Ran black code formatter on everything.
[python_utils.git] / exec_utils.py
index a52e206ad95496ebf4de9eb08f19df8073339d4a..016310793152ddeb8872f5ec279c26ae1994655e 100644 (file)
@@ -12,7 +12,9 @@ from typing import List, Optional
 logger = logging.getLogger(__file__)
 
 
-def cmd_showing_output(command: str, ) -> int:
+def cmd_showing_output(
+    command: str,
+) -> int:
     """Kick off a child process.  Capture and print all output that it
     produces on stdout and stderr.  Wait for the subprocess to exit
     and return the exit value as the return code of this function.
@@ -30,12 +32,13 @@ def cmd_showing_output(command: str, ) -> int:
     sel = selectors.DefaultSelector()
     sel.register(p.stdout, selectors.EVENT_READ)
     sel.register(p.stderr, selectors.EVENT_READ)
-    should_exit = False
-    while not should_exit:
+    stream_ends = 0
+    while stream_ends < 2:
         for key, _ in sel.select():
             char = key.fileobj.read(1)
             if not char:
-                should_exit = True
+                stream_ends += 1
+                continue
             if key.fileobj is p.stdout:
                 sys.stdout.buffer.write(char)
                 if char in line_enders:
@@ -45,6 +48,8 @@ def cmd_showing_output(command: str, ) -> int:
                 if char in line_enders:
                     sys.stderr.flush()
     p.wait()
+    sys.stdout.flush()
+    sys.stderr.flush()
     return p.returncode
 
 
@@ -116,25 +121,30 @@ def run_silently(command: str, timeout_seconds: Optional[float] = None) -> None:
 
 
 def cmd_in_background(
-        command: str, *, silent: bool = False
+    command: str, *, silent: bool = False
 ) -> subprocess.Popen:
     args = shlex.split(command)
     if silent:
-        subproc = subprocess.Popen(args,
-                                   stdin=subprocess.DEVNULL,
-                                   stdout=subprocess.DEVNULL,
-                                   stderr=subprocess.DEVNULL)
+        subproc = subprocess.Popen(
+            args,
+            stdin=subprocess.DEVNULL,
+            stdout=subprocess.DEVNULL,
+            stderr=subprocess.DEVNULL,
+        )
     else:
         subproc = subprocess.Popen(args, stdin=subprocess.DEVNULL)
 
     def kill_subproc() -> None:
         try:
             if subproc.poll() is None:
-                logger.info("At exit handler: killing {}: {}".format(subproc, command))
+                logger.info(
+                    "At exit handler: killing {}: {}".format(subproc, command)
+                )
                 subproc.terminate()
                 subproc.wait(timeout=10.0)
         except BaseException as be:
             logger.exception(be)
+
     atexit.register(kill_subproc)
     return subproc
 
@@ -149,4 +159,5 @@ def cmd_list(command: List[str]) -> str:
 
 if __name__ == '__main__':
     import doctest
+
     doctest.testmod()