fix: When UNKNOWN errors are encountered, track the filenames and ski…

…p them when watching
getappmap · Dec 16, 2022 · d020e6e · d020e6e
1 parent c9eaf83
commit d020e6e
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Showing 2 changed files with 44 additions and 6 deletions.
diff --git a/packages/cli/src/fingerprint/fingerprintWatchCommand.ts b/packages/cli/src/fingerprint/fingerprintWatchCommand.ts
@@ -10,13 +10,15 @@ import { verbose } from '../utils';
 import { FingerprintEvent } from './fingerprinter';
 import FingerprintQueue from './fingerprintQueue';
 import Globber from './globber';
+import path from 'path';
 
 export default class FingerprintWatchCommand {
   private pidfilePath: string | undefined;
   public fpQueue: FingerprintQueue;
   public watcher?: FSWatcher;
   private poller?: Globber;
   private _numProcessed = 0;
+  public unreadableFiles = new Set();
 
   public get numProcessed() {
     return this._numProcessed;
@@ -45,6 +47,15 @@ export default class FingerprintWatchCommand {
     }
   }
 
+  getFilenameFromErrorMessage(errorMessage: string): string {
+    // The errorMessage must contain the filename within single quotes
+    // and looks like this:
+    // Error: UNKNOWN: unknown error, lstat 'c:\Users\Test\Programming\MyProject'
+    let quoteStartIndex = errorMessage.indexOf(`'`);
+    let quoteEndIndex = errorMessage.indexOf(`'`, quoteStartIndex + 1);
+    return errorMessage.substring(quoteStartIndex + 1, quoteEndIndex);
+  }
+
   async watcherErrorFunction (error: Error) {
     if (this.watcher && error.message.includes("ENOSPC: System limit for number of file watchers reached")) {
       console.warn(error.stack);
@@ -67,7 +78,10 @@ export default class FingerprintWatchCommand {
             errorMessage: error.message,
             errorStack: error.stack,
           },
-        });
+      });
+      const filename = this.getFilenameFromErrorMessage(error.message);
+      this.unreadableFiles.add(filename);
+      console.warn("Will not read this file again.");
     } else {
       // let it crash if it's some other error, to learn what the error is
       throw error;
@@ -90,9 +104,25 @@ export default class FingerprintWatchCommand {
     this.poller.start();
     await pollReady;
 
+    // Custom ignore function needed to skip unreadableFiles because
+    // attempting to read them can block reading all files. It also
+    // cuts down the watch tree to just what we need.
+    const ignored = (targetPath: string) => {
+      ['/node_modules/', '/.git/'].forEach((pattern) => {
+        if (this.unreadableFiles.has(targetPath) || targetPath.includes(pattern)) {
+          return true;
+        }
+      });
+
+      // Also make sure to not try to recurse down node_modules or .git
+      const basename = path.basename(targetPath);
+      return basename === 'node_modules' || basename === '.git';
+    };
+
+
     this.watcher = watch(glob, {
       ignoreInitial: true,
-      ignored: ['**/node_modules/**', '**/.git/**'],
+      ignored: ignored,
       ignorePermissionErrors: true,
     })
       .on('add', this.added.bind(this))

diff --git a/packages/cli/tests/unit/fingerprint/fingerprintWatchCommand.spec.ts b/packages/cli/tests/unit/fingerprint/fingerprintWatchCommand.spec.ts
@@ -91,18 +91,26 @@ describe(FingerprintWatchCommand, () => {
       expect(cmd.watcher).not.toBeUndefined();
       await cmd.watcherErrorFunction(new Error("ENOSPC: System limit for number of file watchers reached"));
       expect(cmd.watcher).toBeUndefined();
-     });
+    });
+
+    it('gets filenames from error messages', async () => {
+      cmd = new FingerprintWatchCommand(appMapDir);
+      expect(cmd.getFilenameFromErrorMessage(`Error: UNKNOWN: unknown error, lstat 'c:\\Users\\Test\\Programming\\MyProject'`)).toBe('c:\\Users\\Test\\Programming\\MyProject');
+    });
 
-     it('does not raise on unknown error lstat', async () => {
+    it('does not raise on unknown error lstat', async () => {
       cmd = new FingerprintWatchCommand(appMapDir);
       cmd.watcher = new FSWatcher();
       expect(cmd.watcher).not.toBeUndefined();
+      expect(cmd.unreadableFiles.size).toBe(0);
       console.warn = jest.fn();
-      const errorMessage = "UNKNOWN: unknown error, lstat";
+      const errorMessage = `Error: UNKNOWN: unknown error, lstat 'c:\\Users\\Test\\Programming\\MyProject'`;
       await cmd.watcherErrorFunction(new Error(errorMessage));
       expect(cmd.watcher).not.toBeUndefined();
-      expect(console.warn).toBeCalledTimes(1);
+      expect(console.warn).toBeCalledTimes(2);
       expect(console.warn).toHaveBeenCalledWith(expect.stringContaining(errorMessage));
+      expect(cmd.unreadableFiles.size).toBe(1);
+      expect(cmd.unreadableFiles.has('c:\\Users\\Test\\Programming\\MyProject')).toBe(true);
     });
 
     describe('telemetry', () => {