Cleanup previous PR

I dont think we need to enforce unique column titles. If a user wants to
have columns with the same titles, that's up to them. Also avoids the
performance penalty.

resources/default_tweaks.py

@@ -575,16 +575,10 @@ allow_template_database_functions_in_composites = False
 # takes a glob pattern allowing a single entry to match multiple URL types.
 openers_by_scheme = {}
 
-#: Change standard column heading text to some value
-# Use the dictionary below to change a column heading. The format of the
-# dictionary is
-#   {lookup_name: new_heading, ...}
-# The new_heading must be unique: no two columns can have the same heading.
-# This tweak works only with standard columns: it cannot be used to change
-# the heading for a custom column. If a custom column has the same heading as
-# one provided here then a number will appended to the custom column's heading
-# to make it unique.
-#
+#: Change standard column names
+# Use the dictionary below to change a column name.
+# This tweak works only with standard columns, it cannot be used to change
+# the heading for a custom column.
 # Example:
-#   alternate_column_headings = {'authors':'Writers', 'size':'MBytes'}
-alternate_column_headings = {}
+#   alternate_column_names = {'authors':'Writers', 'size':'MBytes'}
+alternate_column_names = {}

src/calibre/gui2/dialogs/quickview.py

@@ -342,7 +342,7 @@ class Quickview(QDialog, Ui_Quickview):
         a = m.addAction(self.select_book_icon, _('Select this book in the library'),
                                 partial(self.select_book, book_id))
         a.setEnabled(book_displayed)
-        m.addAction(_('Open a locked book details window for this book'),
+        m.addAction(_('Open a locked Book details window for this book'),
                     partial(self.show_book_details, book_id))
         m.addAction(self.search_icon, _('Find item in the library'),
                         partial(self.do_search, follow_library_view=False))

src/calibre/gui2/library/views.py

@@ -967,7 +967,6 @@ class BooksView(QTableView):  # {{{
                     injected = False
                     for f in ('last_modified', 'languages', 'formats', 'id', 'path'):
                         if not ans.get(f+'_injected', False):
-                            print('injecting', f)
                             injected = True
                             ans[f+'_injected'] = True
                             hc = ans.get('hidden_columns', [])

src/calibre/library/field_metadata.py

@@ -5,7 +5,6 @@ Created on 25 May 2010
 '''
 
 import traceback
-import sys
 from collections import OrderedDict
 
 from calibre.utils.config_base import tweaks
@@ -396,6 +395,7 @@ class FieldMetadata:
 
     # search labels that are not db columns
     search_items = ['all', 'search', 'vl', 'template']
+    custom_field_prefix = '#'
     __calibre_serializable__ = True
 
     def __init__(self):
@@ -412,22 +412,18 @@ class FieldMetadata:
             self._tb_cats[k]['display'] = {}
             self._tb_cats[k]['is_editable'] = True
             self._add_search_terms_to_map(k, v['search_terms'])
-        alternate_headings = tweaks.get('alternate_column_headings', {})
-        if alternate_headings:
-            existing_headings = {k['name'] for k in self._tb_cats.values() if k['name']}
-            for k,v in alternate_headings.items():
-                if k in self._tb_cats.keys():
-                    v = self.get_unique_field_heading(v)
-                    existing_headings.discard(self._tb_cats[k]['name'])
-                    existing_headings.add(v)
+        try:
+            for k, v in tweaks['alternate_column_names'].items():
+                if k in self._tb_cats and not self.is_custom_field(k):
                     self._tb_cats[k]['name'] = v
+        except Exception:
+            traceback.print_exc()
         self._tb_cats['timestamp']['display'] = {
                         'date_format': tweaks['gui_timestamp_display_format']}
         self._tb_cats['pubdate']['display'] = {
                         'date_format': tweaks['gui_pubdate_display_format']}
         self._tb_cats['last_modified']['display'] = {
                         'date_format': tweaks['gui_last_modified_display_format']}
-        self.custom_field_prefix = '#'
         self.get = self._tb_cats.get
 
     def __getitem__(self, key):
@@ -464,10 +460,6 @@ class FieldMetadata:
     def __ne__(self, other):
         return not self.__eq__(other)
 
-    def set_field_heading(self, key, heading):
-        if key in self._tb_cats.keys():
-            self._tb_cats[key]['name'] = heading
-
     def sortable_field_keys(self):
         return [k for k in self._tb_cats.keys()
                 if self._tb_cats[k]['kind']=='field' and
@@ -574,18 +566,6 @@ class FieldMetadata:
             l[k] = self._tb_cats[k]
         return l
 
-    def get_unique_field_heading(self, name):
-        # Verify column heading is unique. Can only happen if the tweak is set
-        if tweaks.get('alternate_column_headings', {}):
-            existing_names = {icu_lower(c['name']) for c in self._tb_cats.values() if c['name'] is not None}
-            t = icu_lower(name)
-            if t in existing_names:
-                for i in range(1, sys.maxsize):
-                    if (t + '_' + str(i)) not in existing_names:
-                        name = name + '_' + str(i)
-                        break
-        return name
-
     def add_custom_field(self, label, table, column, datatype, colnum, name,
                          display, is_editable, is_multiple, is_category,
                          is_csp=False):
@@ -594,7 +574,6 @@ class FieldMetadata:
             raise ValueError('Duplicate custom field [%s]'%(label))
         if datatype not in self.VALID_DATA_TYPES:
             raise ValueError('Unknown datatype %s for field %s'%(datatype, key))
-        name = self.get_unique_field_heading(name)
         self._tb_cats[key] = {'table':table,       'column':column,
                              'datatype':datatype,  'is_multiple':is_multiple,
                              'kind':'field',       'name':name,