Factor out BoolFacet from StarredFacet and add BlankFacet.

google/refine.py

@@ -81,22 +81,34 @@ class TextFacet(Facet):
         return self
 
 
-class StarredFacet(TextFacet):
-    def __init__(self, selection=None):
+class BoolFacet(TextFacet):
+    def __init__(self, column, expression=None, selection=None):
         if selection is not None and not isinstance(selection, bool):
             raise ValueError('selection must be True or False.')
+        if expression is None:
+            raise ValueError('Missing expression')
+        super(BoolFacet, self).__init__(column,
+            expression=expression, selection=selection)
+
+
+class StarredFacet(BoolFacet):
+    def __init__(self, selection=None):
         super(StarredFacet, self).__init__('',
             expression='row.starred', selection=selection)
 
 
-class FlaggedFacet(TextFacet):
+class FlaggedFacet(BoolFacet):
     def __init__(self, selection=None):
-        if selection is not None and not isinstance(selection, bool):
-            raise ValueError('selection must be True or False.')
         super(FlaggedFacet, self).__init__('',
             expression='row.flagged', selection=selection)
 
 
+class BlankFacet(BoolFacet):
+    def __init__(self, column, selection=None):
+        super(BlankFacet, self).__init__(column,
+            expression='isBlank(value)', selection=selection)
+
+
 # Capitalize 'From' to get around python's reserved word.
 class NumericFacet(Facet):
     def __init__(self, column, From=None, to=None, select_blank=True, select_error=True, select_non_numeric=True, select_numeric=True, **options):

google/test/test_refine.py

@@ -11,7 +11,8 @@ import sys
 import os
 import unittest
 from google.refine import REFINE_HOST, REFINE_PORT
-from google.refine import NumericFacet, TextFacet, StarredFacet, Engine
+from google.refine import NumericFacet, TextFacet
+from google.refine import BlankFacet, StarredFacet, Engine
 from google.refine import RefineServer, Refine, RefineProject
 from google.refine import to_camel, from_camel
 
@@ -300,8 +301,7 @@ class TutorialTestDuplicateDetection(RefineTestCase):
         emails = [1 if r['email'] else 0 for r in response.rows]
         self.assertEqual(emails, [1, 0, 1, 1, 1, 0, 0, 1, 1, 0])
         # {12}
-        blank_facet = TextFacet('email', expression='isBlank(value)',
-                                selection=True)
+        blank_facet = BlankFacet('email', selection=True)
         # {13}
         response = self.project.remove_rows(blank_facet)
         self.assertTrue('Remove 4 rows' in
@@ -467,8 +467,7 @@ class TutorialTestTransposeVariableNumbeOfRowsIntoColumns(RefineTestCase):
         # {26}
         self.project.engine.mode = 'row-based'
         # {27}
-        blank_facet = TextFacet('First Line', expression='isBlank(value)',
-                                selection=True)
+        blank_facet = BlankFacet('First Line', selection=True)
         response = self.project.remove_rows(blank_facet)
         self.assertEqual('Remove 14 rows',
                          response['historyEntry']['description'])