Merge pull request #376 from gescheit/master

dont remove reference to _UnixReadPipeTransport

2 files changed, 16 insertions, 6 deletions

diff --git a/pexpect/async.py b/pexpect/async.py
index 136fc0e..3a1a1ad 100644
--- a/pexpect/async.py
+++ b/pexpect/async.py
@@ -12,22 +12,30 @@ def expect_async(expecter, timeout=None):
     idx = expecter.new_data(previously_read)
     if idx is not None:
         return idx
-
-    transport, pw = yield from asyncio.get_event_loop()\
-        .connect_read_pipe(lambda: PatternWaiter(expecter), expecter.spawn)
-
+    if not expecter.spawn.async_pw_transport:
+        pw = PatternWaiter()
+        pw.set_expecter(expecter)
+        transport, pw = yield from asyncio.get_event_loop()\
+            .connect_read_pipe(lambda: pw, expecter.spawn)
+        expecter.spawn.async_pw_transport = pw, transport
+    else:
+        pw, transport = expecter.spawn.async_pw_transport
+        pw.set_expecter(expecter)
+        transport.resume_reading()
     try:
         return (yield from asyncio.wait_for(pw.fut, timeout))
     except asyncio.TimeoutError as e:
         transport.pause_reading()
         return expecter.timeout(e)
 
+
 class PatternWaiter(asyncio.Protocol):
     transport = None
-    def __init__(self, expecter):
+
+    def set_expecter(self, expecter):
         self.expecter = expecter
         self.fut = asyncio.Future()
-    
+
     def found(self, result):
         if not self.fut.done():
             self.fut.set_result(result)
diff --git a/pexpect/spawnbase.py b/pexpect/spawnbase.py
index 5dd24b5..cb64582 100644
--- a/pexpect/spawnbase.py
+++ b/pexpect/spawnbase.py
@@ -115,6 +115,8 @@ class SpawnBase(object):
                 self.linesep = os.linesep.decode('ascii')
             # This can handle unicode in both Python 2 and 3
             self.write_to_stdout = sys.stdout.write
+        # storage for async transport
+        self.async_pw_transport = None
 
     def _log(self, s, direction):
         if self.logfile is not None: