Subject: Re: [PATCH] git-prompt: make colors available in custom prompts

From: Andreas Schwab <[email-masked]>
Date: Mon, 02 May 2016 09:15:55 +0200

Simon Oosthoek <[email-masked]> writes:

> Hi Andrew
>
> sorry, I only noticed your request this morning...
>
> On 22/04/16 07:00, Andrew Schwartzmeyer wrote:
>> diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
>> index f18aedc73..ffe79168c 100644
>> --- a/contrib/completion/git-prompt.sh
>> +++ b/contrib/completion/git-prompt.sh
>> @@ -12,8 +12,8 @@
>>   #        source ~/.git-prompt.sh
>>   #    3a) Change your PS1 to call __git_ps1 as
>>   #        command-substitution:
>> -#        Bash: PS1='[\u@\h \W$(__git_ps1 " (%s)")]\$ '
>> -#        ZSH:  setopt PROMPT_SUBST ; PS1='[%n@%m %c$(__git_ps1 " (%s)")]\$ '
>> +#        Bash: PS1="[\u@\h \W$(__git_ps1 ' (%s)')]\$ "
>> +#        ZSH:  setopt PROMPT_SUBST ; PS1="[%n@%m %c$(__git_ps1 ' (%s)')]\$ "
>
> I haven't tested this at all, but when using double quotes, you need to at
> least check all the escapings, like \$ should probably be: \\\$ when used
> in double quotes.

By using double quotes the command subsititution is expanded when PS1 is
set, which makes it pretty useless.

> The original reason for not using colors in command substitution mode was
> that the prompt string length was not calculated correctly by bash and it
> messed up the commandline with very long commands (relative to the
> terminal width), when browsing the command history.

If you want to include control characters in the prompt that don't
contribute to the length you have to enclose them in \[ \].  The problem
is that \[ \] are processed before embedded command substitutions are
expanded, thus they cannot produce such control characters.

Andreas.

-- 
Andreas Schwab, [email-masked]
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."