Add format strings to int and float custom columns

src/calibre/ebooks/metadata/book/base.py

@@ -628,6 +628,12 @@ class Metadata(object):
                 res = _('Yes') if res else _('No')
             elif datatype == 'rating':
                 res = res/2.0
+            elif datatype in ['int', 'float']:
+                try:
+                    fmt = cmeta['display'].get('number_format', None)
+                    res = fmt.format(res)
+                except:
+                    pass
             return (name, unicode(res), orig_res, cmeta)
 
         # convert top-level ids into their value

src/calibre/gui2/library/models.py

@@ -623,7 +623,12 @@ class BooksModel(QAbstractTableModel): # {{{
                 return None
             return QVariant(text)
 
-        def number_type(r, idx=-1):
+        def number_type(r, idx=-1, fmt=None):
+            if fmt is not None:
+                try:
+                    return QVariant(fmt.format(self.db.data[r][idx]))
+                except:
+                    pass
             return QVariant(self.db.data[r][idx])
 
         self.dc = {
@@ -674,7 +679,8 @@ class BooksModel(QAbstractTableModel): # {{{
                             bool_cols_are_tristate=
                                 self.db.prefs.get('bools_are_tristate'))
             elif datatype in ('int', 'float'):
-                self.dc[col] = functools.partial(number_type, idx=idx)
+                fmt = self.custom_columns[col]['display'].get('number_format', None)
+                self.dc[col] = functools.partial(number_type, idx=idx, fmt=fmt)
             elif datatype == 'datetime':
                 self.dc[col] = functools.partial(datetime_type, idx=idx)
             elif datatype == 'bool':

src/calibre/gui2/preferences/create_custom_column.py

@@ -127,6 +127,9 @@ class CreateCustomColumn(QDialog, Ui_QCreateCustomColumn):
         elif ct == 'enumeration':
             self.enum_box.setText(','.join(c['display'].get('enum_values', [])))
             self.enum_colors.setText(','.join(c['display'].get('enum_colors', [])))
+        elif ct in ['int', 'float']:
+            if c['display'].get('number_format', None):
+                self.number_format_box.setText(c['display'].get('number_format', ''))
         self.datatype_changed()
         if ct in ['text', 'composite', 'enumeration']:
             self.use_decorations.setChecked(c['display'].get('use_decorations', False))
@@ -171,6 +174,7 @@ class CreateCustomColumn(QDialog, Ui_QCreateCustomColumn):
             col_type = None
         for x in ('box', 'default_label', 'label'):
             getattr(self, 'date_format_'+x).setVisible(col_type == 'datetime')
+            getattr(self, 'number_format_'+x).setVisible(col_type in ['int', 'float'])
         for x in ('box', 'default_label', 'label', 'sort_by', 'sort_by_label',
                   'make_category'):
             getattr(self, 'composite_'+x).setVisible(col_type in ['composite', '*composite'])
@@ -267,6 +271,11 @@ class CreateCustomColumn(QDialog, Ui_QCreateCustomColumn):
             display_dict = {'enum_values': l, 'enum_colors': c}
         elif col_type == 'text' and is_multiple:
             display_dict = {'is_names': self.is_names.isChecked()}
+        elif col_type in ['int', 'float']:
+            if unicode(self.number_format_box.text()).strip():
+                display_dict = {'number_format':unicode(self.number_format_box.text()).strip()}
+            else:
+                display_dict = {'number_format': None}
 
         if col_type in ['text', 'composite', 'enumeration'] and not is_multiple:
             display_dict['use_decorations'] = self.use_decorations.checkState()

src/calibre/gui2/preferences/create_custom_column.ui

@@ -171,6 +171,20 @@ Everything else will show nothing.</string>
            </property>
           </widget>
          </item>
+         <item>
+          <widget class="QLineEdit" name="number_format_box">
+           <property name="sizePolicy">
+            <sizepolicy hsizetype="Maximum" vsizetype="Fixed">
+             <horstretch>0</horstretch>
+             <verstretch>0</verstretch>
+            </sizepolicy>
+           </property>
+           <property name="toolTip">
+            <string>&lt;p&gt;Use 0 (a zero) for the field name. Example: {0:0>5.2f} gives a 5-digit floating point number, 2 digits after the decimal point, with leading zeros
+            </string>
+           </property>
+          </widget>
+         </item>
          <item>
           <widget class="QLabel" name="date_format_default_label">
            <property name="toolTip">
@@ -181,6 +195,19 @@ Everything else will show nothing.</string>
            </property>
           </widget>
          </item>
+         <item>
+          <widget class="QLabel" name="number_format_default_label">
+           <property name="toolTip">
+            <string>&lt;p&gt;Example: ${0:,.2f} gives floating point number prefixed by a dollar sign, 2 digits after the decimal point, with thousands separated by commas</string>
+           </property>
+           <property name="text">
+            <string>&lt;p&gt;Default: Not formatted. For format language details see &lt;a href="http://docs.python.org/library/string.html#format-string-syntax"&gt;the python documentation&lt;/a&gt;</string>
+           </property>
+           <property name="openExternalLinks">
+            <bool>true</bool>
+           </property>
+          </widget>
+         </item>
         </layout>
        </item>
        <item row="4" column="0">
@@ -193,6 +220,16 @@ Everything else will show nothing.</string>
          </property>
         </widget>
        </item>
+       <item row="4" column="0">
+        <widget class="QLabel" name="number_format_label">
+         <property name="text">
+          <string>Format for &amp;numbers</string>
+         </property>
+         <property name="buddy">
+          <cstring>number_format_box</cstring>
+         </property>
+        </widget>
+       </item>
        <item row="5" column="0">
         <widget class="QLabel" name="composite_label">
          <property name="text">