SC2025 – ShellCheck Wiki

Make sure all escape sequences are enclosed in `\[..\]` to prevent line wrapping issues.

Problematic code:

PS1='\e[36m\$ \e(B\e[m'

Correct code:

PS1='\[\e[36m\]\$ \[\e(B\e[m\]'

Rationale:

Bash is unable to determine exactly which parts of your prompt are text and which are terminal codes. You have to help it by wrapping invisible control codes in \[..\] (and ensuring that visible characters are not wrapped in \[..\]).

Note: ShellCheck offers this as a helpful hint and not a robust check. Don't rely on ShellCheck to verify that your prompt is correct.

Exceptions

None.

BashFaq: I have a fancy prompt with colors, and now bash doesn't seem to know how wide my terminal is. Lines wrap around incorrectly.

ShellCheck is a static analysis tool for shell scripts. This page is part of its documentation.