eval_cli: Initialize themes in eval headless mode (#57139)

Also fix patch generation

Release Notes:

- N/A

Cargo.lock

@@ -5964,6 +5964,8 @@ dependencies = [
  "settings",
  "shellexpand",
  "terminal_view",
+ "theme",
+ "theme_settings",
  "util",
  "watch",
 ]

crates/eval_cli/Cargo.toml

@@ -47,5 +47,7 @@ serde_json.workspace = true
 settings.workspace = true
 shellexpand.workspace = true
 terminal_view.workspace = true
+theme.workspace = true
+theme_settings.workspace = true
 util.workspace = true
 watch.workspace = true

crates/eval_cli/src/headless.rs

@@ -40,6 +40,7 @@ pub fn init(cx: &mut App) -> Arc<AgentCliAppState> {
 
     let settings_store = SettingsStore::new(cx, &settings::default_settings());
     cx.set_global(settings_store);
+    theme_settings::init(theme::LoadThemes::JustBase, cx);
 
     let user_agent = format!(
         "Zed Agent CLI/{} ({}; {})",

crates/eval_cli/zed_eval/agent.py

@@ -443,16 +443,21 @@ class ZedAgent(BaseInstalledAgent):
             env=env,
         )
 
-        # Only generate a patch if the workdir is a git repo
+        # Only generate a patch if the workdir is a git repo with a valid HEAD
-        # (SWE-bench style). Terminal-bench containers aren't git repos.
+        # (SWE-bench style). Terminal-bench containers aren't git repos, and
+        # some harnesses mount an initialized repo before creating the first commit.
         await self.exec_as_agent(
             environment,
             command=(
-                'if [ -d ".git" ]; then '
+                "if git rev-parse --git-dir >/dev/null 2>&1; then "
                 "git add -A && "
-                "git diff --cached HEAD > /logs/agent/patch.diff && "
+                "if git rev-parse --verify HEAD >/dev/null 2>&1; then "
+                "git diff --cached HEAD -- > /logs/agent/patch.diff && "
                 'echo "Patch size: $(wc -c < /logs/agent/patch.diff) bytes"; '
                 "else "
+                'echo "Git repo has no valid HEAD, skipping patch generation"; '
+                "fi; "
+                "else "
                 'echo "No git repo found, skipping patch generation"; '
                 "fi"
             ),