Added tests and fix for multiparemeter contexts

See #174

pint/context.py

@@ -124,8 +124,15 @@ class Context(object):
                 if not val.imag:
                     return val.real
                 return val
-            defaults = dict((str(k), to_num(v))
-                            for k, v in _def_re.findall(defaults.strip('()')))
+
+            try:
+                _txt = defaults
+                defaults = (part.split('=') for part in defaults.strip('()').split(','))
+                defaults = dict((str(k).strip(), to_num(v))
+                                for k, v in defaults)
+            except (ValueError, TypeError):
+                raise ValueError('Could not parse Context definition defaults: %s', _txt)
+
             ctx = cls(name, aliases, defaults)
         else:
             ctx = cls(name, aliases)

pint/testsuite/test_contexts.py

@@ -560,6 +560,13 @@ class TestContexts(QuantityTestCase):
         self.assertEqual(set(c.funcs.keys()), set((a, b)))
         self._test_ctx(c)
 
+        s = ['@context(n=1, bla=2) longcontextname',
+             '[length] <-> 1 / [time]: n * c / value / bla']
+
+        c = Context.from_lines(s)
+        self.assertEqual(c.defaults, {'n': 1, 'bla': 2})
+        self.assertEqual(set(c.funcs.keys()), set((a, b)))
+
         # If the variable is not present in the definition, then raise an error
         s = ['@context(n=1) longcontextname',
              '[length] <-> 1 / [time]: c / value']