Disabled sys._getframe() on Python interpreters that don't support it

CHANGES

@@ -3,6 +3,14 @@ Click Changelog
 
 This contains all major version changes between Click releases.
 
+Version 6.8
+-----------
+
+(bugfix release; yet to be released)
+
+- Disabled sys._getframes() on Python interpreters that don't support it. See
+  #728.
+
 Version 6.7
 -----------
 

click/_unicodefun.py

@@ -14,6 +14,8 @@
 
 def _find_unicode_literals_frame():
     import __future__
+    if not hasattr(sys, '_getframe'):  # not all Python implementations have it
+        return 0
     frm = sys._getframe(1)
     idx = 1
     while frm is not None:

click/decorators.py

@@ -235,7 +235,11 @@ def version_option(version=None, *param_decls, **attrs):
     :param others: everything else is forwarded to :func:`option`.
     """
     if version is None:
-        module = sys._getframe(1).f_globals.get('__name__')
+        if hasattr(sys, '_getframe'):
+            module = sys._getframe(1).f_globals.get('__name__')
+        else:
+            module = ''
+
     def decorator(f):
         prog_name = attrs.pop('prog_name', None)
         message = attrs.pop('message', '%(prog)s, version %(version)s')