chore: add pre-commit fmt hook

4 files changed, 37 insertions, 3 deletions

diff --git a/.githooks/pre-commit b/.githooks/pre-commit
new file mode 100755
index 00000000..249d41f7
--- /dev/null
+++ b/.githooks/pre-commit
@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+repo_root="$(git rev-parse --show-toplevel)"
+cd "$repo_root"
+
+echo "pre-commit: running cargo fmt --check"
+cargo fmt --check
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 5a4784d5..42a08593 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -48,6 +48,14 @@ If you plan to implement the change yourself, say that directly in the issue and
 
 ## Before submitting a PR
 
+Install the repo hook once in your clone.
+
+```bash
+just install-hooks
+```
+
+The pre-commit hook runs `cargo fmt --check` before every commit.
+
 Run the PR checks and make sure they pass.
 
 ```bash
diff --git a/justfile b/justfile
index 4dd729c4..3232568b 100644
--- a/justfile
+++ b/justfile
@@ -14,6 +14,12 @@ ci:
 check: ci
     python3 -m unittest scripts.test_changelog scripts.test_vendor_libghostty_vt
 
+# Install repo-local git hooks
+install-hooks:
+    git config core.hooksPath .githooks
+    chmod +x .githooks/pre-commit
+    @echo "installed git hooks from .githooks"
+
 # Build release binary
 build:
     cargo build --release
diff --git a/tests/cli_wrapper.rs b/tests/cli_wrapper.rs
index 9da11061..8c8574d3 100644
--- a/tests/cli_wrapper.rs
+++ b/tests/cli_wrapper.rs
@@ -396,8 +396,17 @@ fn pane_close_only_removes_the_target_tab_when_other_tabs_exist() {
     let workspaces = run_cli(&socket_path, &["workspace", "list"]);
     assert!(workspaces.status.success());
     let workspaces_json: serde_json::Value = serde_json::from_slice(&workspaces.stdout).unwrap();
-    assert_eq!(workspaces_json["result"]["workspaces"].as_array().unwrap().len(), 1);
-    assert_eq!(workspaces_json["result"]["workspaces"][0]["workspace_id"], workspace_id);
+    assert_eq!(
+        workspaces_json["result"]["workspaces"]
+            .as_array()
+            .unwrap()
+            .len(),
+        1
+    );
+    assert_eq!(
+        workspaces_json["result"]["workspaces"][0]["workspace_id"],
+        workspace_id
+    );
 
     let tabs = run_cli(&socket_path, &["tab", "list", "--workspace", &workspace_id]);
     assert!(tabs.status.success());
@@ -436,7 +445,10 @@ fn pane_close_removes_the_workspace_when_it_closes_the_last_pane() {
     let workspaces = run_cli(&socket_path, &["workspace", "list"]);
     assert!(workspaces.status.success());
     let workspaces_json: serde_json::Value = serde_json::from_slice(&workspaces.stdout).unwrap();
-    assert!(workspaces_json["result"]["workspaces"].as_array().unwrap().is_empty());
+    assert!(workspaces_json["result"]["workspaces"]
+        .as_array()
+        .unwrap()
+        .is_empty());
 
     cleanup_spawned_herdr(herdr, base);
 }