Preserve cursor position and _insert_plain_text()

Preserve position of cursor so ANSI commands such as \r that modify position will preserve the position they specifed over multiple calls, even if these calls are not all combined into one.

qtconsole/console_widget.py

@@ -1006,7 +1006,6 @@ def _append_custom(self, insert, input, before_prompt=False, *args, **kwargs):
         else:
             if insert != self._insert_plain_text:
                 self._flush_pending_stream()
-            cursor.movePosition(QtGui.QTextCursor.End)
 
         # Perform the insertion.
         result = insert(cursor, input, *args, **kwargs)
@@ -1660,10 +1659,7 @@ def _on_flush_pending_stream_timer(self):
         """ Flush the pending stream output and change the
         prompt position appropriately.
         """
-        cursor = self._control.textCursor()
-        cursor.movePosition(QtGui.QTextCursor.End)
         self._flush_pending_stream()
-        cursor.movePosition(QtGui.QTextCursor.End)
 
     def _flush_pending_stream(self):
         """ Flush out pending text into the widget. """
@@ -1674,7 +1670,7 @@ def _flush_pending_stream(self):
             text = self._get_last_lines_from_list(text, buffer_size)
         text = ''.join(text)
         t = time.time()
-        self._insert_plain_text(self._get_end_cursor(), text, flush=True)
+        self._insert_plain_text(self._control.textCursor(), text, flush=True)
         # Set the flush interval to equal the maximum time to update text.
         self._pending_text_flush_interval.setInterval(
             int(max(100, (time.time() - t) * 1000))
@@ -2086,6 +2082,9 @@ def _insert_plain_text(self, cursor, text, flush=False):
         """ Inserts plain text using the specified cursor, processing ANSI codes
             if enabled.
         """
+        if not text and not flush:
+            return
+
         should_autoscroll = self._viewport_at_end()
         # maximumBlockCount() can be different from self.buffer_size in
         # case input prompt is active.
@@ -2123,7 +2122,7 @@ def _insert_plain_text(self, cursor, text, flush=False):
                             cursor.select(QtGui.QTextCursor.Document)
                             remove = True
                         if act.area == 'line':
-                            if act.erase_to == 'all': 
+                            if act.erase_to == 'all':
                                 cursor.select(QtGui.QTextCursor.LineUnderCursor)
                                 remove = True
                             elif act.erase_to == 'start':
@@ -2137,7 +2136,7 @@ def _insert_plain_text(self, cursor, text, flush=False):
                                     QtGui.QTextCursor.EndOfLine,
                                     QtGui.QTextCursor.KeepAnchor)
                                 remove = True
-                        if remove: 
+                        if remove:
                             nspace=cursor.selectionEnd()-cursor.selectionStart() if fill else 0
                             cursor.removeSelectedText()
                             if nspace>0: cursor.insertText(' '*nspace) # replace text by space, to keep cursor position as specified
@@ -2181,11 +2180,12 @@ def _insert_plain_text(self, cursor, text, flush=False):
                         remain = cursor2.position() - pos    # number of characters until end of line
                         n=len(substring)
                         swallow = min(n, remain)             # number of character to swallow
-                        cursor.setPosition(pos+swallow,QtGui.QTextCursor.KeepAnchor)
+                        cursor.setPosition(pos + swallow, QtGui.QTextCursor.KeepAnchor)
                     cursor.insertText(substring,format)
         else:
             cursor.insertText(text)
         cursor.endEditBlock()
+        self._control.setTextCursor(cursor)
 
         if should_autoscroll:
             self._scroll_to_end()