Change enums back to having None as the default value

src/calibre/gui2/custom_column_widgets.py

@@ -318,16 +318,14 @@ class Enumeration(Base):
                 QComboBox(parent)]
         w = self.widgets[1]
         vals = self.col_metadata['display']['enum_values']
+        w.addItem('')
         for v in vals:
             w.addItem(v)
 
     def initialize(self, book_id):
         val = self.db.get_custom(book_id, num=self.col_id, index_is_id=True)
-        if val is None:
-            # This really shouldn't happen
-            val = self.col_metadata['display']['enum_values'][0]
-        self.initial_val = val
         val = self.normalize_db_val(val)
+        self.initial_val = val
         idx = self.widgets[1].findText(val)
         if idx < 0:
             error_dialog(self.parent, '',
@@ -340,13 +338,21 @@ class Enumeration(Base):
         self.widgets[1].setCurrentIndex(idx)
 
     def setter(self, val):
-        if val is None:
-            val = ''
         self.widgets[1].setCurrentIndex(self.widgets[1].findText(val))
 
     def getter(self):
         return unicode(self.widgets[1].currentText())
 
+    def normalize_db_val(self, val):
+        if val is None:
+            val = ''
+        return val
+
+    def normalize_ui_val(self, val):
+        if not val:
+            val = None
+        return val
+
 widgets = {
         'bool' : Bool,
         'rating' : Rating,
@@ -597,7 +603,7 @@ class BulkEnumeration(BulkBase, Enumeration):
         dialog_shown = False
         for book_id in book_ids:
             val = self.db.get_custom(book_id, num=self.col_id, index_is_id=True)
-            if val not in self.col_metadata['display']['enum_values']:
+            if val and val not in self.col_metadata['display']['enum_values']:
                 if not dialog_shown:
                     error_dialog(self.parent, '',
                             _('The enumeration "{0}" contains invalid values '
@@ -620,6 +626,7 @@ class BulkEnumeration(BulkBase, Enumeration):
         w = self.widgets[1]
         vals = self.col_metadata['display']['enum_values']
         w.addItem('Do Not Change')
+        w.addItem('')
         for v in vals:
             w.addItem(v)
 
@@ -632,7 +639,10 @@ class BulkEnumeration(BulkBase, Enumeration):
         if val == ' nochange ':
             self.widgets[1].setCurrentIndex(0)
         else:
-            self.widgets[1].setCurrentIndex(self.widgets[1].findText(val))
+            if val is None:
+                self.widgets[1].setCurrentIndex(1)
+            else:
+                self.widgets[1].setCurrentIndex(self.widgets[1].findText(val))
 
     def commit(self, book_ids, notify=False):
         val = self.gui_val
@@ -640,12 +650,6 @@ class BulkEnumeration(BulkBase, Enumeration):
         if val != self.initial_val and val != ' nochange ':
             self.db.set_custom_bulk(book_ids, val, num=self.col_id, notify=notify)
 
-    def normalize_db_val(self, val):
-        if val is None:
-            # this really shouldn't happen
-            val = self.col_metadata['display']['enum_values'][0]
-        return val
-
 class RemoveTags(QWidget):
 
     def __init__(self, parent, values):

src/calibre/gui2/library/delegates.py

@@ -263,28 +263,22 @@ class CcEnumDelegate(QStyledItemDelegate): # {{{
         m = index.model()
         col = m.column_map[index.column()]
         editor = QComboBox(parent)
+        editor.addItem('')
         for v in m.custom_columns[col]['display']['enum_values']:
             editor.addItem(v)
         return editor
 
     def setModelData(self, editor, model, index):
         val = unicode(editor.currentText())
-        m = index.model()
+        if not val:
-        col = m.column_map[index.column()]
+            val = None
-        if val not in m.custom_columns[col]['display']['enum_values']:
-            # This shouldn't happen ...
-            print 'shouldnt happen'
-            val = m.custom_columns[col]['display']['enum_values'][0]
         model.setData(index, QVariant(val), Qt.EditRole)
 
     def setEditorData(self, editor, index):
         m = index.model()
         val = m.db.data[index.row()][m.custom_columns[m.column_map[index.column()]]['rec_index']]
         if val is None:
-            # This shouldn't happen
+            val = ''
-            m = index.model()
-            col = m.column_map[index.column()]
-            val = m.custom_columns[col]['display']['enum_values'][0]
         idx = editor.findText(val)
         if idx < 0:
             editor.setCurrentIndex(0)

src/calibre/gui2/library/models.py

@@ -724,6 +724,8 @@ class BooksModel(QAbstractTableModel): # {{{
             val = val if val else None
         elif typ == 'enumeration':
             val = unicode(value.toString()).strip()
+            if not val:
+                val = None
         elif typ == 'bool':
             val = value.toPyObject()
         elif typ == 'rating':
@@ -732,7 +734,7 @@ class BooksModel(QAbstractTableModel): # {{{
             val *= 2
         elif typ in ('int', 'float'):
             val = unicode(value.toString()).strip()
-            if val is None or not val:
+            if not val:
                 val = None
         elif typ == 'datetime':
             val = value.toDate()

src/calibre/gui2/preferences/create_custom_column.py

@@ -167,6 +167,10 @@ class CreateCustomColumn(QDialog, Ui_QCreateCustomColumn):
                 return self.simple_error('', _('You must enter at least one'
                     ' value for enumeration columns'))
             l = [v.strip() for v in unicode(self.enum_box.text()).split(',')]
+            for v in l:
+                if not v:
+                    return self.simple_error('', _('You cannot provide the empty '
+                    'value, as it is included by default'))
             for i in range(0, len(l)-1):
                 if l[i] in l[i+1:]:
                     return self.simple_error('', _('The value "{0}" is in the '

src/calibre/gui2/preferences/create_custom_column.ui

@@ -212,10 +212,9 @@
          <item>
           <widget class="QLineEdit" name="enum_box">
            <property name="toolTip">
-            <string>A comma-separated list of permitted values. You can specify
+            <string>A comma-separated list of permitted values. The empty value is always
-empty values by entering only the comma. For example, the list
+included, and is the default. For example, the list 'one,two,three' has
-',one,two,three' has 4 valid values, one of them empty. The first
+four values, the first of them being the empty value.</string>
-value in the list is the default.</string>
            </property>
            <property name="sizePolicy">
             <sizepolicy hsizetype="Maximum" vsizetype="Fixed">
@@ -231,7 +230,7 @@ value in the list is the default.</string>
             <string>Default: (nothing)</string>
            </property>
            <property name="toolTip">
-            <string>The first value entered will be the default value for this enumeration</string>
+            <string>The empty string is always the first value</string>
            </property>
           </widget>
          </item>

src/calibre/library/caches.py

@@ -254,12 +254,6 @@ class ResultCache(SearchQueryParser): # {{{
             if field_metadata[key]['datatype'] == 'composite':
                 self.composites.append((key, field_metadata[key]['rec_index']))
 
-        self.enumerations = []
-        for key in field_metadata:
-            if field_metadata[key]['datatype'] == 'enumeration':
-                self.enumerations.append((field_metadata[key]['display']['enum_values'][0],
-                                          field_metadata[key]['rec_index']))
-
     def __getitem__(self, row):
         return self._data[self._map_filtered[row]]
 
@@ -697,10 +691,6 @@ class ResultCache(SearchQueryParser): # {{{
                     mi = db.get_metadata(id, index_is_id=True)
                     for k,c in self.composites:
                         self._data[id][c] = mi.get(k, None)
-                if len(self.enumerations) > 0:
-                    for v,c in self.enumerations:
-                        if self._data[id][c] is None:
-                            self._data[id][c] = v
             except IndexError:
                 return None
         try:
@@ -721,10 +711,6 @@ class ResultCache(SearchQueryParser): # {{{
                 mi = db.get_metadata(id, index_is_id=True)
                 for k,c in self.composites:
                     self._data[id][c] = mi.get(k)
-            if len(self.enumerations) > 0:
-                for v,c in self.self._data[id][c]:
-                    if self._data[id][c] is None:
-                        self._data[id][c] =  v
         self._map[0:0] = ids
         self._map_filtered[0:0] = ids
 
@@ -754,10 +740,6 @@ class ResultCache(SearchQueryParser): # {{{
                     mi = db.get_metadata(item[0], index_is_id=True)
                     for k,c in self.composites:
                         item[c] = mi.get(k)
-                if len(self.enumerations) > 0:
-                    for v,c in self.enumerations:
-                        if item[c] is None:
-                            item[c] = v
 
         self._map = [i[0] for i in self._data if i is not None]
         if field is not None:

src/calibre/library/custom_columns.py

@@ -136,6 +136,12 @@ class CustomColumns(object):
                 x = bool(int(x))
             return x
 
+        def adapt_enum(x, d):
+            v = adapt_text(x, d)
+            if not v:
+                v = None
+            return v
+
         self.custom_data_adapters = {
                 'float': lambda x,d : x if x is None else float(x),
                 'int':   lambda x,d : x if x is None else int(x),
@@ -145,7 +151,7 @@ class CustomColumns(object):
                 'datetime' : adapt_datetime,
                 'text':adapt_text,
                 'series':adapt_text,
-                'enumeration': adapt_text
+                'enumeration': adapt_enum
         }
 
         # Create Tag Browser categories for custom columns
@@ -177,8 +183,6 @@ class CustomColumns(object):
             ans = ans.split('|') if ans else []
             if data['display'].get('sort_alpha', False):
                 ans.sort(cmp=lambda x,y:cmp(x.lower(), y.lower()))
-        elif data['datatype'] == 'enumeration' and ans is None:
-            ans = data['display']['enum_values'][0]
         return ans
 
     def get_custom_extra(self, idx, label=None, num=None, index_is_id=False):
@@ -442,8 +446,8 @@ class CustomColumns(object):
         val = self.custom_data_adapters[data['datatype']](val, data)
 
         if data['normalized']:
-            if data['datatype'] == 'enumeration' and \
+            if data['datatype'] == 'enumeration' and (
-                        val not in data['display']['enum_values']:
+                    val and val not in data['display']['enum_values']):
                 return None
             if not append or not data['is_multiple']:
                 self.conn.execute('DELETE FROM %s WHERE book=?'%lt, (id_,))