Value parse (#68)

* Fix parsing of value string to allow mismatched parenthesis inside [] brackets.

* Improve readability of value parse fix.

* Added additional test.

* Soft fail when fcntl is missing, fallback to default screen size.

tests/textfsm_test.py

@@ -70,6 +70,17 @@ def testFSMValue(self):
                       v.Parse,
                       'Value beer (boo)hoo)')
 
+    # Unbalanced parenthesis can exist if within square "[]" braces.
+    v = textfsm.TextFSMValue(options_class=textfsm.TextFSMOptions)
+    v.Parse('Value beer (boo[(]hoo)')
+    self.assertEqual(v.name, 'beer')
+    self.assertEqual(v.regex, '(boo[(]hoo)')
+
+    # Escaped braces don't count.
+    self.assertRaises(textfsm.TextFSMTemplateError,
+                      v.Parse,
+                      'Value beer (boo\[)\]hoo)')
+
     # String function.
     v = textfsm.TextFSMValue(options_class=textfsm.TextFSMOptions)
     v.Parse('Value Required beer (boo(hoo))')

textfsm/__init__.py

@@ -10,4 +10,4 @@
 """
 from textfsm.parser import *
 
-__version__ = '1.1.0'
+__version__ = '1.1.1'

textfsm/parser.py

@@ -313,8 +313,10 @@ def Parse(self, value):
       raise TextFSMTemplateError(
           "Invalid Value name '%s' or name too long." % self.name)
 
+    square_brackets = r'[^\]?\[[^]]*\]'
+    regex_without_brackets = re.sub(square_brackets, '', self.regex)
     if (not re.match(r'^\(.*\)$', self.regex) or
-        self.regex.count('(') != self.regex.count(')')):
+        regex_without_brackets.count('(') != regex_without_brackets.count(')')):
       raise TextFSMTemplateError(
           "Value '%s' must be contained within a '()' pair." % self.regex)
 

textfsm/terminal.py

@@ -22,7 +22,11 @@
 from __future__ import print_function
 from __future__ import unicode_literals
 
-import fcntl
+try:
+  # Import fails on Windows machines.
+  import fcntl
+except (ImportError, ModuleNotFoundError):
+  pass
 import getopt
 import os
 import re
@@ -173,7 +177,7 @@ def TerminalSize():
     with open(os.ctermid()) as tty_instance:
       length_width = struct.unpack(
           'hh', fcntl.ioctl(tty_instance.fileno(), termios.TIOCGWINSZ, '1234'))
-  except (IOError, OSError):
+  except (IOError, OSError, NameError):
     try:
       length_width = (int(os.environ['LINES']),
                       int(os.environ['COLUMNS']))