fix: Remove top level support (currently not possible)

src/discoverer/evaluate.ts

@@ -30,8 +30,6 @@ import { IExtensionSettings, IParsedNode, ITestDiscoverer, NodeKind } from './ty
  */
 
 export class EvaluationTestDiscoverer implements ITestDiscoverer {
-  private static readonly asyncEntryStart = '(async function(){';
-  private static readonly asyncEntryEnd = '})()';
   constructor(
     private logChannel: vscode.LogOutputChannel | undefined,
     private symbols: IExtensionSettings,
@@ -122,14 +120,6 @@ export class EvaluationTestDiscoverer implements ITestDiscoverer {
         startLine--;
         endLine--;
 
-        // top level await wrapper begin
-        if (startLine === 0) {
-          startColumn -= EvaluationTestDiscoverer.asyncEntryStart.length;
-        }
-        if (endLine === 0) {
-          endColumn -= EvaluationTestDiscoverer.asyncEntryStart.length;
-        }
-
         if (endLine === startLine) {
           endColumn = Number.MAX_SAFE_INTEGER; // assume it takes the entire line of a single-line test case
         } else {
@@ -169,13 +159,11 @@ export class EvaluationTestDiscoverer implements ITestDiscoverer {
     }
 
     let sourceMap: TraceMap | undefined;
+    const needsTranspile = isTypeScript(filePath) || isEsm(filePath, code);
     // transpile typescript or ESM via esbuild if needed
-    if (isTypeScript(filePath) || isEsm(filePath, code)) {
+    if (needsTranspile) {
       const tsconfig = this.tsconfigStore.getTsconfig(filePath);
 
-      // NOTE: CJS does not support top level awaits, we add a wrapper for that.
-      code = `${EvaluationTestDiscoverer.asyncEntryStart}${code}${EvaluationTestDiscoverer.asyncEntryEnd}`;
-
       const result = await esbuildTransform(code, {
         target: `node${process.versions.node.split('.')[0]}`, // target current runtime
         sourcemap: true, // need source map for correct test positions

src/test/integration/typescript-top-level-await.test.ts

@@ -0,0 +1,18 @@
+/**
+ * Copyright (C) Daniel Kuschny (Danielku15) and contributors.
+ * Copyright (C) Microsoft Corporation. All rights reserved.
+ *
+ * Use of this source code is governed by an MIT-style
+ * license that can be found in the LICENSE file or at
+ * https://opensource.org/licenses/MIT.
+ */
+
+import { expectTestTree, getController } from '../util';
+
+describe('typescript top level await', () => {
+  it('discovers tests fails', async () => {
+    const c = await getController();
+
+    await expectTestTree(c, []);
+  });
+});

src/test/unit/extract/syntax.test.ts

@@ -20,8 +20,8 @@ describe('syntax', () => {
     return discoverer.discover('test.js', source(...lines));
   }
 
-  it('extracts basic suite', () => {
-    const src = extractWithAst(
+  it('extracts basic suite', async () => {
+    const src = await extractWithAst(
       "suite('hello', () => {", //
       "  it('works', () => {});",
       '})',
@@ -49,8 +49,8 @@ describe('syntax', () => {
     ]);
   });
 
-  it('works with skip/only', () => {
-    const src = extractWithAst(
+  it('works with skip/only', async () => {
+    const src = await extractWithAst(
       "suite('hello', () => {", //
       "  it.only('a', ()=>{});",
       "  it.skip('a', ()=>{});",
@@ -90,8 +90,8 @@ describe('syntax', () => {
     ]);
   });
 
-  it('can detect suite but not dynamic tests', () => {
-    const src = extractWithAst(
+  it('can detect suite but not dynamic tests', async () => {
+    const src = await extractWithAst(
       "suite('hello', () => {", //
       "  for (const name of ['foo', 'bar', 'baz']) {",
       '    it(name, () => {});',
@@ -111,8 +111,8 @@ describe('syntax', () => {
     ]);
   });
 
-  it('stubs out requires and placeholds correctly', () => {
-    const src = extractWithAst('require("some invalid module").doing().other.things()');
+  it('stubs out requires and placeholds correctly', async () => {
+    const src = await extractWithAst('require("some invalid module").doing().other.things()');
     expect(src).to.deep.equal([]);
   });
 });

test-workspaces/typescript-top-level-await/.mocharc.js

@@ -0,0 +1,11 @@
+module.exports = {
+    spec: '**/*.test.ts',
+    extension: [
+        "ts"
+    ],
+    "node-option": [
+        "experimental-specifier-resolution=node",
+        "import=tsx",
+        "no-warnings"
+    ],
+};

test-workspaces/typescript-top-level-await/hello.test.ts

@@ -0,0 +1,26 @@
+import { strictEqual } from 'node:assert';
+
+// just some typescript code which would be valid directly in Node
+
+function topLevel(a: number): string {
+  return a.toString() as string;
+}
+
+const fn = async () => {};
+await fn();
+
+describe('math', () => {
+  function inDescribe(a: number): string {
+    return a.toString() as string;
+  }
+  inDescribe(1);
+  topLevel(0);
+
+  it('addition', async () => {
+    strictEqual((1 + 1) as number, 2 as any as number);
+  });
+
+  it('subtraction', async () => {
+    strictEqual((1 - 1) as number, 0 as any as number);
+  });
+});

test-workspaces/typescript/hello.test.ts

@@ -6,9 +6,6 @@ function topLevel(a: number): string {
   return a.toString() as string;
 }
 
-const fn = async () => {};
-await fn();
-
 describe('math', () => {
   function inDescribe(a: number): string {
     return a.toString() as string;