Powerline PS1 line wrapping

Question

Context

GNU bash 4.4.12(1)-release
Powerline 2.5.2-1

Powerline installed from arch linux packages, not from pip.

PS1 Script

update-ps() {
    export PS1="$(powerline shell aboveleft)"
    export PS2="$(powerline shell left)"
}

export PROMPT_COMMAND="update-ps;$PROMPT_COMMAND"

Powerline config

Problem

I have the same problem as him, when I write a few chars the line wraps and I start writing in the same line, overwriting what I already wrote (including ps1).

I am aware that this could be a non-printable character problem, but doesn't it means that it's a powerline bug? What other problems can it be?

As an aside -- allowing dashes in function names isn't guaranteed by POSIX sh, nor portable to all historical bash versions; you might want to use an underscore instead. — Charles Duffy, Apr 07 '17 at 00:55
More on the point -- could you provide the output of `declare -p PS1` and `declare -p PS2`? — Charles Duffy, Apr 07 '17 at 00:56
(As an aside -- unless you're also going to export the `prompt-command` function with `export -f`, and don't need any non-bash shells to work in your environment, you should probably keep the values of `PS1`, `PS2` and `PROMPT_COMMAND` shell-local rather than exporting them). — Charles Duffy, Apr 07 '17 at 00:58
Hmm. `printf '%q=%q\n' PS1 "$PS1" PS2 "$PS2"` might be a little easier to follow. — Charles Duffy, Apr 07 '17 at 01:07
PS1=$'\E[0;38;5;240;48;5;4;1m seiji \E[0;38;5;4;48;5;1;22m \E[0;38;5;251;48;5;1m master \E[0;38;5;1;48;5;236;22m \E[0;38;5;7;48;5;236;1m~ \E[0;38;5;236;49;22m \E[0m\n\E[0;38;5;240;48;5;4;1m $ \E[0;38;5;4;49;22m \E[0m' — Seiji Hirao, Apr 07 '17 at 01:09
PS2=$'\E[0;38;5;240;48;5;4;1m $ \E[0;38;5;4;49;22m \E[0m' — Seiji Hirao, Apr 07 '17 at 01:09
Could you add output from `locale` and `python -c 'import locale; print locale.getdefaultlocale()'` as well? — Charles Duffy, Apr 07 '17 at 01:11
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/140132/discussion-between-seiji-hirao-and-charles-duffy). — Seiji Hirao, Apr 07 '17 at 01:13

score 1 · Answer 1 · answered Oct 22 '19 at 07:02

1

For me changing in ~.bashrc: from:

. /usr/local/lib/python2.7/dist-packages/powerline/bindings/shell/powerline.sh

to

. /usr/local/lib/python2.7/dist-packages/powerline/bindings/bash/powerline.sh

resolved the issue

answered Oct 22 '19 at 07:02

Michal Lis

491
5
4

score 0 · Answer 2 · answered Apr 19 '19 at 18:12

This can occur when the locale is incorrect, or when glibc is built with "C" locale, which does not support unicode characters. Powerline uses non-breaking spaces (2-byte) and also uses 2-byte unicode characters for the triangles. For each one of these characters, the shell (not powerline) thinks that 1 extra character has been printed. If you have 5 spaces and 3 triangles in the prompt, then the prompt will wrap 8 characters before it hits the end of the line. From there everything behaves incorrectly. This only relates to Powerline in the sense that Powerline uses unicode characters in the prompt.

The fix is to correct the locale so the shell understands 2-byte unicode. You can run "locale" to see if the shell is using "C", in which case it needs to be fixed. For my application, we were running Powerline in a Docker image running Centos Linux. We had to fix the locale in /etc/yum.conf to use the lowercase form of utf8 like so:

sed -i 's/UTF-8/utf8/' /etc/yum.conf

Then rebuild glibc-common with the fix:

yum reinstall glibc-common

After that, new terminals behaved and the prompt wrapped correctly. We then modified our Docker image to fix yum.conf before installing glibc. However, we found one of our modules was changing the locale back to C (LANG="C"), so we used the LC_ALL env var to override it:

LC_ALL=en_US.UTF_8

After that, all new terminals behaved correctly.

Powerline PS1 line wrapping

Context

PS1 Script

Powerline config

Problem

2 Answers2