🤖 Show unpushed commit details in SSH workspace deletion errors (#479)

## Problem

When SSH workspace deletion is blocked due to unpushed commits, users
only see:
```
Workspace contains unpushed commits. Use force flag to delete anyway.
```

This lacks critical context about what commits would be lost, making it
hard to decide whether to force delete.

## Solution

Enhanced the unpushed commits error to include the actual commit list
(up to 10 commits) in standard git log format.

**Implementation approach:**
- Capture `git log --branches --not --remotes --oneline` output to
stderr in the deletion check
- Include stderr directly in error message (no parsing - simpler and
more robust)
- Update ForceDeleteModal warning text to be more specific when unpushed
commits detected
- Add test verifying commit details appear in error

## UX Impact

**Before:**
```
Git Error
Workspace contains unpushed commits. Use force flag to delete anyway.
```

**After:**
```
Git Error  
Workspace contains unpushed commits:

a1b2c3d Fix critical bug in validation
d4e5f6g Add user authentication
h7i8j9k Update documentation

⚠️ This action cannot be undone
Force deleting will permanently remove the workspace and discard
the unpushed commits shown above. This action cannot be undone.
```

Users can now see exactly which commits they're about to lose, making
informed decisions about force deletion.

## Testing

- ✅ New test verifies commit list appears in error message
- ✅ All 15 deletion tests pass (7 local + 5 SSH + 3 SSH-only)
- ✅ Typecheck passes
- ✅ Formatting correct

_Generated with `cmux`_

---------

Co-authored-by: Ammar Bandukwala <ammar@ammar.io>

Author: ammar-agent

src/components/ForceDeleteModal.tsx

@@ -60,8 +60,11 @@ export const ForceDeleteModal: React.FC<ForceDeleteModalProps> = ({
       <WarningBox>
         <WarningTitle>This action cannot be undone</WarningTitle>
         <WarningText>
-          Force deleting will permanently remove the workspace and may discard uncommitted work or
-          lose data.
+          Force deleting will permanently remove the workspace and{" "}
+          {error.includes("unpushed commits:")
+            ? "discard the unpushed commits shown above"
+            : "may discard uncommitted work or lose data"}
+          . This action cannot be undone.
         </WarningText>
       </WarningBox>
 

src/runtime/SSHRuntime.ts

@@ -984,7 +984,11 @@ export class SSHRuntime implements Runtime {
             cd ${shescape.quote(deletedPath)} || exit 1
             git diff --quiet --exit-code && git diff --quiet --cached --exit-code || exit 1
             if git remote | grep -q .; then
-              git log --branches --not --remotes --oneline | head -1 | grep -q . && exit 2
+              unpushed=$(git log --branches --not --remotes --oneline)
+              if [ -n "$unpushed" ]; then
+                echo "$unpushed" | head -10 >&2
+                exit 2
+              fi
             fi
             exit 0
           `;
@@ -1012,9 +1016,28 @@ export class SSHRuntime implements Runtime {
       }
 
       if (checkExitCode === 2) {
+        // Read stderr which contains the unpushed commits output
+        const stderrReader = checkStream.stderr.getReader();
+        const decoder = new TextDecoder();
+        let stderr = "";
+        try {
+          while (true) {
+            const { done, value } = await stderrReader.read();
+            if (done) break;
+            stderr += decoder.decode(value, { stream: true });
+          }
+        } finally {
+          stderrReader.releaseLock();
+        }
+
+        const commitList = stderr.trim();
+        const errorMsg = commitList
+          ? `Workspace contains unpushed commits:\n\n${commitList}`
+          : `Workspace contains unpushed commits. Use force flag to delete anyway.`;
+
         return {
           success: false,
-          error: `Workspace contains unpushed commits. Use force flag to delete anyway.`,
+          error: errorMsg,
         };
       }
 

tests/ipcMain/removeWorkspace.test.ts

@@ -614,5 +614,67 @@ describeIntegration("Workspace deletion integration tests", () => {
       },
       TEST_TIMEOUT_SSH_MS
     );
+
+    test.concurrent(
+      "should include commit list in error for unpushed refs",
+      async () => {
+        const env = await createTestEnvironment();
+        const tempGitRepo = await createTempGitRepo();
+
+        try {
+          const branchName = generateBranchName("delete-unpushed-details");
+          const runtimeConfig = getRuntimeConfig(branchName);
+          const { workspaceId } = await createWorkspaceWithInit(
+            env,
+            tempGitRepo,
+            branchName,
+            runtimeConfig,
+            true, // waitForInit
+            true // isSSH
+          );
+
+          // Configure git for committing (SSH environment needs this)
+          await executeBash(env, workspaceId, 'git config user.email "test@example.com"');
+          await executeBash(env, workspaceId, 'git config user.name "Test User"');
+
+          // Add a fake remote (needed for unpushed check to work)
+          await executeBash(
+            env,
+            workspaceId,
+            "git remote add origin https://github.com/fake/repo.git"
+          );
+
+          // Create multiple commits with descriptive messages
+          await executeBash(env, workspaceId, 'echo "1" > file1.txt');
+          await executeBash(env, workspaceId, "git add file1.txt");
+          await executeBash(env, workspaceId, 'git commit -m "First commit"');
+
+          await executeBash(env, workspaceId, 'echo "2" > file2.txt');
+          await executeBash(env, workspaceId, "git add file2.txt");
+          await executeBash(env, workspaceId, 'git commit -m "Second commit"');
+
+          // Attempt to delete
+          const deleteResult = await env.mockIpcRenderer.invoke(
+            IPC_CHANNELS.WORKSPACE_REMOVE,
+            workspaceId
+          );
+
+          // Should fail with error containing commit details
+          expect(deleteResult.success).toBe(false);
+          expect(deleteResult.error).toContain("unpushed commits:");
+          expect(deleteResult.error).toContain("First commit");
+          expect(deleteResult.error).toContain("Second commit");
+
+          // Cleanup: force delete for cleanup
+          await env.mockIpcRenderer.invoke(IPC_CHANNELS.WORKSPACE_REMOVE, workspaceId, {
+            force: true,
+          });
+        } finally {
+          await cleanupTestEnvironment(env);
+          await cleanupTempGitRepo(tempGitRepo);
+        }
+      },
+      TEST_TIMEOUT_SSH_MS
+    );
   });
 });