Merge pull request 'hotfix(cli): replace raw subprocess tracebacks with styled error messages and fix restart race condition' (#96) from hotfix-restart-race-condition into main

Reviewed-on: #96
Reviewed-by: zach <zach@brohn.se>

cli/src/zshell/subcommands/shell.py

@@ -1,4 +1,8 @@
 import subprocess
+import sys
+import time
+
+import click
 import typer
 
 args = ["qs", "-c", "zshell"]
@@ -8,35 +12,68 @@ app = typer.Typer()
 
 @app.command()
 def kill():
-    subprocess.run(args + ["kill"], check=True)
+    result = subprocess.run(args + ["kill"], capture_output=True)
+    if result.returncode != 0:
+        raise click.ClickException("No running instance to kill.")
+    sys.stderr.write(result.stderr.decode())
+
+
+def start_instance(no_daemon: bool = False) -> None:
+    result = subprocess.run(args + ["-n"] + ([] if no_daemon else ["-d"]), capture_output=True)
+    stdout = result.stdout.decode().strip()
+    if stdout:
+        if "already running" in stdout.lower():
+            raise click.ClickException(stdout)
+    if result.returncode != 0:
+        stderr = result.stderr.decode().strip()
+        raise click.ClickException(stderr)
 
 
 @app.command()
 def start(no_daemon: bool = False):
-    subprocess.run(args + ["-n"] + ([] if no_daemon else ["-d"]), check=True)
+    start_instance(no_daemon)
 
 
 @app.command()
 def restart(no_daemon: bool = False):
-    subprocess.run(args + ["kill"], check=False)
+    subprocess.run(args + ["kill"], capture_output=True)
-    subprocess.run(args + ["-n"] + ([] if no_daemon else ["-d"]), check=True)
+    deadline = time.monotonic() + 2.5
+    while time.monotonic() < deadline:
+        result = subprocess.run(args + ["kill"], capture_output=True)
+        if result.returncode == 255:
+            break
+        time.sleep(0.25)
+    start_instance(no_daemon=no_daemon)
 
 
 @app.command()
 def show():
-    subprocess.run(args + ["ipc"] + ["show"], check=True)
+    result = subprocess.run(args + ["ipc"] + ["show"], capture_output=True)
+    if result.returncode != 0:
+        raise click.ClickException(result.stderr.decode().strip())
+    sys.stderr.write(result.stderr.decode())
 
 
 @app.command()
 def log():
-    subprocess.run(args + ["log"], check=True)
+    result = subprocess.run(args + ["log"], capture_output=True)
+    if result.returncode != 0:
+        raise click.ClickException(result.stderr.decode().strip())
+    sys.stdout.write(result.stdout.decode())
+    sys.stderr.write(result.stderr.decode())
 
 
 @app.command()
 def lock():
-    subprocess.run(args + ["ipc"] + ["call"] + ["lock"] + ["lock"], check=True)
+    result = subprocess.run(args + ["ipc"] + ["call"] + ["lock"] + ["lock"], capture_output=True)
+    if result.returncode != 0:
+        raise click.ClickException(result.stderr.decode().strip())
+    sys.stderr.write(result.stderr.decode())
 
 
 @app.command()
 def call(target: str, method: str, method_args: list[str] = typer.Argument(None)):
-    subprocess.run(args + ["ipc"] + ["call"] + [target] + [method] + (method_args or []), check=True)
+    result = subprocess.run(args + ["ipc"] + ["call"] + [target] + [method] + (method_args or []), capture_output=True)
+    if result.returncode != 0:
+        raise click.ClickException(result.stderr.decode().strip())
+    sys.stderr.write(result.stderr.decode())

cli/tests/test_shell.py

@@ -1,13 +1,15 @@
 from __future__ import annotations
 
+from subprocess import CompletedProcess
 from unittest.mock import patch, call
+
+from typer.testing import CliRunner
 from zshell.subcommands.shell import app
 
+runner = CliRunner()
 
-def invoke(*args: str) -> None:
-    from typer.testing import CliRunner
 
-    runner = CliRunner()
+def invoke(*args: str):
     result = runner.invoke(app, args)
     if result.exit_code != 0:
         raise RuntimeError(result.output)
@@ -16,72 +18,113 @@ def invoke(*args: str) -> None:
 
 class TestKill:
     @patch("zshell.subcommands.shell.subprocess.run")
-    def test_kill_runs_qs_kill(self, mock_run):
+    def test_kill_runs_qs_kill_success(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 0, b"", b"Killed abc\n")
         invoke("kill")
-        mock_run.assert_called_once_with(["qs", "-c", "zshell", "kill"], check=True)
+        mock_run.assert_called_once_with(["qs", "-c", "zshell", "kill"], capture_output=True)
+
+    @patch("zshell.subcommands.shell.subprocess.run")
+    def test_kill_no_instance_errors(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 255, b"", b"No running instances\n")
+        result = runner.invoke(app, ["kill"])
+        assert result.exit_code != 0
+        assert "No running instance to kill" in result.output
 
 
 class TestStart:
     @patch("zshell.subcommands.shell.subprocess.run")
     def test_start_default_daemon(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 0, b"", b"Launching config\n")
         invoke("start")
-        mock_run.assert_called_once_with(["qs", "-c", "zshell", "-n", "-d"], check=True)
+        mock_run.assert_called_once_with(["qs", "-c", "zshell", "-n", "-d"], capture_output=True)
 
     @patch("zshell.subcommands.shell.subprocess.run")
     def test_start_no_daemon(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 0, b"", b"Launching config\n")
         invoke("start", "--no-daemon")
-        mock_run.assert_called_once_with(["qs", "-c", "zshell", "-n"], check=True)
+        mock_run.assert_called_once_with(["qs", "-c", "zshell", "-n"], capture_output=True)
+
+    @patch("zshell.subcommands.shell.subprocess.run")
+    def test_start_already_running_errors(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 0, b"An instance of this configuration is already running.\n", b"")
+        result = runner.invoke(app, ["start"])
+        assert result.exit_code != 0
+        assert "already running" in result.output
+
+    @patch("zshell.subcommands.shell.subprocess.run")
+    def test_start_other_failure_errors(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 1, b"", b"Config error\n")
+        result = runner.invoke(app, ["start"])
+        assert result.exit_code != 0
+        assert "Config error" in result.output
 
 
 class TestShow:
     @patch("zshell.subcommands.shell.subprocess.run")
     def test_show_runs_ipc_show(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 0, b"", b"target visibilities\n")
         invoke("show")
-        mock_run.assert_called_once_with(["qs", "-c", "zshell", "ipc", "show"], check=True)
+        mock_run.assert_called_once_with(["qs", "-c", "zshell", "ipc", "show"], capture_output=True)
 
 
 class TestLog:
     @patch("zshell.subcommands.shell.subprocess.run")
     def test_log_runs_qs_log(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 0, b"log output\n", b"")
         invoke("log")
-        mock_run.assert_called_once_with(["qs", "-c", "zshell", "log"], check=True)
+        mock_run.assert_called_once_with(["qs", "-c", "zshell", "log"], capture_output=True)
 
 
 class TestLock:
     @patch("zshell.subcommands.shell.subprocess.run")
     def test_lock_runs_ipc_call_lock(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 0, b"", b"")
         invoke("lock")
-        mock_run.assert_called_once_with(["qs", "-c", "zshell", "ipc", "call", "lock", "lock"], check=True)
+        mock_run.assert_called_once_with(["qs", "-c", "zshell", "ipc", "call", "lock", "lock"], capture_output=True)
 
 
 class TestCall:
     @patch("zshell.subcommands.shell.subprocess.run")
     def test_call_no_args(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 0, b"", b"")
         invoke("call", "target", "method")
-        mock_run.assert_called_once_with(["qs", "-c", "zshell", "ipc", "call", "target", "method"], check=True)
+        mock_run.assert_called_once_with(["qs", "-c", "zshell", "ipc", "call", "target", "method"], capture_output=True)
 
     @patch("zshell.subcommands.shell.subprocess.run")
     def test_call_with_args(self, mock_run):
+        mock_run.return_value = CompletedProcess([], 0, b"", b"")
         invoke("call", "target", "method", "arg1", "arg2")
         mock_run.assert_called_once_with(
             ["qs", "-c", "zshell", "ipc", "call", "target", "method", "arg1", "arg2"],
-            check=True,
+            capture_output=True,
         )
 
 
 class TestRestart:
+    @patch("zshell.subcommands.shell.start_instance")
     @patch("zshell.subcommands.shell.subprocess.run")
-    def test_restart_kills_then_starts_daemon(self, mock_run):
+    def test_restart_kills_then_starts(self, mock_run, mock_start):
+        mock_run.side_effect = [
+            CompletedProcess([], 0, b"", b"Killed abc\n"),  # first kill (captured)
+            CompletedProcess([], 255, b"", b""),  # poll → no instance
+        ]
         invoke("restart")
         assert mock_run.call_args_list == [
-            call(["qs", "-c", "zshell", "kill"], check=False),
+            call(["qs", "-c", "zshell", "kill"], capture_output=True),
-            call(["qs", "-c", "zshell", "-n", "-d"], check=True),
+            call(["qs", "-c", "zshell", "kill"], capture_output=True),
         ]
+        mock_start.assert_called_once_with(no_daemon=False)
 
+    @patch("zshell.subcommands.shell.start_instance")
     @patch("zshell.subcommands.shell.subprocess.run")
-    def test_restart_no_daemon(self, mock_run):
+    def test_restart_no_daemon(self, mock_run, mock_start):
+        mock_run.side_effect = [
+            CompletedProcess([], 0, b"", b"Killed abc\n"),
+            CompletedProcess([], 255, b"", b""),
+        ]
         invoke("restart", "--no-daemon")
         assert mock_run.call_args_list == [
-            call(["qs", "-c", "zshell", "kill"], check=False),
+            call(["qs", "-c", "zshell", "kill"], capture_output=True),
-            call(["qs", "-c", "zshell", "-n"], check=True),
+            call(["qs", "-c", "zshell", "kill"], capture_output=True),
         ]
+        mock_start.assert_called_once_with(no_daemon=True)