Fix __setFunctionName overriding custom static name property

src/compiler/factory/emitHelpers.ts

@@ -1024,6 +1024,8 @@ const setFunctionNameHelper: UnscopedEmitHelper = {
     text: `
         var __setFunctionName = (this && this.__setFunctionName) || function (f, name, prefix) {
             if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+            var d = Object.getOwnPropertyDescriptor(f, "name");
+            if (d && d.writable !== false) return f;
             return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
         };`,
 };

tests/baselines/reference/blockScopedVariablesUseBeforeDef.js

@@ -200,6 +200,8 @@ var __generator = (this && this.__generator) || function (thisArg, body) {
 };
 var __setFunctionName = (this && this.__setFunctionName) || function (f, name, prefix) {
     if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+    var d = Object.getOwnPropertyDescriptor(f, "name");
+    if (d && d.writable !== false) return f;
     return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
 };
 var __await = (this && this.__await) || function (v) { return this instanceof __await ? (this.v = v, this) : new __await(v); }

tests/baselines/reference/capturedParametersInInitializers2.js

@@ -19,6 +19,8 @@ function foo2(y = class {[x] = x}, x = 1) {
 //// [capturedParametersInInitializers2.js]
 var __setFunctionName = (this && this.__setFunctionName) || function (f, name, prefix) {
     if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+    var d = Object.getOwnPropertyDescriptor(f, "name");
+    if (d && d.writable !== false) return f;
     return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
 };
 function foo(y, x, z) {

tests/baselines/reference/classStaticBlock18(target=es2015).js

@@ -19,6 +19,8 @@ function foo () {
 //// [classStaticBlock18.js]
 var __setFunctionName = (this && this.__setFunctionName) || function (f, name, prefix) {
     if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+    var d = Object.getOwnPropertyDescriptor(f, "name");
+    if (d && d.writable !== false) return f;
     return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
 };
 function foo() {

tests/baselines/reference/classStaticBlock18(target=es5).js

@@ -19,6 +19,8 @@ function foo () {
 //// [classStaticBlock18.js]
 var __setFunctionName = (this && this.__setFunctionName) || function (f, name, prefix) {
     if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+    var d = Object.getOwnPropertyDescriptor(f, "name");
+    if (d && d.writable !== false) return f;
     return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
 };
 function foo() {

tests/baselines/reference/classWithStaticFieldInParameterInitializer(target=es2015).js

@@ -7,6 +7,8 @@
 //// [classWithStaticFieldInParameterInitializer.js]
 var __setFunctionName = (this && this.__setFunctionName) || function (f, name, prefix) {
     if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+    var d = Object.getOwnPropertyDescriptor(f, "name");
+    if (d && d.writable !== false) return f;
     return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
 };
 // https://github.com/microsoft/TypeScript/issues/36295

tests/baselines/reference/classWithStaticFieldInParameterInitializer(target=es5).js

@@ -7,6 +7,8 @@
 //// [classWithStaticFieldInParameterInitializer.js]
 var __setFunctionName = (this && this.__setFunctionName) || function (f, name, prefix) {
     if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+    var d = Object.getOwnPropertyDescriptor(f, "name");
+    if (d && d.writable !== false) return f;
     return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
 };
 // https://github.com/microsoft/TypeScript/issues/36295

tests/baselines/reference/decoratorOnClass8.es6.js

@@ -17,6 +17,8 @@ var __decorate = (this && this.__decorate) || function (decorators, target, key,
 };
 var __setFunctionName = (this && this.__setFunctionName) || function (f, name, prefix) {
     if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+    var d = Object.getOwnPropertyDescriptor(f, "name");
+    if (d && d.writable !== false) return f;
     return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
 };
 var _a;

tests/baselines/reference/emitClassExpressionInDeclarationFile2.js

@@ -50,6 +50,8 @@ var __extends = (this && this.__extends) || (function () {
 })();
 var __setFunctionName = (this && this.__setFunctionName) || function (f, name, prefix) {
     if (typeof name === "symbol") name = name.description ? "[".concat(name.description, "]") : "";
+    var d = Object.getOwnPropertyDescriptor(f, "name");
+    if (d && d.writable !== false) return f;
     return Object.defineProperty(f, "name", { configurable: true, value: prefix ? "".concat(prefix, " ", name) : name });
 };
 var _a;