PR #66: TypeError thrown by spawnu.readline()

Submitted by @auntieNeo, fixes exception, "TypeError:
got <type 'str'> ('\r\n') as pattern" in spawnu.readline().

Bytes b'\r\n' was concatenated to u'unicode', causing an
exception to be thrown when using readline().

4 files changed, 24 insertions, 2 deletions

diff --git a/doc/history.rst b/doc/history.rst
index 81ad48b..245b24c 100644
--- a/doc/history.rst
+++ b/doc/history.rst
@@ -14,6 +14,8 @@ Version 3.3
 * Removed the ``pexpect.psh`` module. This was never documented, and we found
   no evidence that people use it. The new :mod:`pexpect.replwrap` module
   provides a more flexible alternative.
+* Fixed ``TypeError: got <type 'str'> ('\r\n') as pattern`` in ``readline()``
+  method of ``spawnu`` (:ghissue:`67`).
 
 Version 3.2
 ```````````
diff --git a/pexpect/__init__.py b/pexpect/__init__.py
index f27e3fe..dab85c0 100644
--- a/pexpect/__init__.py
+++ b/pexpect/__init__.py
@@ -284,6 +284,7 @@ class spawn(object):
         def _chr(c):
             return bytes([c])
         linesep = os.linesep.encode('ascii')
+        crlf = '\r\n'.encode('ascii')
 
         @staticmethod
         def write_to_stdout(b):
@@ -296,6 +297,7 @@ class spawn(object):
         allowed_string_types = (basestring,)  # analysis:ignore
         _chr = staticmethod(chr)
         linesep = os.linesep
+        crlf = '\r\n'
         write_to_stdout = sys.stdout.write
 
     encoding = None
@@ -970,9 +972,9 @@ class spawn(object):
         if size == 0:
             return self.string_type()
         # delimiter default is EOF
-        index = self.expect([b'\r\n', self.delimiter])
+        index = self.expect([self.crlf, self.delimiter])
         if index == 0:
-            return self.before + b'\r\n'
+            return self.before + self.crlf
         else:
             return self.before
 
@@ -1730,11 +1732,13 @@ class spawnu(spawn):
         allowed_string_types = (str, )
         _chr = staticmethod(chr)
         linesep = os.linesep
+        crlf = '\r\n'
     else:
         string_type = unicode
         allowed_string_types = (unicode, )
         _chr = staticmethod(unichr)
         linesep = os.linesep.decode('ascii')
+        crlf = '\r\n'.decode('ascii')
     # This can handle unicode in both Python 2 and 3
     write_to_stdout = sys.stdout.write
 
diff --git a/tests/test_misc.py b/tests/test_misc.py
index 7569070..93ff930 100755
--- a/tests/test_misc.py
+++ b/tests/test_misc.py
@@ -49,6 +49,13 @@ class TestCaseMisc(PexpectTestCase.PexpectTestCase):
         remaining = child.read().replace(_CAT_EOF, b'')
         self.assertEqual(remaining, b'abc\r\n')
 
+    def test_readline_bin_echo(self):
+        # given,
+        child = pexpect.spawn('echo', ['input', ])
+
+        # exercise,
+        assert child.readline() == b'input' + child.crlf
+
     def test_readline (self):
         '''See the note in test_readlines() for an explaination as to why
         I allow line3 and line4 to return multiple patterns.
diff --git a/tests/test_unicode.py b/tests/test_unicode.py
index 38e758d..256057d 100644
--- a/tests/test_unicode.py
+++ b/tests/test_unicode.py
@@ -134,6 +134,15 @@ class UnicodeTests(PexpectTestCase.PexpectTestCase):
         p.sendeof()
         p.expect('▁▂▃▄▅▆▇█')
 
+    def test_readline_bin_echo(self):
+        # Test using readline() with spawnu objects. pexpect 3.2 had threw
+        # a TypeError when concatenating a bytestring to a unicode type.
+
+        # given,
+        child = pexpect.spawnu('echo', ['input', ])
+
+        # exercise,
+        assert child.readline() == 'input' + child.crlf
 
 if __name__ == '__main__':
     unittest.main()