fix(integrations): Replace possibly expensive regex with string.includes

Author: srubin

packages/integrations/src/rewriteframes.ts

@@ -72,8 +72,9 @@ export class RewriteFrames implements Integration {
       return frame;
     }
     // Determine if this is a Windows frame by checking for a Windows-style prefix such as `C:\`
-    // or the presence of a backslash without a forward slash (which are not allowed on Windows)
-    const isWindowsFrame = /^[a-zA-Z]:\\/.test(frame.filename) || /^(?!.*\/).*\\.*$/.test(frame.filename);
+    const isWindowsFrame = /^[a-zA-Z]:\\/.test(frame.filename) ||
+      // or the presence of a backslash without a forward slash (which are not allowed on Windows)
+      (frame.filename.includes('\\') && !frame.filename.includes('/'));
     // Check if the frame filename begins with `/`
     const startsWithSlash = /^\//.test(frame.filename);
     if (isWindowsFrame || startsWithSlash) {