Revert "[interactive] Ignore SIGWINCH in the shell."

This reverts commit 3ab4e69.

Author: Andy C

core/comp_ui.py

@@ -518,11 +518,6 @@ def _GetTerminalWidth(self):
 
   def OnWindowChange(self):
     # type: () -> None
-    """
-    Note: SIGWINCH handler in core/pyos.py no longer calls this.
-    The shell process should probably handle SIGWINCH only when blocked in
-    readline().
-    """
     # Only do it for the NEXT completion.  The signal handler can be run in
     # between arbitrary bytecodes, and we don't want a single completion
     # display to be shown with different widths.

core/pyos.py

@@ -282,10 +282,7 @@ def InitInteractiveShell(self, display):
 
     # Register a callback to receive terminal width changes.
     # NOTE: In line_input.c, we turned off rl_catch_sigwinch.
-    #signal.signal(signal.SIGWINCH, lambda x, y: display.OnWindowChange())
-
-    # Disabled because it causes wait builtin to abort (issue 1067)
-    signal.signal(signal.SIGWINCH, signal.SIG_IGN)
+    signal.signal(signal.SIGWINCH, lambda x, y: display.OnWindowChange())
 
   def AddUserTrap(self, sig_num, handler):
     # type: (int, Any) -> None

test/interactive.py

@@ -42,22 +42,22 @@ def get_pid_by_name(name):
   # XXX: make sure this is restricted to subprocesses under us.
   # This could be problematic on the continuous build if many tests are running
   # in parallel.
-  output = pexpect.run('pgrep --exact --newest %s' % name)
+  output = pexpect.run('pgrep --exact --newest cat')
   return int(output.split()[-1])
 
 
-def send_signal(name, sig_num):
-  """Kill the most recent process matching `name`."""
-  os.kill(get_pid_by_name(name), sig_num)
-
-
 # XXX: osh.sendcontrol("z") does not suspend the foreground process :(
 #
 # why does osh.sendcontrol("c") generate SIGINT, while osh.sendcontrol("z")
 # appears to do nothing?
 def stop_process__hack(name):
   """Send sigstop to the most recent process matching `name`"""
-  send_signal(name, signal.SIGSTOP)
+  os.kill(get_pid_by_name(name), signal.SIGSTOP)
+
+
+def kill_process(name):
+  """Kill the most recent process matching `name`."""
+  os.kill(get_pid_by_name(name), signal.SIGINT)
 
 
 class InteractiveTest(object):
@@ -119,22 +119,6 @@ def __exit__(self, t, v, tb):
 
 
 def main(argv):
-  with InteractiveTest('wait builtin then SIGWINCH (issue 1067)') as osh:
-    osh.sendline('sleep 1 &')
-    osh.sendline('wait')
-
-    time.sleep(0.1)
-
-    # simulate window size change
-    osh.kill(signal.SIGWINCH)
-
-    osh.expect(r'.*\$')  # expect prompt
-
-    osh.sendline('echo status=$?')
-    osh.expect('status=0')
-
-  #return
-
   with InteractiveTest('Ctrl-C during external command') as osh:
     osh.sendline('sleep 5')
 
@@ -217,7 +201,7 @@ def main(argv):
     osh.expect(r".*\$")
     osh.sendline("fg")
     osh.expect(r"Continue PID \d+")
-    send_signal("cat", signal.SIGINT)
+    kill_process("cat")
     osh.expect(r".*\$")
     osh.sendline("fg")
     osh.expect("No job to put in the foreground")