develop#python: use ptpython as default repl

profiles/develop/python/default.nix

@@ -17,15 +17,24 @@ in {
   environment.sessionVariables = {
     PYTHONSTARTUP = let
       startup = pkgs.writers.writePython3 "ptpython.py" {
-        libraries = [ python3Packages.ptpython ];
+        libraries = with python3Packages; [ ptpython ];
       } ''
+        from __future__ import unicode_literals
+
+        from pygments.token import Token
+
+        from ptpython.layout import CompletionVisualisation
+
         import sys
+
+        ${builtins.readFile ./ptconfig.py}
+
         try:
             from ptpython.repl import embed
         except ImportError:
             print("ptpython is not available: falling back to standard prompt")
         else:
-            sys.exit(embed(globals(), locals()))
+            sys.exit(embed(globals(), locals(), configure=configure))
       '';
     in "${startup}";
   };

profiles/develop/python/ptconfig.py

@@ -0,0 +1,164 @@
+__all__ = ("configure",)
+
+
+def configure(repl):
+    """
+    Configuration method. This is called during the start-up of ptpython.
+    :param repl: `PythonRepl` instance.
+    """
+    # Show function signature (bool).
+    repl.show_signature = True
+
+    # Show docstring (bool).
+    repl.show_docstring = True
+
+    # Show the "[Meta+Enter] Execute" message when pressing [Enter] only
+    # inserts a newline instead of executing the code.
+    repl.show_meta_enter_message = True
+
+    # Show completions. (NONE, POP_UP, MULTI_COLUMN or TOOLBAR)
+    repl.completion_visualisation = CompletionVisualisation.POP_UP
+
+    # When CompletionVisualisation.POP_UP has been chosen, use this
+    # scroll_offset in the completion menu.
+    repl.completion_menu_scroll_offset = 0
+
+    # Show line numbers (when the input contains multiple lines.)
+    repl.show_line_numbers = False
+
+    # Show status bar.
+    repl.show_status_bar = True
+
+    # When the sidebar is visible, also show the help text.
+    repl.show_sidebar_help = True
+
+    # Swap light/dark colors on or off
+    repl.swap_light_and_dark = False
+
+    # Highlight matching parethesis.
+    repl.highlight_matching_parenthesis = True
+
+    # Line wrapping. (Instead of horizontal scrolling.)
+    repl.wrap_lines = True
+
+    # Mouse support.
+    repl.enable_mouse_support = True
+
+    # Complete while typing. (Don't require tab before the
+    # completion menu is shown.)
+    repl.complete_while_typing = True
+
+    # Fuzzy and dictionary completion.
+    repl.enable_fuzzy_completion = False
+    repl.enable_dictionary_completion = False
+
+    # Vi mode.
+    repl.vi_mode = True
+
+    # Paste mode. (When True, don't insert whitespace after new line.)
+    repl.paste_mode = False
+
+    # Use the classic prompt. (Display '>>>' instead of 'In [1]'.)
+    repl.prompt_style = "classic"  # 'classic' or 'ipython'
+
+    # Don't insert a blank line after the output.
+    repl.insert_blank_line_after_output = True
+
+    # History Search.
+    # When True, going back in history will filter the history on the records
+    # starting with the current input. (Like readline.)
+    # Note: When enable, please disable the `complete_while_typing` option.
+    #       otherwise, when there is a completion available, the arrows will
+    #       browse through the available completions instead of the history.
+    repl.enable_history_search = False
+
+    # Enable auto suggestions. (Pressing right arrow will complete the input,
+    # based on the history.)
+    repl.enable_auto_suggest = False
+
+    # Enable open-in-editor. Pressing C-X C-E in emacs mode or 'v' in
+    # Vi navigation mode will open the input in the current editor.
+    repl.enable_open_in_editor = True
+
+    # Enable system prompt. Pressing meta-! will display the system prompt.
+    # Also enables Control-Z suspend.
+    repl.enable_system_bindings = True
+
+    # Ask for confirmation on exit.
+    repl.confirm_exit = True
+
+    # Enable input validation. (Don't try to execute when the input contains
+    # syntax errors.)
+    repl.enable_input_validation = True
+
+    # Use this colorscheme for the code.
+    repl.use_code_colorscheme("monokai")
+
+    # Set color depth (keep in mind that not all terminals support true color).
+
+    # repl.color_depth = 'DEPTH_1_BIT'  # Monochrome.
+    # repl.color_depth = 'DEPTH_4_BIT'  # ANSI colors only.
+    # repl.color_depth = "DEPTH_8_BIT"  # The default, 256 colors.
+    repl.color_depth = 'DEPTH_24_BIT'  # True color.
+
+    # Syntax.
+    repl.enable_syntax_highlighting = True
+
+    # Install custom colorscheme named 'my-colorscheme' and use it.
+    """
+    repl.install_ui_colorscheme('my-colorscheme', _custom_ui_colorscheme)
+    repl.use_ui_colorscheme('my-colorscheme')
+    """
+
+    # Add custom key binding for PDB.
+    """
+    @repl.add_key_binding(Keys.ControlB)
+    def _(event):
+        ' Pressing Control-B will insert "pdb.set_trace()" '
+        event.cli.current_buffer.insert_text('\nimport pdb; pdb.set_trace()\n')
+    """
+
+    # Typing ControlE twice should also execute the current command.
+    # (Alternative for Meta-Enter.)
+    """
+    @repl.add_key_binding(Keys.ControlE, Keys.ControlE)
+    def _(event):
+        event.current_buffer.validate_and_handle()
+    """
+
+    # Typing 'jj' in Vi Insert mode, should send escape. (Go back to navigation
+    # mode.)
+    """
+    @repl.add_key_binding('j', 'j', filter=ViInsertMode())
+    def _(event):
+        " Map 'jj' to Escape. "
+        event.cli.key_processor.feed(KeyPress(Keys.Escape))
+    """
+
+    # Custom key binding for some simple autocorrection while typing.
+    """
+    corrections = {
+        'impotr': 'import',
+        'pritn': 'print',
+    }
+    @repl.add_key_binding(' ')
+    def _(event):
+        ' When a space is pressed. Check & correct word before cursor. '
+        b = event.cli.current_buffer
+        w = b.document.get_word_before_cursor()
+        if w is not None:
+            if w in corrections:
+                b.delete_before_cursor(count=len(w))
+                b.insert_text(corrections[w])
+        b.insert_text(' ')
+    """
+
+
+# Custom colorscheme for the UI. See `ptpython/layout.py` and
+# `ptpython/style.py` for all possible tokens.
+_custom_ui_colorscheme = {
+    # Blue prompt.
+    Token.Layout.Prompt: "bg:#eeeeff #000000 bold",
+    # Make the status toolbar red.
+    Token.Toolbar.Status: "bg:#ff0000 #000000",
+}