Re: Prompt messed up if PS1 contains ANSI escape sequences

[Andreas Kähäri]

On Thu, Sep 07, 2023 at 04:03:39PM +0200, Gioele Barabucci wrote:
> On 07/09/23 15:50, Greg Wooledge wrote:
> > On Thu, Sep 07, 2023 at 03:46:23PM +0200, Gioele Barabucci wrote:
> > > On 07/09/23 15:00, alex xmb ratchev wrote:
> > > > u have to \[ esc-seq \]
> > > > eg inside \[ and \]
> > > > 
> > > > PS1=$'\u\[\e[1m\]\h\[\e[0m- '
> > > > 
> > > > should display hostname bold
> > > 
> > > Thanks for the suggestion, but adding \] does not really fix the problem, 
> > > it
> > > just masks it in many cases (better than nothing).
> > 
> > The \[ \] wrappings are required.  They're not "masking" the problem.
> > Your prompt is literally set incorrectly without them.
> 
> Agreed that \] is required. With "masking" I mean that the use of \]
> prevents the problem I'm referring to from showing up easily. But the
> problem is still there even when \] is used.
> 
> The following snippet shows that, even with the final \], Bash produces the
> same erroneous output and miscalculates the cursor position (it just needs a
> longer prompt):
> 
>     $ long_name="$(printf 'abcdef0123456789/%.0s' {0..20})"
>     $ mkdir -p /tmp/$long_name
>     $ cd /tmp/$long_name
>     $ PS1=$'\n\[\e[1m\]\w\[\e[m\] \$ '
> 
>     Now press the up arrow, then the down arrow)
> 
> Regards,
> 
> -- 
> Gioele Barabucci

I can't really reproduce the issue that you are seeing, but isn't the \n
(the newline) also a non-printable character that should be wrapped in
\[ \], since it has no width?

-- 
Andreas (Kusalananda) Kähäri
Uppsala, Sweden

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