Merge pull request #29102 from Microsoft/declarationEmitForDefaultExportClassExtendingExpression

Declaration emit for default exported class extending expression

src/compiler/transformers/declarations.ts

@@ -1100,7 +1100,8 @@ namespace ts {
                     if (extendsClause && !isEntityNameExpression(extendsClause.expression) && extendsClause.expression.kind !== SyntaxKind.NullKeyword) {
                         // We must add a temporary declaration for the extends clause expression
 
-                        const newId = createOptimisticUniqueName(`${unescapeLeadingUnderscores(input.name!.escapedText)}_base`); // TODO: GH#18217
+                        const oldId = input.name ? unescapeLeadingUnderscores(input.name.escapedText) : "default";
+                        const newId = createOptimisticUniqueName(`${oldId}_base`);
                         getSymbolAccessibilityDiagnostic = () => ({
                             diagnosticMessage: Diagnostics.extends_clause_of_exported_class_0_has_or_is_using_private_name_1,
                             errorNode: extendsClause,

tests/baselines/reference/declarationEmitForDefaultExportClassExtendingExpression01.js

@@ -0,0 +1,68 @@
+//// [declarationEmitForDefaultExportClassExtendingExpression01.ts]
+interface Greeter {
+    getGreeting(): string;
+}
+
+interface GreeterConstructor {
+    new (): Greeter;
+}
+
+class A {
+    getGreeting() {
+        return 'hello';
+    }
+}
+
+const getGreeterBase = (): GreeterConstructor => A;
+
+export default class extends getGreeterBase() {
+}
+
+
+
+//// [declarationEmitForDefaultExportClassExtendingExpression01.js]
+"use strict";
+var __extends = (this && this.__extends) || (function () {
+    var extendStatics = function (d, b) {
+        extendStatics = Object.setPrototypeOf ||
+            ({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
+            function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
+        return extendStatics(d, b);
+    };
+    return function (d, b) {
+        extendStatics(d, b);
+        function __() { this.constructor = d; }
+        d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
+    };
+})();
+exports.__esModule = true;
+var A = /** @class */ (function () {
+    function A() {
+    }
+    A.prototype.getGreeting = function () {
+        return 'hello';
+    };
+    return A;
+}());
+var getGreeterBase = function () { return A; };
+var default_1 = /** @class */ (function (_super) {
+    __extends(default_1, _super);
+    function default_1() {
+        return _super !== null && _super.apply(this, arguments) || this;
+    }
+    return default_1;
+}(getGreeterBase()));
+exports["default"] = default_1;
+
+
+//// [declarationEmitForDefaultExportClassExtendingExpression01.d.ts]
+interface Greeter {
+    getGreeting(): string;
+}
+interface GreeterConstructor {
+    new (): Greeter;
+}
+declare const default_base: GreeterConstructor;
+export default class extends default_base {
+}
+export {};

tests/baselines/reference/declarationEmitForDefaultExportClassExtendingExpression01.symbols

@@ -0,0 +1,35 @@
+=== tests/cases/compiler/declarationEmitForDefaultExportClassExtendingExpression01.ts ===
+interface Greeter {
+>Greeter : Symbol(Greeter, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 0, 0))
+
+    getGreeting(): string;
+>getGreeting : Symbol(Greeter.getGreeting, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 0, 19))
+}
+
+interface GreeterConstructor {
+>GreeterConstructor : Symbol(GreeterConstructor, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 2, 1))
+
+    new (): Greeter;
+>Greeter : Symbol(Greeter, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 0, 0))
+}
+
+class A {
+>A : Symbol(A, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 6, 1))
+
+    getGreeting() {
+>getGreeting : Symbol(A.getGreeting, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 8, 9))
+
+        return 'hello';
+    }
+}
+
+const getGreeterBase = (): GreeterConstructor => A;
+>getGreeterBase : Symbol(getGreeterBase, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 14, 5))
+>GreeterConstructor : Symbol(GreeterConstructor, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 2, 1))
+>A : Symbol(A, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 6, 1))
+
+export default class extends getGreeterBase() {
+>getGreeterBase : Symbol(getGreeterBase, Decl(declarationEmitForDefaultExportClassExtendingExpression01.ts, 14, 5))
+}
+
+

tests/baselines/reference/declarationEmitForDefaultExportClassExtendingExpression01.types

@@ -0,0 +1,32 @@
+=== tests/cases/compiler/declarationEmitForDefaultExportClassExtendingExpression01.ts ===
+interface Greeter {
+    getGreeting(): string;
+>getGreeting : () => string
+}
+
+interface GreeterConstructor {
+    new (): Greeter;
+}
+
+class A {
+>A : A
+
+    getGreeting() {
+>getGreeting : () => string
+
+        return 'hello';
+>'hello' : "hello"
+    }
+}
+
+const getGreeterBase = (): GreeterConstructor => A;
+>getGreeterBase : () => GreeterConstructor
+>(): GreeterConstructor => A : () => GreeterConstructor
+>A : typeof A
+
+export default class extends getGreeterBase() {
+>getGreeterBase() : Greeter
+>getGreeterBase : () => GreeterConstructor
+}
+
+

tests/cases/compiler/declarationEmitForDefaultExportClassExtendingExpression01.ts

@@ -0,0 +1,21 @@
+// @declaration: true
+
+interface Greeter {
+    getGreeting(): string;
+}
+
+interface GreeterConstructor {
+    new (): Greeter;
+}
+
+class A {
+    getGreeting() {
+        return 'hello';
+    }
+}
+
+const getGreeterBase = (): GreeterConstructor => A;
+
+export default class extends getGreeterBase() {
+}
+