Use the new traceback module for nicer tracebacks

src/pyj/book_list/book_details.pyj

@@ -1,6 +1,7 @@
 # vim:fileencoding=utf-8
 # License: GPL v3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
 
+import traceback
 from ajax import ajax
 from book_list.globals import get_current_query
 from book_list.theme import get_font_size
@@ -241,10 +242,9 @@ def render_metadata(mi, interface_data, table, field_list=None):
             continue
         try:
             process_field(field, fm)
-        except Exception as err:
+        except Exception:
             print('Failed to render metadata field: ' + field)
-            print(err.toString())
+            traceback.print_exc()
-            print(err.stack)
 
     for i, field in enumerate(sorted(comments)):
         comment = comments[field]

src/pyj/book_list/boss.pyj

@@ -1,6 +1,7 @@
 # vim:fileencoding=utf-8
 # License: GPL v3 Copyright: 2015, Kovid Goyal <kovid at kovidgoyal.net>
 
+import traceback
 from ajax import encode_query
 from dom import set_css
 from elementmaker import E
@@ -76,8 +77,8 @@ class Boss:
             fname = script_url.rpartition('/')[-1] or script_url
             msg = msg + '<br><span style="font-size:smaller">' + 'Error at {}:{}:{}'.format(fname, line_number, column_number or '') + '</span>'
             details = ''
-            if error_object and error_object.stack:
+            if error_object:
-                details = error_object.stack
+                details = traceback.format_exception(error_object).join('')
             error_dialog(_('Unhandled error'), msg, details)
             return True
         except:

src/pyj/book_list/ui.pyj

@@ -1,6 +1,7 @@
 # vim:fileencoding=utf-8
 # License: GPL v3 Copyright: 2015, Kovid Goyal <kovid at kovidgoyal.net>
 
+import traceback
 from book_list.globals import get_boss, get_session_data
 from book_list.search import SearchPanel
 from book_list.top_bar import TopBar
@@ -196,7 +197,7 @@ class UI:
                 data = JSON.parse(xhr.responseText)
                 boss.change_books(data)
             except Exception as err:
-                return error_dialog(_('Could not change library'), err + '', details=err.stack)
+                return error_dialog(_('Could not change library'), err + '', details=traceback.format_exc())
             self.show_panel(self.ROOT_PANEL)
             window.scrollTo(0, 0)
         elif end_type is not 'abort':

src/pyj/book_list/views.pyj

@@ -1,6 +1,7 @@
 # vim:fileencoding=utf-8
 # License: GPL v3 Copyright: 2015, Kovid Goyal <kovid at kovidgoyal.net>
 
+import traceback
 from ajax import ajax_send
 from dom import set_css, build_rule, clear
 from elementmaker import E
@@ -145,8 +146,8 @@ class BooksView:
                     raise Exception('No books ids object in search result from server')
                 self.render_ids(data.search_result.book_ids)
                 self.interface_data.search_result = data.search_result
-            except Exception as err:
+            except Exception:
-                error_dialog(_('Could not get more books'), _('Server returned an invalid response'), err.stack or err.toString())
+                error_dialog(_('Could not get more books'), _('Server returned an invalid response'), traceback.format_exc())
         elif end_type is not 'abort':
             error_dialog(_('Could not get more books'), xhr.error_html)
 
@@ -230,7 +231,7 @@ class BooksView:
                 data = JSON.parse(xhr.responseText)
                 boss.change_books(data)
             except Exception as err:
-                return error_dialog(_('Could not change sort order'), err + '', details=err.stack)
+                return error_dialog(_('Could not change sort order'), err + '', details=traceback.format_exc())
             boss.ui.show_panel(boss.ui.ROOT_PANEL)
             window.scrollTo(0, 0)
         elif end_type is not 'abort':
@@ -251,7 +252,7 @@ class BooksView:
                 data = JSON.parse(xhr.responseText)
                 boss.change_books(data)
             except Exception as err:
-                return error_dialog(_('Could not change search query'), err + '', details=err.stack)
+                return error_dialog(_('Could not change search query'), err + '', details=traceback.format_exc())
             self.update_fetching_status()
             ed = xhr.extra_data_for_callback
             boss.ui.show_panel(ed.panel_to_show or boss.ui.ROOT_PANEL, push_state=ed.push_state)

src/pyj/read_book/iframe.pyj

@@ -2,6 +2,7 @@
 # License: GPL v3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
 from __python__ import bound_methods
 
+import traceback
 from aes import GCM
 from gettext import install
 from read_book.globals import set_boss, set_current_spine_item, current_layout_mode, current_spine_item
@@ -45,7 +46,7 @@ class Boss:
             except Exception as e:
                 console.log('Error in iframe message handler:')
                 console.log(e)
-                self.send_message('error', details=e.stack, msg=e.toString())
+                self.send_message('error', details=traceback.format_exc(), msg=e.toString())
         else:
             print('Unknown action in message to iframe from parent: ' + data.action)
 

src/pyj/read_book/ui.pyj

@@ -2,6 +2,7 @@
 # License: GPL v3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
 # globals: __RENDER_VERSION__
 
+import traceback
 from ajax import ajax, encode_query
 from elementmaker import E
 from gettext import gettext as _
@@ -138,10 +139,10 @@ class ReadUI:
                                 xhr.error_html)
         try:
             manifest = JSON.parse(xhr.responseText)
-        except Exception as err:
+        except Exception:
             return self.show_error(_('Failed to load book manifest'),
                 _('The manifest for {title} is not valid').format(title=self.current_metadata.title),
-                                err.stack or err.toString())
+                traceback.format_exc())
         if manifest.version is not RENDER_VERSION:
             return self.show_error(_('calibre upgraded!'), _(
                 'A newer version of calibre is available, please click the reload button in your browser.'))