add emacs support (#932)

emacs support

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

apps/emacs/emacs.py

@@ -0,0 +1,341 @@
+import logging
+
+from talon import Context, Module, actions
+
+mod = Module()
+setting_meta = mod.setting(
+    "emacs_meta",
+    type=str,
+    default="esc",
+    desc="""What to use for the meta key in emacs. Defaults to 'esc', since that should work everywhere. Other options are 'alt' and 'cmd'.""",
+)
+
+mod.apps.emacs = "app.name: Emacs"
+mod.apps.emacs = "app.name: emacs"
+mod.apps.emacs = """
+os: mac
+app.bundle: org.gnu.Emacs
+"""
+
+ctx = Context()
+ctx.matches = "app: emacs"
+
+
+def meta(keys):
+    m = setting_meta.get()
+    if m == "alt":
+        return " ".join("alt-" + k for k in keys.split())
+    elif m == "cmd":
+        return " ".join("cmd-" + k for k in keys.split())
+    elif m != "esc":
+        logging.error(
+            f"Unrecognized 'emacs_meta' setting: {m!r}. Falling back to 'esc'."
+        )
+    return "esc " + keys
+
+
+def meta_fixup(k):
+    if k.startswith("meta-"):
+        k = meta(k[len("meta-") :])
+    elif "meta-" in k:
+        raise NotImplementedError("user.emacs_key(): please put meta- first")
+    return k
+
+
+@mod.action_class
+class Actions:
+    def emacs_meta(key: str):
+        "Presses some keys modified by Emacs' meta key."
+        actions.key(meta(key))
+
+    def emacs_key(keys: str):
+        """
+        Presses some keys, translating 'meta-' prefix to the appropriate keys. For
+        example, if the setting user.emacs_meta = 'esc', user.emacs_key("meta-ctrl-a")
+        becomes key("esc ctrl-a").
+        """
+        # TODO: handle corner-cases like key(" ") and key("ctrl- "), etc.
+        actions.key(" ".join(meta_fixup(k) for k in keys.split()))
+
+    def emacs_meta_x():
+        "Prompts user to enter a command name via execute-extended-command (M-x)."
+        actions.user.emacs_meta("x")
+
+    def emacs_prefix(n: int):
+        "Inputs a numeric prefix argument."
+        # Applying meta to each key can use fewer keypresses and 'works' in ansi-term
+        # mode.
+        actions.user.emacs_meta(" ".join(str(n)))
+        # # Alternative implementation using universal-argument (ctrl-u):
+        # actions.user.emacs("universal-argument")
+        # actions.key(" ".join(str(n)))
+
+    def emacs_help(key: str = None):
+        "Runs the emacs help command prefix, optionally followed by some keys."
+        # NB. f1 works in ansi-term mode; C-h doesn't.
+        actions.key("f1")
+        if key is not None:
+            actions.key(key)
+
+
+@ctx.action_class("user")
+class UserActions:
+    def cut_line():
+        actions.edit.line_start()
+        actions.user.emacs("kill-line", 1)
+
+    def split_window():
+        actions.user.emacs("split-window-below")
+
+    def split_window_vertically():
+        actions.user.emacs("split-window-below")
+
+    def split_window_up():
+        actions.user.emacs("split-window-below")
+
+    def split_window_down():
+        actions.user.emacs("split-window-below")
+        actions.user.emacs("other-window")
+
+    def split_window_horizontally():
+        actions.user.emacs("split-window-right")
+
+    def split_window_left():
+        actions.user.emacs("split-window-right")
+
+    def split_window_right():
+        actions.user.emacs("split-window-right")
+        actions.user.emacs("other-window")
+
+    def split_clear():
+        actions.user.emacs("delete-window")
+
+    def split_clear_all():
+        actions.user.emacs("delete-other-windows")
+
+    def split_reset():
+        actions.user.emacs("balance-windows")
+
+    def split_next():
+        actions.user.emacs("other-window")
+
+    def split_last():
+        actions.user.emacs("other-window", -1)
+
+    def split_flip():
+        # only works reliably if there are only two panes/windows.
+        actions.key("ctrl-x b enter ctrl-x o ctrl-x b enter")
+        actions.user.split_last()
+        actions.key("ctrl-x b enter ctrl-x o")
+
+    def select_range(line_start, line_end):
+        # Assumes transient mark mode.
+        actions.edit.jump_line(line_start)
+        actions.edit.jump_line(line_end + 1)
+        actions.user.emacs("exchange-point-and-mark")
+
+    # # Version that highlights without transient-mark-mode:
+    # def select_range(line_start, line_end):
+    #     actions.edit.jump_line(line_end + 1)
+    #     actions.key("ctrl-@ ctrl-@")
+    #     actions.edit.jump_line(line_start)
+
+    # dictation_peek() probably won't work in a terminal. PRs welcome.
+    def dictation_peek(left, right):
+        # clobber transient selection if it exists
+        actions.key("space backspace")
+        before, after = None, None
+        if left:
+            actions.edit.extend_word_left()
+            before = actions.edit.selected_text()
+            actions.user.emacs("pop-mark")
+        if right:
+            actions.edit.extend_line_end()
+            after = actions.edit.selected_text()
+            actions.user.emacs("pop-mark")
+        return (before, after)
+
+
+@ctx.action_class("edit")
+class EditActions:
+    def save():
+        actions.user.emacs("save-buffer")
+
+    def save_all():
+        actions.user.emacs("save-some-buffers")
+
+    def copy():
+        actions.user.emacs("kill-ring-save")
+
+    def cut():
+        actions.user.emacs("kill-region")
+
+    def undo():
+        actions.user.emacs("undo")
+
+    def paste():
+        actions.user.emacs("yank")
+
+    def delete():
+        actions.user.emacs("kill-region")
+
+    def file_start():
+        actions.user.emacs("beginning-of-buffer")
+
+    def file_end():
+        actions.user.emacs("end-of-buffer")
+
+    # works for eg 'select to top', but not if preceded by other selections :(
+    def extend_file_start():
+        actions.user.emacs("beginning-of-buffer")
+
+    def extend_file_end():
+        actions.user.emacs("end-of-buffer")
+
+    def select_none():
+        actions.user.emacs("keyboard-quit")
+
+    def select_all():
+        actions.user.emacs("mark-whole-buffer")
+        # If you don't use transient-mark-mode, maybe do this:
+        # actions.key('ctrl-u ctrl-x ctrl-x')
+
+    def word_left():
+        actions.user.emacs("backward-word")
+
+    def word_right():
+        actions.user.emacs("forward-word")
+
+    def extend_word_left():
+        actions.user.emacs_meta("shift-b")
+
+    def extend_word_right():
+        actions.user.emacs_meta("shift-f")
+
+    def sentence_start():
+        actions.user.emacs("backward-sentence")
+
+    def sentence_end():
+        actions.user.emacs("forward-sentence")
+
+    def extend_sentence_start():
+        actions.user.emacs_meta("shift-a")
+
+    def extend_sentence_end():
+        actions.user.emacs_meta("shift-e")
+
+    def paragraph_start():
+        actions.user.emacs("backward-paragraph")
+
+    def paragraph_end():
+        actions.user.emacs("forward-paragraph")
+
+    def line_start():
+        actions.user.emacs("move-beginning-of-line")
+
+    def line_end():
+        actions.user.emacs("move-end-of-line")
+
+    def extend_line_start():
+        actions.key("shift-ctrl-a")
+
+    def extend_line_end():
+        actions.key("shift-ctrl-e")
+
+    def line_swap_down():
+        actions.key("down ctrl-x ctrl-t up")
+
+    def line_swap_up():
+        actions.key("ctrl-x ctrl-t up:2")
+
+    def delete_line():
+        actions.key("ctrl-a ctrl-k")
+
+    def line_clone():
+        actions.user.emacs_key("ctrl-a meta-1 ctrl-k ctrl-y ctrl-y up meta-m")
+
+    def jump_line(n):
+        actions.user.emacs("goto-line", n)
+
+    def select_line(n: int = None):
+        if n is not None:
+            actions.edit.jump_line(n)
+        else:
+            actions.edit.line_start()
+        actions.edit.extend_line_end()
+        actions.edit.extend_right()
+        # This makes it so the cursor is on the same line, which can make
+        # subsequent commands more convenient.
+        actions.user.emacs("exchange-point-and-mark")
+
+    def indent_more():
+        actions.user.emacs("indent-rigidly", 4)
+
+    def indent_less():
+        actions.user.emacs("indent-rigidly", -4)
+
+    # These all perform text-scale-adjust, which examines the actual key pressed, so can't
+    # be done with actions.user.emacs.
+    def zoom_in():
+        actions.key("ctrl-x ctrl-+")
+
+    def zoom_out():
+        actions.key("ctrl-x ctrl--")
+
+    def zoom_reset():
+        actions.key("ctrl-x ctrl-0")
+
+    # Some modes override ctrl-s/r to do something other than isearch-forward, so we
+    # deliberately don't use actions.user.emacs.
+    def find(text: str = None):
+        actions.key("ctrl-s")
+        if text:
+            actions.insert(text)
+
+    def find_next():
+        actions.key("ctrl-s")
+
+    def find_previous():
+        actions.key("ctrl-r")
+
+
+@ctx.action_class("app")
+class AppActions:
+    def window_open():
+        actions.user.emacs("make-frame-command")
+
+    def tab_next():
+        actions.user.emacs("tab-next")
+
+    def tab_previous():
+        actions.user.emacs("tab-previous")
+
+    def tab_close():
+        actions.user.emacs("tab-close")
+
+    def tab_reopen():
+        actions.user.emacs("tab-undo")
+
+    def tab_open():
+        actions.user.emacs("tab-new")
+
+
+@ctx.action_class("code")
+class CodeActions:
+    def toggle_comment():
+        actions.user.emacs("comment-dwim")
+
+    def language():
+        # Assumes win.filename() gives buffer name.
+        if "*scratch*" == actions.win.filename():
+            return "elisp"
+        return actions.next()
+
+
+@ctx.action_class("win")
+class WinActions:
+    # This assumes the title is/contains the filename.
+    # To do this, put this in init.el:
+    # (setq-default frame-title-format '((:eval (buffer-name (window-buffer (minibuffer-selected-window))))))
+    def filename():
+        return actions.win.title()