fix(typescript-eslint): handle file:// urls in stack trace when inferring tsconfigRootDir (#11464)

Author: kirkwaiblinger

.cspell.json

@@ -46,6 +46,7 @@
     "\\(#.+?\\)"
   ],
   "words": [
+    "AFAICT",
     "Airbnb",
     "Airbnb's",
     "allowdefaultproject",

packages/typescript-eslint/src/getTSConfigRootDirFromStack.ts

@@ -1,4 +1,5 @@
 import path from 'node:path';
+import { fileURLToPath } from 'node:url';
 
 /**
  * Infers the `tsconfigRootDir` from the current call stack, using the V8 API.
@@ -26,11 +27,18 @@ export function getTSConfigRootDirFromStack(): string | undefined {
   }
 
   for (const callSite of getStack()) {
-    const stackFrameFilePath = callSite.getFileName();
-    if (!stackFrameFilePath) {
+    const stackFrameFilePathOrUrl = callSite.getFileName();
+    if (!stackFrameFilePathOrUrl) {
       continue;
     }
 
+    // ESM seem to return a file URL, so we'll convert it to a file path.
+    // AFAICT this isn't documented in the v8 API docs, but it seems to be the case.
+    // See https://github.com/typescript-eslint/typescript-eslint/issues/11429
+    const stackFrameFilePath = stackFrameFilePathOrUrl.startsWith('file://')
+      ? fileURLToPath(stackFrameFilePathOrUrl)
+      : stackFrameFilePathOrUrl;
+
     const parsedPath = path.parse(stackFrameFilePath);
     if (/^eslint\.config\.(c|m)?(j|t)s$/.test(parsedPath.base)) {
       return parsedPath.dir;

packages/typescript-eslint/tests/getTsconfigRootDirFromStack.test.ts

@@ -3,11 +3,34 @@ import * as normalFolder from './path-test-fixtures/tsconfigRootDirInference-nor
 import * as notEslintConfig from './path-test-fixtures/tsconfigRootDirInference-not-eslint-config/not-an-eslint.config.cjs';
 import * as folderThatHasASpace from './path-test-fixtures/tsconfigRootDirInference-space/folder that has a space/eslint.config.cjs';
 
+const isWindows = process.platform === 'win32';
+
 describe(getTSConfigRootDirFromStack, () => {
   it('does stack analysis right for normal folder', () => {
     expect(normalFolder.get()).toBe(normalFolder.dirname());
   });
 
+  it('does stack analysis right for a file that gives a file:// URL as its name', () => {
+    vi.spyOn(Error, 'captureStackTrace').mockImplementationOnce(
+      // eslint-disable-next-line @typescript-eslint/no-explicit-any
+      (target: any, _constructorOpt) => {
+        target.stack = [
+          {
+            getFileName() {
+              return !isWindows
+                ? 'file:///a/b/eslint.config.mts'
+                : 'file:///F:/a/b/eslint.config.mts';
+            },
+          },
+        ];
+      },
+    );
+
+    const inferredTsconfigRootDir = getTSConfigRootDirFromStack();
+
+    expect(inferredTsconfigRootDir).toBe(!isWindows ? '/a/b' : 'F:\\a\\b');
+  });
+
   it('does stack analysis right for folder that has a space', () => {
     expect(folderThatHasASpace.get()).toBe(folderThatHasASpace.dirname());
   });