Updated IPythonWidget to use new prompt information. Initial prompt requests are not implemented.

IPython/frontend/qt/console/console_widget.py

@@ -878,12 +878,14 b' class ConsoleWidget(QtGui.QWidget):'
         # After inserting HTML, the text document "remembers" it's in "html
         # mode", which means that subsequent calls adding plain text will result
         # in unwanted formatting, lost tab characters, etc. The following code
-        # hacks around this behavior, which I consider to be a bug in Qt.
-        cursor.movePosition(QtGui.QTextCursor.Left, 
+        # hacks around this behavior, which I consider to be a bug in Qt, by
+        # (crudely) resetting the document's style state.
+        cursor.movePosition(QtGui.QTextCursor.Left,
                             QtGui.QTextCursor.KeepAnchor)
         if cursor.selection().toPlainText() == ' ':
             cursor.removeSelectedText()
-        cursor.movePosition(QtGui.QTextCursor.Right)
+        else:
+            cursor.movePosition(QtGui.QTextCursor.Right)
         cursor.insertText(' ', QtGui.QTextCharFormat())
         cursor.endEditBlock()
 

IPython/frontend/qt/console/frontend_widget.py

@@ -184,7 +184,7 b' class FrontendWidget(HistoryConsoleWidget, BaseFrontendMixin):'
                 self._process_execute_abort(msg)
 
             self._hidden = True
-            self._show_interpreter_prompt()
+            self._show_interpreter_prompt_for_reply(msg)
             self.executed.emit(msg)
 
     def _handle_input_request(self, msg):
@@ -335,6 +335,11 b' class FrontendWidget(HistoryConsoleWidget, BaseFrontendMixin):'
         """
         self._show_prompt('>>> ')
 
+    def _show_interpreter_prompt_for_reply(self, msg):
+        """ Shows a prompt for the interpreter given an 'execute_reply' message.
+        """
+        self._show_interpreter_prompt()
+
     #------ Signal handlers ----------------------------------------------------
 
     def _document_contents_change(self, position, removed, added):

IPython/frontend/qt/console/ipython_widget.py

@@ -10,6 +10,15 b' from IPython.core.usage import default_banner'
 from frontend_widget import FrontendWidget
 
 
+class IPythonPromptBlock(object):
+    """ An internal storage object for IPythonWidget.
+    """
+    def __init__(self, block, length, number):
+        self.block = block
+        self.length = length
+        self.number = number
+
+
 class IPythonWidget(FrontendWidget):
     """ A FrontendWidget for an IPython kernel.
     """
@@ -53,8 +62,7 b' class IPythonWidget(FrontendWidget):'
         #self._input_splitter = IPythonInputSplitter(input_mode='replace')
 
         # IPythonWidget protected variables.
-        self._previous_prompt_blocks = []
-        self._prompt_count = 0
+        self._previous_prompt_obj = None
 
         # Set a default editor and stylesheet.
         self.set_editor('default')
@@ -70,7 +78,6 b' class IPythonWidget(FrontendWidget):'
         prompt_number = omsg['content']['prompt_number']
         data = omsg['content']['data']
         self._append_html(self._make_out_prompt(prompt_number))
-        self._save_prompt_block()
         self._append_plain_text(data + '\n')
 
     #---------------------------------------------------------------------------
@@ -106,33 +113,45 b' class IPythonWidget(FrontendWidget):'
 
         self._append_html(traceback)
 
-    def _show_interpreter_prompt(self):
+    def _show_interpreter_prompt(self, number=None):
         """ Reimplemented for IPython-style prompts.
         """
-        # Update old prompt numbers if necessary.
-        previous_prompt_number = self._prompt_count
-        if previous_prompt_number != self._prompt_count:
-            for i, (block, length) in enumerate(self._previous_prompt_blocks):
-                if block.isValid():
-                    cursor = QtGui.QTextCursor(block)
-                    cursor.movePosition(QtGui.QTextCursor.Right,
-                                        QtGui.QTextCursor.KeepAnchor, length-1)
-                    if i == 0:
-                        prompt = self._make_in_prompt(previous_prompt_number)
-                    else:
-                        prompt = self._make_out_prompt(previous_prompt_number)
-                    self._insert_html(cursor, prompt)
-        self._previous_prompt_blocks = []
-
-        # Show a new prompt.
-        self._prompt_count += 1
-        self._show_prompt(self._make_in_prompt(self._prompt_count), html=True)
-        self._save_prompt_block()
+        # TODO: If a number was not specified, make a prompt number request.
+        if number is None:
+            number = 0
+
+        # Show a new prompt and save information about it so it can be updated
+        # later if its number needs to be re-written.
+        block = self._control.document().lastBlock()
+        self._show_prompt(self._make_in_prompt(number), html=True)
+        self._previous_prompt_obj = IPythonPromptBlock(
+            block.next(), len(self._prompt), number)
 
         # Update continuation prompt to reflect (possibly) new prompt length.
         self._set_continuation_prompt(
             self._make_continuation_prompt(self._prompt), html=True)
 
+    def _show_interpreter_prompt_for_reply(self, msg):
+        """ Reimplemented for IPython-style prompts.
+        """
+        # Update the old prompt number if necessary.
+        content = msg['content']
+        previous_prompt_number = content['prompt_number']
+        if self._previous_prompt_obj and \
+                self._previous_prompt_obj.number != previous_prompt_number:
+            block = self._previous_prompt_obj.block
+            if block.isValid():
+                cursor = QtGui.QTextCursor(block)
+                cursor.movePosition(QtGui.QTextCursor.Right,
+                                    QtGui.QTextCursor.KeepAnchor, 
+                                    self._previous_prompt_obj.length)
+                prompt = self._make_in_prompt(previous_prompt_number)
+                self._insert_html(cursor, prompt)
+            self._previous_prompt_obj = None
+
+        # Show a new prompt with the kernel's estimated prompt number.
+        self._show_interpreter_prompt(content['next_prompt']['prompt_number'])
+
     #---------------------------------------------------------------------------
     # 'IPythonWidget' interface
     #---------------------------------------------------------------------------
@@ -239,10 +258,3 b' class IPythonWidget(FrontendWidget):'
         """
         body = self.out_prompt % number
         return '<span class="out-prompt">%s</span>' % body
-
-    def _save_prompt_block(self):
-        """ Assuming a prompt has just been written at the end of the buffer,
-            store the QTextBlock that contains it and its length.
-        """
-        block = self._control.document().lastBlock()
-        self._previous_prompt_blocks.append((block, block.length()))