F39 Change Proposal: Color Bash Prompt (System Wide)

[Aoife Moloney]

https://fedoraproject.org/wiki/Changes/Color_Bash_Prompt

== Summary ==
Introduce a default colored prompt for Fedora's default shell bash.

== Owner ==

* Name: [[User:Petersen| Jens Petersen]]

* Email:

== Detailed Description ==
For a long time the Fedora default shell prompt has been monochrome,
which makes it difficult to find shell prompt commands between long
command outputs when scrolling through terminal shell output.
This Change introduces a simple default colored shell prompt, which
users can also easily theme themselves.

[https://petersen.fedorapeople.org/color-bash-prompt.png screenshot of
color bash prompt in gnome-terminal]

== Feedback ==
Initial [https://lists.fedoraproject.org/archives/list/[e-mail]/...
devel list discussion thread]

There seems to be a general desire to have a colored prompt like other
popular distros, which commonly use green etc, though some concerns
were raised about colorblind users. However given that the original
prompt was black & white, and the new one while colored will still be
essentially monochromatic, it should be less of a problem and users
will easily be able to turn off or change any color introduced.

== Benefit to Fedora ==
Fedora will have a more modern and distinct default shell prompt.

== Scope ==
* Proposal owners:
** update the default bash PS1 to a simple essentially monochromatic
prompt (restricted to interactive color terminals).
** like the old default prompt, no external commands or processes will
be run by PS1 by default

* Other developers: bash and/or setup package maintainers to be
consulted on the preferred implementation file location

* Release engineering: [https://pagure.io/releng/issues #Releng issue number]

* Policies and guidelines: N/A (not needed for this Change)

* Trademark approval: N/A (not needed for this Change)

* Alignment with Community Initiatives:

== Upgrade/compatibility impact ==
No impact for rpm editions, ostree editions may gain the default color
prompt if they include its package.

== How To Test ==
* install Fedora and test the new PS1 prompt in various terminals and scenarios
** desktop default terminals should be expected to render the new prompt well
* try customizing the prompt theme by setting for example
`PROMPT_COLOR='1;33'` (bright/bold yellow), etc

A proof of concept can be tested today with
https://copr.fedorainfracloud.org/coprs/petersen/bash-color-prompt/
([https://copr-dist-git.fedorainfracloud.org/cgit/petersen/bash-color-prompt/b...
source git repo])

== User Experience ==
Fedora users will now benefit from a clear self-colored shell prompt,
which should make the separation between command outputs and shell
prompts much clearer and they can also easily change the prompt
coloring in real-time as they desire.

== Dependencies ==
None

== Contingency Plan ==

* Contingency mechanism: Change owner will revert PS1 back to monochrome prompt
* Contingency deadline: Beta freeze
* Blocks release? Yes

== Documentation ==
[https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_(Select_Graphic_Rendition...
ANSI color attributes] (Wikipedia)

== Release Notes ==
The default shell prompt is now in a distinct color for increased
clarity and the theme can be customized.

[Vít Ondruch]

Dne 05. 07. 23 v 11:25 Aoife Moloney napsal(a):
> https://fedoraproject.org/wiki/Changes/Color_Bash_Prompt
>
> == Summary ==
> Introduce a default colored prompt for Fedora's default shell bash.
>
> == Owner ==
>
> Name: [[User:Petersen| Jens Petersen]]
>
> Email:
>
> == Detailed Description ==
> For a long time the Fedora default shell prompt has been monochrome,
> which makes it difficult to find shell prompt commands between long
> command outputs when scrolling through terminal shell output.
> This Change introduces a simple default colored shell prompt, which
> users can also easily theme themselves.
>
> [https://petersen.fedorapeople.org/color-bash-prompt.png screenshot of
> color bash prompt in gnome-terminal]
>
> == Feedback ==
> Initial [https://lists.fedoraproject.org/archives/list/[e-mail]/...
> devel list discussion thread]
>
> There seems to be a general desire to have a colored prompt like other
> popular distros, which commonly use green

Shouldn't blue be the default for Fedora?

And I think that dark as well as light color schemes should be 
considered. IOW I appreciate the screenshot attached above, but could 
you also attach one with the light scheme? Thx a lot.

Vít
> etc, though some concerns
> were raised about colorblind users. However given that the original
> prompt was black & white, and the new one while colored will still be
> essentially monochromatic, it should be less of a problem and users
> will easily be able to turn off or change any color introduced.
>
> == Benefit to Fedora ==
> Fedora will have a more modern and distinct default shell prompt.
>
> == Scope ==
> Proposal owners:
>
> ** update the default bash PS1 to a simple essentially monochromatic
> prompt (restricted to interactive color terminals).
> ** like the old default prompt, no external commands or processes will
> be run by PS1 by default
> Other developers: bash and/or setup package maintainers to be
>
> consulted on the preferred implementation file location
>
> Release engineering: [https://pagure.io/releng/issues #Releng issue number]
>
> Policies and guidelines: N/A (not needed for this Change)
>
> Trademark approval: N/A (not needed for this Change)
>
> Alignment with Community Initiatives:
>
> == Upgrade/compatibility impact ==
> No impact for rpm editions, ostree editions may gain the default color
> prompt if they include its package.
>
> == How To Test ==
> install Fedora and test the new PS1 prompt in various terminals and scenarios
>
> ** desktop default terminals should be expected to render the new prompt well
> try customizing the prompt theme by setting for example
>
> `PROMPT_COLOR='1;33'` (bright/bold yellow), etc
>
> A proof of concept can be tested today with
> https://copr.fedorainfracloud.org/coprs/petersen/bash-color-prompt/
> ([https://copr-dist-git.fedorainfracloud.org/cgit/petersen/bash-color-prompt/b...
> source git repo])
>
> == User Experience ==
> Fedora users will now benefit from a clear self-colored shell prompt,
> which should make the separation between command outputs and shell
> prompts much clearer and they can also easily change the prompt
> coloring in real-time as they desire.
>
> == Dependencies ==
> None
>
> == Contingency Plan ==
> Contingency mechanism: Change owner will revert PS1 back to monochrome prompt
> Contingency deadline: Beta freeze
> Blocks release? Yes
>
> == Documentation ==
> [https://en.wikipedia.org/wiki/ANSI_escape_code#SGR_(Select_Graphic_Rendition...
> ANSI color attributes] (Wikipedia)
>
> == Release Notes ==
> The default shell prompt is now in a distinct color for increased
> clarity and the theme can be customized.

[Tomasz Torcz]

On Fri, Jul 07, 2023 at 01:38:08PM +0200, Vít Ondruch wrote:
> > There seems to be a general desire to have a colored prompt like other
> > popular distros, which commonly use green
>
> Shouldn't blue be the default for Fedora?
>
> And I think that dark as well as light color schemes should be considered.

I thought we should be using ANSI_COLOR from /etc/os-release. Which is
blue on Fedora.

[Chris Adams]

Once upon a time, Vít Ondruch  said:
> Shouldn't blue be the default for Fedora?

Blue is probably a bad idea in a prompt, as the human eye doesn't
perceive blue as strongly as green.  The prompt isn't about art/style,
it's purely about functionality.

[David Both]

I agree that blue is not good. It was impossible to read the welcome
messages during boot and startup. The cyan/teal is much better.

I typically use amber on black but sometimes use green on black so I'm
not sure that green would help those who also use green font color. For
me, on a black background, #54FFFF works really well for both. Not so
well on light backgrounds though.

[Marián Konček]

I actually copy-paste the Debian prompt since Debian Jessie on my systems.
Even though it uses blue-green colors, I can see it very well on both 
white and black background.

I think it would be nicer if we played around with several options and 
have the user have a simple way of choosing. There are many variants, 
some using git info, some using exit codes and so...

On 7. 7. 2023 14:56, Chris Adams wrote:
> Once upon a time, Vít Ondruch  said:
> > Shouldn't blue be the default for Fedora?
>
> Blue is probably a bad idea in a prompt, as the human eye doesn't
> perceive blue as strongly as green.  The prompt isn't about art/style,
> it's purely about functionality.

[Jens-Ulrik Petersen]

On Fri, Jul 7, 2023 at 9:36 PM Marián Konček  wrote:
> I actually copy-paste the Debian prompt since Debian Jessie on my systems.
> Even though it uses blue-green colors, I can see it very well on both
> white and black background.

Okay
> I think it would be nicer if we played around with several options and
> have the user have a simple way of choosing.

They *can* set PROMPT_COLOR to change coloring immediately.
But it would be nice to have a configuration tool/UI some day.
> There are many variants, some using git info, some using exit codes and
> so...

Exit code is already handled in the current implementation.
I would like to make it more extensible in the future...

But I made a criteria that this simple MVP should not use PROMPT_COMMAND
nor should the default PS1 cause *any* external process to run by default.
So anyway this Change is not setting the bar very high, by design:
there are certainly lots of more powerful solutions around
like powerline or starship etc, and this Change is not competing with them.
:-)
The hope is that a simple conservative solution like this would be broadly
acceptable as a desktop default.

Thanks, Jens

[Jens-Ulrik Petersen]

On Fri, Jul 7, 2023 at 7:38 PM Vít Ondruch  wrote:
> Dne 05. 07. 23 v 11:25 Aoife Moloney napsal(a):
> > https://fedoraproject.org/wiki/Changes/Color_Bash_Prompt
>
> :
>
> There seems to be a general desire to have a colored prompt like other
> > popular distros, which commonly use green
> Shouldn't blue be the default for Fedora?

(In some palettes the visibility of cyan text on white background is really
poor
and similarly blue text is often hard to make out on black background.)

We could try PROMPT_COLOR='46' which would give us a prompt with cyan
background.
Background prompt color actually achieves better contrast and stands out
more I feel:

https://petersen.fedorapeople.org/color-bash-prompt-cyan-dark.png
https://petersen.fedorapeople.org/color-bash-prompt-cyan-light.png

It has the advantage of not looking like colored text output by some
commands:
e.g. dnf may print packages in green. I personally use a prompt background
color
for good contrast.

And I think that dark as well as light color schemes should be
> considered. IOW I appreciate the screenshot attached above, but could
> you also attach one with the light scheme? Thx a lot.

Okay, I have added a link to a light gnome-terminal screenshot too on the
page.
https://petersen.fedorapeople.org/color-bash-prompt-light.png

Jens

[Patrick Creech]

Sorry if this comes through twice.  Apparently thunderbird's "Reply to 
list" thought I meant to send it to devel-announce, not devel.

On 7/5/23 05:25, Aoife Moloney wrote:
> == Feedback ==
> Initial 
> [https://lists.fedoraproject.org/archives/list/[e-mail]/...
>
> devel list discussion thread]
>
> There seems to be a general desire to have a colored prompt like other
> popular distros, which commonly use green etc, though some concerns
> were raised about colorblind users. However given that the original
> prompt was black & white, and the new one while colored will still be
> essentially monochromatic, it should be less of a problem and users
> will easily be able to turn off or change any color introduced.

So, a personal anecdote, but to provide some food for thought in favor 
if this:

I know it's ridiculous, but early in my playing with linux history, I 
was very turned off by Fedora for _precisely_ the fact that the prompt 
color default wasn't something more along the lines of what other 
distros did at the time.  (These were back in the late single 
digit/early teens Fedora days).  Any time I tried to stick with Fedora, 
this was always something that eventually made me want to switch back to 
something else.

Nowadays I powerline and move on, but some food for thought.  It just 
didn't make Fedora feel "cool" or "modern".  No matter how silly that 
thought actually was.

[Jens-Ulrik Petersen]

Thanks for the replies so far.

Unfortunately there is no easy way to detect dark or light terminals, to my
knowledge at least.
Green seems the most friendly color across different palettes and terminals.
Though these days modern terminals tend to default to dark
(most Fedora editions' default terminals are dark by default I think).

https://copr-dist-git.fedorainfracloud.org/cgit/petersen/bash-color-prompt/b...
lists various examples of how users can customize the color: eg
PROMPT_COLOR='33' (for yellow/brown).

[Per Bothner]

On 7/9/23 22:20, Jens-Ulrik Petersen wrote:
> Unfortunately there is no easy way to detect dark or light terminals, to my knowledge at least.

You can use the xterm OSC 11;? sequence to request the text background color.
Emacs uses this to select light or dark theming.

[Eric Curtin]

If you are looking for other ideas, I embed loads of useful info in my prompt:

https://imgur.com/a/kVCyVPK

time, so you can roughly measure the time between commands, CPU architecture, how far ahead or behind you are in a git repo.

But this gets a +1 from me regardless of the result, colors are good if the terminal supports it.

[Eduard Lucena]

What I did with the i3 Spin was to ask to the Design team for something
that fits Fedora's color palette. I think for this you could do the same.

Br,

[Dan Čermák]

Hi,

Aoife Moloney  writes:
> https://fedoraproject.org/wiki/Changes/Color_Bash_Prompt
>
> == Summary ==
> Introduce a default colored prompt for Fedora's default shell bash.
>
> == Owner ==
>
> Name: [[User:Petersen| Jens Petersen]]
>
> Email:
>
> == Detailed Description ==
> For a long time the Fedora default shell prompt has been monochrome,
> which makes it difficult to find shell prompt commands between long
> command outputs when scrolling through terminal shell output.
> This Change introduces a simple default colored shell prompt, which
> users can also easily theme themselves.
>
> [https://petersen.fedorapeople.org/color-bash-prompt.png screenshot of
> color bash prompt in gnome-terminal]

I am overall in favor of this change, thanks for working on this Jens
and for keeping it simple!

I like the simple look, but I would suggest to add a either spaces
in front and after the exit code or braces around it or something else
visually distinctive from the rest of the prompt. At the moment the exit
code looks like something that got crammed into the prompt by accident.

Cheers,

Dan

[Matthew Miller]

On Sat, Jul 15, 2023 at 05:22:15PM +0200, Dan Čermák wrote:
> > For a long time the Fedora default shell prompt has been monochrome,
> > which makes it difficult to find shell prompt commands between long
> > command outputs when scrolling through terminal shell output.
> > This Change introduces a simple default colored shell prompt, which
> > users can also easily theme themselves.
> >
> > [https://petersen.fedorapeople.org/color-bash-prompt.png screenshot of
> > color bash prompt in gnome-terminal]
>
> I am overall in favor of this change, thanks for working on this Jens
> and for keeping it simple!

Me too!

[Neal Gompa]

On Sat, Jul 15, 2023 at 3:04 PM Matthew Miller  wrote:
> On Sat, Jul 15, 2023 at 05:22:15PM +0200, Dan Čermák wrote:
> > > For a long time the Fedora default shell prompt has been monochrome,
> > > which makes it difficult to find shell prompt commands between long
> > > command outputs when scrolling through terminal shell output.
> > > This Change introduces a simple default colored shell prompt, which
> > > users can also easily theme themselves.
> > >
> > > [https://petersen.fedorapeople.org/color-bash-prompt.png screenshot of
> > > color bash prompt in gnome-terminal]
> >
> > I am overall in favor of this change, thanks for working on this Jens
> > and for keeping it simple!
>
> Me too!

I have a couple of suggestions:

* username and hostname be slightly different colors
* wrap the return code in brackets

This is what I have for my fish prompt, as an example:
https://ngompa.fedorapeople.org/color-fish-prompt.png

[Peter Boy]

> Am 15.07.2023 um 21:03 schrieb Matthew Miller :
>
> On Sat, Jul 15, 2023 at 05:22:15PM +0200, Dan Čermák wrote:
> > > For a long time the Fedora default shell prompt has been monochrome,
> > > which makes it difficult to find shell prompt commands between long
> > > command outputs when scrolling through terminal shell output.
> > > This Change introduces a simple default colored shell prompt, which
> > > users can also easily theme themselves.
> > >
> > > [https://petersen.fedorapeople.org/color-bash-prompt.png screenshot of
> > > color bash prompt in gnome-terminal]
> >
> > I am overall in favor of this change, thanks for working on this Jens
> > and for keeping it simple!
>
> Me too!

And me too. :-)

And it would be nice to get some color issues fixed in one step, e.g. light yellow warning and error messages a white background. Really ‚fun' for your eyesight

--
Peter Boy
https://fedoraproject.org/wiki/User:Pboy
[e-mail]

Timezone: CET (UTC+1) / CEST /UTC+2)

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