Make jumping to character locations robust against file edits

src/calibre/ebooks/oeb/polish/report.py

@@ -7,7 +7,7 @@ __license__ = 'GPL v3'
 __copyright__ = '2015, Kovid Goyal <kovid at kovidgoyal.net>'
 
 import posixpath, os
-from collections import namedtuple, defaultdict
+from collections import namedtuple, defaultdict, Counter
 
 from calibre.ebooks.oeb.polish.container import OEB_DOCS, OEB_STYLES, OEB_FONTS
 from calibre.ebooks.oeb.polish.spell import get_all_words
@@ -93,19 +93,29 @@ def word_data(container, book_locale):
     count, words = get_all_words(container, book_locale, get_word_count=True)
     return (count, tuple(Word(i, word, locale, v) for i, ((word, locale), v) in enumerate(words.iteritems())))
 
-Char = namedtuple('Char', 'id char codepoint usage')
+Char = namedtuple('Char', 'id char codepoint usage count')
 
 def char_data(container):
-    chars = defaultdict(list)
+    chars = defaultdict(set)
+    counter = Counter()
+    def count(codepoint):
+        counter[codepoint] += 1
+
     for name, is_linear in container.spine_names:
         if container.mime_map.get(name) not in OEB_DOCS:
             continue
         raw = container.raw_data(name)
-        for i, codepoint in enumerate(ord_string(raw)):
+        counts = Counter(ord_string(raw))
-            chars[codepoint].append(Location(name, character_offset=i))
+        counter.update(counts)
+        for codepoint in counts:
+            chars[codepoint].add(name)
+
+    nmap = {n:i for i, (n, l) in enumerate(container.spine_names)}
+    def sort_key(name):
+        return nmap.get(name, len(nmap)), numeric_sort_key(name)
 
     for i, (codepoint, usage) in enumerate(chars.iteritems()):
-        yield Char(i, safe_chr(codepoint), codepoint, sort_locations(container, usage))
+        yield Char(i, safe_chr(codepoint), codepoint, sorted(usage, key=sort_key), counter[codepoint])
 
 def gather_data(container, book_locale):
     data =  {'files':tuple(file_data(container))}

src/calibre/gui2/tweak_book/boss.py

@@ -1244,10 +1244,11 @@ class Boss(QObject):
         self.gui.central.show_editor(editors[name])
         editors[name].set_focus()
 
-    def edit_file_requested(self, name, syntax, mime):
+    def edit_file_requested(self, name, syntax=None, mime=None):
         if name in editors:
             self.gui.central.show_editor(editors[name])
             return editors[name]
+        mime = mime or current_container().mime_map.get(name, guess_type(name))
         syntax = syntax or syntax_from_mime(name, mime)
         if not syntax:
             return error_dialog(

src/calibre/gui2/tweak_book/reports.py

@@ -20,7 +20,6 @@ from PyQt5.Qt import (
     QStyledItemDelegate, QModelIndex, QRect, QStyle, QPalette, QTimer, QMenu)
 
 from calibre import human_readable, fit_image
-from calibre.ebooks.oeb.polish.container import guess_type
 from calibre.ebooks.oeb.polish.report import gather_data
 from calibre.gui2 import error_dialog, question_dialog
 from calibre.gui2.tweak_book import current_container, tprefs, dictionaries
@@ -276,8 +275,7 @@ class Jump(object):  # {{{
         if boss is None:
             return
         name = loc.name
-        mt = current_container().mime_map.get(name, guess_type(name))
+        editor = boss.edit_file_requested(name)
-        editor = boss.edit_file_requested(name, None, mt)
         if editor is None:
             return
         editor = editor.editor
@@ -290,10 +288,6 @@ class Jump(object):  # {{{
             editor.setTextCursor(c)
             if loc.text_on_line is not None:
                 editor.find(regex.compile(regex.escape(loc.text_on_line)))
-        elif loc.character_offset is not None:
-            c = editor.textCursor()
-            c.setPosition(loc.character_offset + 1)  # put cursor after the character
-            editor.setTextCursor(c)
 
 jump = Jump()  # }}}
 
@@ -557,7 +551,7 @@ class CharsModel(FileCollection):
             if col == 2:
                 return ('U+%04X' if entry.codepoint < 0x10000 else 'U+%06X') % entry.codepoint
             if col == 3:
-                return type('')(len(entry.usage))
+                return type('')(entry.count)
         if role == Qt.UserRole:
             try:
                 return self.files[index.row()]
@@ -595,10 +589,37 @@ class CharsWidget(QWidget):
     def double_clicked(self, index):
         entry = index.data(Qt.UserRole)
         if entry is not None:
-            jump((id(self), entry.id), entry.usage)
+            self.find_next_location(entry)
 
     def save(self):
         save_state('chars-table', bytearray(self.chars.horizontalHeader().saveState()))
+
+    def find_next_location(self, entry):
+        from calibre.gui2.tweak_book.boss import get_boss
+        boss = get_boss()
+        if boss is None:
+            return
+        files = entry.usage
+        current_editor_name = boss.currently_editing
+        if current_editor_name not in files:
+            current_editor_name = None
+        else:
+            idx = files.index(current_editor_name)
+            before, after = files[:idx], files[idx+1:]
+            files = [current_editor_name] + after + before + [current_editor_name]
+
+        pat = regex.compile(regex.escape(entry.char))
+        for file_name in files:
+            from_cursor = False
+            if file_name == current_editor_name:
+                from_cursor = True
+                current_editor_name = None
+            ed = boss.edit_file_requested(file_name)
+            if ed.editor.find(pat, complete=not from_cursor):
+                boss.show_editor(file_name)
+                return True
+        return False
+
 # }}}
 
 # Wrapper UI {{{