Fix isolatedModules check for export assignments (#57148)

Author: andrewbranch

src/compiler/checker.ts

@@ -46384,11 +46384,12 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                     );
                 }
 
-                if (!isIllegalExportDefaultInCJS && getIsolatedModules(compilerOptions) && !(sym.flags & SymbolFlags.Value)) {
+                if (!isIllegalExportDefaultInCJS && !(node.flags & NodeFlags.Ambient) && getIsolatedModules(compilerOptions) && !(sym.flags & SymbolFlags.Value)) {
+                    const nonLocalMeanings = getSymbolFlags(sym, /*excludeTypeOnlyMeanings*/ false, /*excludeLocalMeanings*/ true);
                     if (
                         sym.flags & SymbolFlags.Alias
-                        && resolveAlias(sym) !== unknownSymbol
-                        && getSymbolFlags(sym, /*excludeTypeOnlyMeanings*/ false, /*excludeLocalMeanings*/ true) & SymbolFlags.Type
+                        && nonLocalMeanings & SymbolFlags.Type
+                        && !(nonLocalMeanings & SymbolFlags.Value)
                         && (!typeOnlyDeclaration || getSourceFileOfNode(typeOnlyDeclaration) !== getSourceFileOfNode(node))
                     ) {
                         // import { SomeType } from "./someModule";

tests/baselines/reference/exportDeclaration(isolatedmodules=true).errors.txt

@@ -1,5 +1,5 @@
 /b.ts(3,5): error TS1362: 'A' cannot be used as a value because it was exported using 'export type'.
-/d.ts(2,10): error TS1291: 'A' resolves to a type and must be marked type-only in this file before re-exporting when 'isolatedModules' is enabled. Consider using 'import type' where 'A' is imported.
+/d.ts(2,10): error TS1289: 'A' resolves to a type-only declaration and must be marked type-only in this file before re-exporting when 'isolatedModules' is enabled. Consider using 'import type' where 'A' is imported.
 
 
 ==== /a.ts (0 errors) ====
@@ -22,4 +22,5 @@
     import { A } from './a';
     export = A;
              ~
-!!! error TS1291: 'A' resolves to a type and must be marked type-only in this file before re-exporting when 'isolatedModules' is enabled. Consider using 'import type' where 'A' is imported.
+!!! error TS1289: 'A' resolves to a type-only declaration and must be marked type-only in this file before re-exporting when 'isolatedModules' is enabled. Consider using 'import type' where 'A' is imported.
+!!! related TS1377 /a.ts:2:15: 'A' was exported here.

tests/cases/compiler/isolatedModulesReExportAlias.ts

@@ -0,0 +1,25 @@
+// @isolatedModules: true
+// @noEmit: true
+// @noTypesAndSymbols: true
+
+// @Filename: /events.d.ts
+declare module "events" {
+  interface EventEmitterOptions {
+    captureRejections?: boolean;
+  }
+  class EventEmitter {
+    constructor(options?: EventEmitterOptions);
+  }
+  export = EventEmitter;
+}
+declare module "node:events" {
+  import events = require("events");
+  export = events;
+}
+
+// @Filename: /moreEvents.ts
+import events = require("events");
+export = events;
+
+// @Filename: /boo.ts
+// Bad test runner (ignores stuff when last file contains the string r-e-q-u-i-r-e)