Fix auto context to exclude file paths inside liquid comment tags

Related to #59

Exclude file paths inside liquid comment tags from being sent to the LLM.

* Update `src/services/AutoContext.js` to filter out file paths inside liquid comment tags when extracting file paths from the prompt.
* Add a helper function `isInsideLiquidComment` to check if a file path is inside a liquid comment tag.
* Add test cases in `test/AutoContext.test.js` to verify that file paths inside liquid comment tags are excluded.

---

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src/services/AutoContext.js

@@ -11,11 +11,26 @@ export default class AutoContext {
     let match;
 
     while ((match = regex.exec(prompt)) !== null) {
-      if (!filePaths.includes(match[1])) {
+      if (!filePaths.includes(match[1]) && !this.isInsideLiquidComment(prompt, match.index)) {
         filePaths.push(match[1]);
       }
     }
 
     return filePaths;
   }
-}
+
+  /**
+   * Checks if a file path is inside a liquid comment tag.
+   *
+   * @param {string} prompt - The input prompt containing file paths.
+   * @param {number} index - The index of the file path in the prompt.
+   * @returns {boolean} True if the file path is inside a liquid comment tag, false otherwise.
+   */
+  static isInsideLiquidComment(prompt, index) {
+    const before = prompt.slice(0, index);
+    const after = prompt.slice(index);
+    const openTag = before.lastIndexOf('{% comment %}');
+    const closeTag = before.lastIndexOf('{% endcomment %}');
+    return openTag > closeTag && after.includes('{% endcomment %}');
+  }
+}

test/AutoContext.test.js

@@ -51,6 +51,21 @@ describe('AutoContext.call', () => {
       assert.deepStrictEqual([
         '/src/services/AutoContext.js'
     ], result)
+  })
+
+  describe('when the prompt mentions paths inside liquid comment tags', () => {
+    let prompt = `
+      Instructions here
+
+      {% comment %}
+      // this file shouldn't be included in the prompt sent to the LLM
+      See file /abc/test.txt
+      {% endcomment %}
+    `
+
+    it('excludes paths inside liquid comment tags', () => {
+      const result = AutoContext.call(prompt)
+      assert.deepStrictEqual([], result)
     })
   })
 })