From 412aa3c035c331b7209a2adae4ec2987584e536e Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Fri, 18 Jul 2025 00:11:07 +0200
Subject: [PATCH] Fix server crash when Claude status contains regex special
 characters (#398)

---
 web/src/server/utils/activity-detector.ts    | 49 +++++++++++++-------
 web/src/test/utils/activity-detector.test.ts | 31 +++++++++++++
 2 files changed, 63 insertions(+), 17 deletions(-)

diff --git a/web/src/server/utils/activity-detector.ts b/web/src/server/utils/activity-detector.ts
index 26d38de3..ee52dabe 100644
--- a/web/src/server/utils/activity-detector.ts
+++ b/web/src/server/utils/activity-detector.ts
@@ -24,6 +24,13 @@ function superDebug(message: string, ...args: unknown[]): void {
 // biome-ignore lint/suspicious/noControlCharactersInRegex: ANSI escape codes need control characters
 const ANSI_REGEX = /\x1b\[[0-9;]*[a-zA-Z]/g;
 
+/**
+ * Escape special regex characters in a string
+ */
+function escapeRegex(str: string): string {
+  return str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+}
+
 /**
  * Activity status returned by app-specific parsers
  */
@@ -169,7 +176,10 @@ function parseClaudeStatus(data: string): ActivityStatus | null {
       originalPos + fullMatch.length + 50
     );
     // Look for the status pattern in the middle section
-    const statusPattern = new RegExp(`[^\n]*${indicator}[^\n]*to\\s+interrupt[^\n]*`, 'gi');
+    const statusPattern = new RegExp(
+      `[^\n]*${escapeRegex(indicator)}[^\n]*to\\s+interrupt[^\n]*`,
+      'gi'
+    );
     const cleanedMiddle = middle.replace(statusPattern, '');
     filteredData = before + cleanedMiddle + after;
   }
@@ -271,23 +281,28 @@ export class ActivityDetector {
 
     // Try app-specific detection first
     if (this.detector) {
-      const status = this.detector.parseStatus(data);
-      if (status) {
-        this.currentStatus = status;
-        this.lastStatusTime = Date.now();
-        // Always update activity time for app-specific status
-        this.lastActivityTime = Date.now();
-        return {
-          filteredData: status.filteredData,
-          activity: {
-            isActive: true,
-            lastActivityTime: this.lastActivityTime,
-            specificStatus: {
-              app: this.detector.name,
-              status: status.displayText,
+      try {
+        const status = this.detector.parseStatus(data);
+        if (status) {
+          this.currentStatus = status;
+          this.lastStatusTime = Date.now();
+          // Always update activity time for app-specific status
+          this.lastActivityTime = Date.now();
+          return {
+            filteredData: status.filteredData,
+            activity: {
+              isActive: true,
+              lastActivityTime: this.lastActivityTime,
+              specificStatus: {
+                app: this.detector.name,
+                status: status.displayText,
+              },
             },
-          },
-        };
+          };
+        }
+      } catch (error) {
+        logger.error(`Error in ${this.detector.name} status parser:`, error);
+        // Continue with unfiltered data if parsing fails
       }
     }
 
diff --git a/web/src/test/utils/activity-detector.test.ts b/web/src/test/utils/activity-detector.test.ts
index b38bc00f..084cc89f 100644
--- a/web/src/test/utils/activity-detector.test.ts
+++ b/web/src/test/utils/activity-detector.test.ts
@@ -130,6 +130,37 @@ describe('Activity Detector', () => {
       expect(result.filteredData).toBe(claudeOutput);
       expect(result.activity.specificStatus).toBeUndefined();
     });
+
+    it('should handle regex special characters in status indicators', () => {
+      const detector = new ActivityDetector(['claude']);
+
+      // Test with * which is a regex special character that was causing crashes
+      const statusWithStar = '* Processing… (42s · ↑ 1.2k tokens · esc to interrupt)\n';
+      const result1 = detector.processOutput(statusWithStar);
+      expect(result1.activity.specificStatus?.status).toBe('Processing (42s, ↑1.2k)');
+      expect(result1.filteredData).toBe('\n');
+
+      // Test with other regex special characters
+      const specialChars = ['*', '+', '?', '.', '^', '$', '|', '(', ')', '[', ']', '{', '}', '\\'];
+      for (const char of specialChars) {
+        const statusWithSpecialChar = `${char} Testing… (10s · ↑ 1.0k tokens · esc to interrupt)\n`;
+        const result = detector.processOutput(statusWithSpecialChar);
+        expect(result.activity.specificStatus?.status).toBe('Testing (10s, ↑1.0k)');
+        expect(result.filteredData).toBe('\n');
+      }
+    });
+
+    it('should not crash when parsing fails', () => {
+      const detector = new ActivityDetector(['claude']);
+
+      // Even if something unexpected happens, it should not crash
+      const malformedOutput = 'Some output that might cause issues\n';
+      expect(() => {
+        const result = detector.processOutput(malformedOutput);
+        expect(result.filteredData).toBe(malformedOutput);
+        expect(result.activity.specificStatus).toBeUndefined();
+      }).not.toThrow();
+    });
   });
 
   describe('registerDetector', () => {