From e0eeec7af483ef3703eb7c287c4e34b4fe1553ae Mon Sep 17 00:00:00 2001
From: Krish Garg <kgarg@chapman.edu>
Date: Thu, 21 May 2026 19:04:24 -0700
Subject: [PATCH] fix(filesystem): preserve literal dollar replacements

---
 src/filesystem/__tests__/lib.test.ts | 16 ++++++++++++++++
 src/filesystem/lib.ts                |  2 +-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/filesystem/__tests__/lib.test.ts b/src/filesystem/__tests__/lib.test.ts
index f7e585af22..e0ae61224f 100644
--- a/src/filesystem/__tests__/lib.test.ts
+++ b/src/filesystem/__tests__/lib.test.ts
@@ -440,6 +440,22 @@ describe('Lib Functions', () => {
         );
       });
 
+      it('treats dollar signs in replacement text literally', async () => {
+        const edits = [
+          { oldText: 'line2', newText: "price=$$; match=$&; before=$`; after=$'" }
+        ];
+
+        mockFs.rename.mockResolvedValueOnce(undefined);
+
+        await applyFileEdits('/test/file.txt', edits, false);
+
+        expect(mockFs.writeFile).toHaveBeenCalledWith(
+          expect.stringMatching(/\/test\/file\.txt\.[a-f0-9]+\.tmp$/),
+          "line1\nprice=$$; match=$&; before=$`; after=$'\nline3\n",
+          'utf-8'
+        );
+      });
+
       it('handles dry run mode', async () => {
         const edits = [
           { oldText: 'line2', newText: 'modified line2' }
diff --git a/src/filesystem/lib.ts b/src/filesystem/lib.ts
index 17e4654cd5..ce4af9f38a 100644
--- a/src/filesystem/lib.ts
+++ b/src/filesystem/lib.ts
@@ -207,7 +207,7 @@ export async function applyFileEdits(
 
     // If exact match exists, use it
     if (modifiedContent.includes(normalizedOld)) {
-      modifiedContent = modifiedContent.replace(normalizedOld, normalizedNew);
+      modifiedContent = modifiedContent.replace(normalizedOld, () => normalizedNew);
       continue;
     }