Fix bug when case sensitivity is explicitly turned off.

When passing False for case sensitivity, it would fall into the logic
to automatically determine whether case sensitivity is desired
based on the appearance of capitals.

Filter.py

@@ -18,7 +18,7 @@ class GrepFilter(Filter):
     def __init__(self, p_expression, p_case_sensitive=None):
         self.expression = p_expression
 
-        if p_case_sensitive:
+        if p_case_sensitive != None:
             self.case_sensitive = p_case_sensitive
         else:
             # only be case sensitive when the expression contains at least one

test/FilterTest.py

@@ -73,3 +73,14 @@ class FilterTest(unittest.TestCase):
 
         self.assertEquals(todolist_to_string(filtered_todos), \
             todolist_to_string(reference))
+
+    def test_filter8(self):
+        """ Test case sensitive match (forced, with lowercase). """
+        todos = load_file('data/FilterTest1.txt')
+        grep = Filter.GrepFilter('+Project', False)
+
+        filtered_todos = grep.filter(todos)
+        reference = load_file('data/FilterTest1a-result.txt')
+
+        self.assertEquals(todolist_to_string(filtered_todos), \
+            todolist_to_string(reference))