fix: Raise error when aexpect_helper doesn't work properly

When aexpect_helper does not work properly, the process will hang
without any log information. This fix adds a timeout and checks the
process status and raises an error if the process terminates
prematurely.

Signed-off-by: Yihuang Yu <[email protected]>

aexpect/client.py

@@ -193,9 +193,19 @@ def __init__(self, command=None, a_id=None, auto_close=False, echo=False,
             sub.stdin.write(f"{command}\n".encode(self.encoding))
             sub.stdin.flush()
             # Wait for the server to complete its initialization
-            while (f"Server {self.a_id} ready" not in
-                   sub.stdout.readline().decode(self.encoding, "ignore")):
-                pass
+            full_output = ""
+            pattern = f"Server {self.a_id} ready"
+            end_time = time.time() + 60
+            while time.time() < end_time:
+                output = sub.stdout.readline().decode(self.encoding, "ignore")
+                if pattern in output:
+                    break
+                full_output += output
+                sub_status = sub.poll()
+                if sub_status is not None:
+                    raise ExpectProcessTerminatedError(pattern, sub_status, full_output)
+            else:
+                raise ExpectTimeoutError(pattern, full_output)
 
         # Open the reading pipes
         if is_file_locked(self.lock_server_running_filename):