Add "equal to any of" verb for string-type grid filters

tailbone/grids/filters.py

@@ -331,6 +331,38 @@ class AlchemyGridFilter(GridFilter):
             self.column != self.encode_value(value),
         ))
 
+    def filter_equal_any_of(self, query, value):
+        """
+        This filter expects "multiple values" separated by newline
+        character, and will add an "OR" condition with each value
+        being checked separately.  For instance if the user submits a
+        "value" like this:
+
+        .. code-block:: none
+
+           foo bar
+           baz
+
+        This will result in SQL condition like this:
+
+        .. code-block:: sql
+
+           name = 'foo bar' OR name = 'baz'
+        """
+        if not value:
+            return query
+
+        values = value.split('\n')
+        values = [value for value in values if value]
+        if not values:
+            return query
+
+        conditions = []
+        for value in values:
+            conditions.append(self.column == self.encode_value(value))
+
+        return query.filter(sa.or_(*conditions))
+
     def filter_is_null(self, query, value):
         """
         Filter data with an 'IS NULL' query.  Note that this filter does not
@@ -430,7 +462,7 @@ class AlchemyStringFilter(AlchemyGridFilter):
         """
         return ['contains', 'does_not_contain',
                 'contains_any_of',
-                'equal', 'not_equal',
+                'equal', 'not_equal', 'equal_any_of',
                 'is_empty', 'is_not_empty',
                 'is_null', 'is_not_null',
                 'is_empty_or_null',