z}, z = 1) {
+>foo4 : (y?: { z: number; }, z?: number) => void
+>y : { z: number; }
+>{z} : { z: number; }
+>z : number
+>z : number
+>1 : 1
+}
+
+// error - used before declaration, IIFEs are inlined
+function foo5(y = (() => z)(), z = 1) {
+>foo5 : (y?: number, z?: number) => void
+>y : number
+>(() => z)() : number
+>(() => z) : () => number
+>() => z : () => number
+>z : number
+>z : number
+>1 : 1
+}
+
+// ok - IIFE inside another function
+function foo6(y = () => (() => z)(), z = 1) {
+>foo6 : (y?: () => number, z?: number) => void
+>y : () => number
+>() => (() => z)() : () => number
+>(() => z)() : number
+>(() => z) : () => number
+>() => z : () => number
+>z : number
+>z : number
+>1 : 1
+}
+
+// ok - used inside immediately invoked generator function
+function foo7(y = (function*() {yield z})(), z = 1) {
+>foo7 : (y?: IterableIterator<number>, z?: number) => void
+>y : IterableIterator<number>
+>(function*() {yield z})() : IterableIterator<number>
+>(function*() {yield z}) : () => IterableIterator<number>
+>function*() {yield z} : () => IterableIterator<number>
+>yield z : any
+>z : number
+>z : number
+>1 : 1
+}
+
+// ok - used inside immediately invoked async function
+function foo8(y = (async () => z)(), z = 1) {
+>foo8 : (y?: Promise<number>, z?: number) => void
+>y : Promise<number>
+>(async () => z)() : Promise<number>
+>(async () => z) : () => Promise<number>
+>async () => z : () => Promise<number>
+>z : number
+>z : number
+>1 : 1
+}
+
+// error - used as computed name of method
+function foo9(y = {[z]() { return z; }}, z = 1) {
+>foo9 : (y?: { [x: number]: () => number; }, z?: number) => void
+>y : { [x: number]: () => number; }
+>{[z]() { return z; }} : { [x: number]: () => number; }
+>[z] : () => number
+>z : number
+>z : number
+>z : number
+>1 : 1
 }