Add ability to enable --show-all output when output is redirected

[dandavison]

Hi, I occasionally find myself wanting to capture the (very nice and useful) --show-all output. For example, in order to compute a diff on the --show-all output itself. Currently, the only way I know how to do this is to print the --show-all output to the screen, select it with a mouse, and copy it into a text file. I understand the reason bat must, by default, only enable -A if stdout is attached to an interactive terminal. If not by default then perhaps what I'm requesting could be something like

bat --show-all=always

Thanks for all the work on bat!

[dandavison]

I understand the reason bat must, by default, only enable -A if stdout is attached to an interactive terminal.

Hm, or maybe I don't :) GNU cat allows -A to change the input even when the output is redirected. So perhaps bat could do this by default also? Or even should?

~ gcat --version
cat (GNU coreutils) 8.30
Copyright (C) 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Torbjorn Granlund and Richard M. Stallman.
~ echo hello | gcat | bat -A   
───────┬─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
       │ STDIN
───────┼─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   1   │ hello␊
───────┴─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
~ echo hello | gcat -A | bat -A
───────┬─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
       │ STDIN
───────┼─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   1   │ hello$␊
───────┴─────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

[sharkdp]

Thank you for the feedback and for reporting this!

I would actually consider this a bug. bat -A … should print the replacement characters, even if we are piping the output to a file / another program.

What you can do for now is to use --decorations=always and/or --color=always. You can combine that with --plain if you don't want to see the grid etc.

[sharkdp]

Fixed in v0.16.0.

[arobase-che]

I didn't find a way to enable --show-all only if the output is interactive (stdout is a tty).

So here is a cat alias using bat:

function cat -d "Print a file nicely"
    if isatty stdout
        bat --show-all $argv
    else
        set -l catBin $(type --no-functions --path cat)
        $catBin $argv
    end
end

One can use bat -pp instead of cat:

function cat -d "Print a file nicely"
    if isatty stdout
        bat --show-all $argv
    else
        bat --style=plain --pager=never $argv
    end
end

Sorry for the noise.