Enhance placeholder to show diffs from the merge base when comparing to the current branch

Author: robertpiosik

packages/vscode/package.json

@@ -1,8 +1,8 @@
 {
   "name": "gemini-coder",
   "displayName": "Code Web Chat (CWC)",
-  "description": "Initialize your favorite chatbot, then apply the response with a single click",
-  "version": "1.149.0",
+  "description": "Connect your editor with 10+ chatbots",
+  "version": "1.150.0",
   "scripts": {
     "build": "npx vsce package --no-dependencies",
     "vscode:prepublish": "npm run compile",

packages/vscode/src/utils/replace-changes-placeholder/replace-changes-placeholder.ts

@@ -35,7 +35,14 @@ export const replace_changes_placeholder = async (
     }
 
     try {
-      const diff = execSync(`git diff ${branch_name}`, {
+      // Get current branch name
+      const current_branch = execSync('git rev-parse --abbrev-ref HEAD', {
+        cwd: target_folder.uri.fsPath
+      }).toString().trim()
+
+      // If comparing to same branch, use merge-base to show changes since branch point
+      const diff_command = current_branch == branch_name ? `git diff $(git merge-base HEAD origin/${branch_name})` : `git diff ${branch_name}`
+      const diff = execSync(diff_command, {
         cwd: target_folder.uri.fsPath
       }).toString()
 
@@ -74,7 +81,14 @@ export const replace_changes_placeholder = async (
     }
 
     try {
-      const diff = execSync(`git diff ${branch_name}`, {
+      // Get current branch name
+      const current_branch = execSync('git rev-parse --abbrev-ref HEAD', {
+        cwd: repository.rootUri.fsPath
+      }).toString().trim()
+
+      // If comparing to same branch, use merge-base to show changes since branch point
+      const diff_command = current_branch == branch_name ? `git diff $(git merge-base HEAD origin/${branch_name})` : `git diff ${branch_name}`
+      const diff = execSync(diff_command, {
         cwd: repository.rootUri.fsPath
       }).toString()