Skip and reset loop checking around code blocks (#5144)

packages/core/src/services/loopDetectionService.ts

@@ -61,6 +61,7 @@ export class LoopDetectionService {
   private contentStats = new Map<string, number[]>();
   private lastContentIndex = 0;
   private loopDetected = false;
+  private inCodeBlock = false;
 
   // LLM loop track tracking
   private turnsInCurrentPrompt = 0;
@@ -156,8 +157,27 @@ export class LoopDetectionService {
    * 2. Truncating history if it exceeds the maximum length
    * 3. Analyzing content chunks for repetitive patterns using hashing
    * 4. Detecting loops when identical chunks appear frequently within a short distance
+   * 5. Disabling loop detection within code blocks to prevent false positives,
+   *    as repetitive code structures are common and not necessarily loops.
    */
   private checkContentLoop(content: string): boolean {
+    // Code blocks can often contain repetitive syntax that is not indicative of a loop.
+    // To avoid false positives, we detect when we are inside a code block and
+    // temporarily disable loop detection.
+    const numFences = (content.match(/```/g) ?? []).length;
+    if (numFences) {
+      // Reset tracking when a code fence is detected to avoid analyzing content
+      // that spans across code block boundaries.
+      this.resetContentTracking();
+    }
+
+    const wasInCodeBlock = this.inCodeBlock;
+    this.inCodeBlock =
+      numFences % 2 === 0 ? this.inCodeBlock : !this.inCodeBlock;
+    if (wasInCodeBlock) {
+      return false;
+    }
+
     this.streamContentHistory += content;
 
     this.truncateAndUpdate();