nixos/test-driver: add polling_condition

nixos/lib/test-driver/test_driver/machine.py

@@ -17,6 +17,7 @@ import threading
 import time
 
 from test_driver.logger import rootlog
+from test_driver.polling_condition import PollingCondition, coopmulti
 
 CHAR_TO_KEY = {
     "A": "shift-a",
@@ -318,6 +319,7 @@ class Machine:
     # Store last serial console lines for use
     # of wait_for_console_text
     last_lines: Queue = Queue()
+    fail_early: Callable
 
     def __repr__(self) -> str:
         return f"<Machine '{self.name}'>"
@@ -329,12 +331,14 @@ class Machine:
         name: str = "machine",
         keep_vm_state: bool = False,
         allow_reboot: bool = False,
+        fail_early: Callable = lambda: False,
     ) -> None:
         self.tmp_dir = tmp_dir
         self.keep_vm_state = keep_vm_state
         self.allow_reboot = allow_reboot
         self.name = name
         self.start_command = start_command
+        self.fail_early = fail_early
 
         # set up directories
         self.shared_dir = self.tmp_dir / "shared-xchg"
@@ -405,6 +409,7 @@ class Machine:
                     break
             return answer
 
+    @coopmulti
     def send_monitor_command(self, command: str) -> str:
         with self.nested("sending monitor command: {}".format(command)):
             message = ("{}\n".format(command)).encode()
@@ -506,6 +511,7 @@ class Machine:
                 break
         return "".join(output_buffer)
 
+    @coopmulti
     def execute(
         self, command: str, check_return: bool = True, timeout: Optional[int] = 900
     ) -> Tuple[int, str]: