Handle mode condition in inputrc

[ima1zumi]

Close: #624

I've implemented .inputrc to properly handle the mode, which can be set to either emacs or vi. For vi, set to vi_insert mode.
Upon checking Readline's behavior, it appears that else is entered when the mode check fails.
For instance, if $if mode=vi is written, else will not be executed.

ref: https://tiswww.case.edu/php/chet/readline/readline.html#Conditional-Init-Constructs

[tompng]

condition should be true only when editing_mode_label matches arg.

"\e\C-j": vi-editing-mode
"\C-e": emacs-editing-mode

set editing-mode vi
set keymap emacs
$if mode=emacs
  # skipped because editing-mode(==vi) is not emacs
  "x": "A"
$else
  # executed. set emacs-keymap "x" to "B" (insert "B")
  "x": "B"
$endif
# type ESC C-e to switch to emacs mode, type x, then B is inserted

"\e\C-j": vi-editing-mode
"\C-e": emacs-editing-mode

set editing-mode emacs
set keymap vi
$if mode=vi
  # skipped because editing-mode(==emacs) is not vi
  "x": "A"
$else
  # executed. set vi-keymap "x" to "iB" (switch to insert mode and insert "B")
  "x": "iB"
$endif
# type ESC C-j to switch to vi-insert, type ESC to switch to vi-command, type x, then B is inserted

And looks like key is registered to keymap (== @keymap_label), so I think we don't need to introduce @editing_mode_section.

[ima1zumi]

Indeed, you're right. I've fixed it!

[tompng]

I think this test case is wrong.

With this inputrc file saved to ./inputrc

$if mode=vi
  "x": "X"
$else
  "y": "Y"
$endif

Only "y"→"Y", the $else part is reflected.

$ echo x | INPUTRC=./inputrc ruby -rreadline -e "p Readline::VERSION; Readline.readline'>'"
"8.2"
>x
$ echo y | INPUTRC=./inputrc ruby -rreadline -e "p Readline::VERSION; Readline.readline'>'"
"8.2"
>Y

[ima1zumi]

Thanks for letting me know! I've fixed it and added tests.

[tompng]

I think if mode=xxx does not modify keymap_label.

I tried this inputrc

set editing-mode vi
set keymap emacs
$if mode=vi
  "x": "FOOBAR"
$endif

With this command. Typing x in vi mode just inserts x. After switching to emacs mode with \e\C-e, typing x inserts FOOBAR.

$ ruby -e 'puts "vi:x, \e\C-e\C-eemacs:x"' | ruby -rreadline -e "puts Readline::VERSION;Readline.readline('>')"
8.2
>vi:x, emacs:FOOBAR

I think Readline reads inputrc like this

# Sets mode_label and keymap_label to vi
set editing-mode vi
# Change keymap_label to emacs. mode_label is still vi.
set keymap emacs
# condition=true because current mode_label is vi
$if mode=vi
  # sets keybinding to current keymap_label=emacs
  "x": "FOOBAR"
$endif

[ima1zumi]

Thanks for letting me know. I fixed. If you see anything else wrong, please let me know 🙏

[tompng]

LGTM 👍