some more work

IPython/terminal/interactiveshell.py

@@ -87,6 +87,14 b' else:'
 
 _use_simple_prompt = ('IPY_TEST_SIMPLE_PROMPT' in os.environ) or (not _is_tty)
 
+def black_reformat_handler(text_before_cursor):
+    import black
+    formatted_text = black.format_str(text_before_cursor, mode=black.FileMode())
+    if not text_before_cursor.endswith('\n') and formatted_text.endswith('\n'):
+       formatted_text = formatted_text[:-1]
+    return formatted_text
+
+
 class TerminalInteractiveShell(InteractiveShell):
     space_for_menu = Integer(6, help='Number of line at the bottom of the screen '
                                      'to reserve for the completion menu'
@@ -120,6 +128,11 b' class TerminalInteractiveShell(InteractiveShell):'
         help="Shortcut style to use at the prompt. 'vi' or 'emacs'.",
     ).tag(config=True)
 
+    autoformatter = Unicode(None,
+        help="Autoformatter to reformat Terminal code. Can be `'black'` or `None`",
+        allow_none=True
+    ).tag(config=True)
+
     mouse_support = Bool(False,
         help="Enable mouse support in the prompt\n(Note: prevents selecting text with the mouse)"
     ).tag(config=True)
@@ -150,6 +163,16 b' class TerminalInteractiveShell(InteractiveShell):'
         if self.pt_app:
             self.pt_app.editing_mode = u_mode
 
+    @observe('autoformatter')
+    def _autoformatter_changed(self, change):
+        formatter = change.new
+        if formatter is None:
+            self.reformat_handler = lambda x:x
+        elif formatter == 'black':
+            self.reformat_handler = black_reformat_handler
+        else:
+            raise ValueError
+
     @observe('highlighting_style')
     @observe('colors')
     def _highlighting_style_changed(self, change):
@@ -246,6 +269,7 b' class TerminalInteractiveShell(InteractiveShell):'
         self.display_formatter.ipython_display_formatter.enabled = False
 
     def init_prompt_toolkit_cli(self):
+        self.reformat_handler = lambda x:x
         if self.simple_prompt:
             # Fall back to plain non-interactive output for tests.
             # This is very limited.

IPython/terminal/shortcuts.py

@@ -44,6 +44,15 b' def create_ipython_shortcuts(shell):'
                             & insert_mode
                         ))(return_handler)
 
+    def reformat_and_execute(event):
+        reformat_text_before_cursor(event.current_buffer, event.current_buffer.document, shell)
+        event.current_buffer.validate_and_handle()
+
+    kb.add('escape', 'enter', filter=(has_focus(DEFAULT_BUFFER)
+                            & ~has_selection
+                            & insert_mode
+                                      ))(reformat_and_execute)
+
     kb.add('c-\\')(force_exit)
 
     kb.add('c-p', filter=(vi_insert_mode & has_focus(DEFAULT_BUFFER))
@@ -86,24 +95,21 b' def create_ipython_shortcuts(shell):'
     return kb
 
 
+def reformat_text_before_cursor(buffer, document, shell):
+    text = buffer.delete_before_cursor(len(document.text[:document.cursor_position]))
+    try:
+        formatted_text = shell.reformat_handler(text)
+        buffer.insert_text(formatted_text)
+    except Exception as e:
+        buffer.insert_text(text)
+
+
 def newline_or_execute_outer(shell):
 
-    import black
     def newline_or_execute(event):
         """When the user presses return, insert a newline or execute the code."""
         b = event.current_buffer
         d = b.document
-        def try_reformat():
-            try:
-                tbc = b.delete_before_cursor(len(d.text[:d.cursor_position]))
-                fmt= black.format_str(tbc, mode=black.FileMode())
-                if not tbc.endswith('\n') and fmt.endswith('\n'):
-                    fmt = fmt[:-1]
-                b.insert_text(fmt)
-                #print(f'no eexc |{tbc[-1]}|,|{d.text[-1]}|, |{fmt[-3:-1]}|')
-            except Exception as e:
-                b.insert_text(tbc)
-
 
         if b.complete_state:
             cc = b.complete_state.current_completion
@@ -120,7 +126,11 b' def newline_or_execute_outer(shell):'
         else:
             check_text = d.text[:d.cursor_position]
         status, indent = shell.check_complete(check_text)
-
+       
+        # if all we have after the cursor is whitespace: reformat current text
+        # before cursor
+        if d.text[d.cursor_position:].isspace():
+            reformat_text_before_cursor(b, d, shell)
         if not (d.on_last_line or
                 d.cursor_position_row >= d.line_count - d.empty_line_count_at_the_end()
                 ):
@@ -131,11 +141,10 b' def newline_or_execute_outer(shell):'
             return
 
         if (status != 'incomplete') and b.accept_handler:
-            try_reformat()
+            reformat_text_before_cursor(b, d, shell)
             b.validate_and_handle()
         else:
             if shell.autoindent:
-                try_reformat()
                 b.insert_text('\n' + indent)
             else:
                 b.insert_text('\n')