Strip color codes from ascii art line length calculations

[Syphist]

Description

This removes color and formatting codes from the line length calculation to allow for more control over custom ascii art. This would also fix issues I found when attempting to use the patch in #1220.

Features

Allows for support for finer control of ascii art using escapes such as "[38;5;39m" for defining coloring and formatting in the terminal.

Issues

None that I have found

TODO

Nothing

Fixed Issues

This so far only works if you directly paste the character for \033 or "" into the file. I was unable to get it to work for both.

[Syphist]

I have made several more attempts to work around SC2001, but have had no success. I am wondering if it is too complex to do it with the search and replace in bash and may need to be done with sed. I will probably make further attempts at this, if anyone else has any ideas feel free to let me know too.

[Syphist]

I have figured out the solution and have updated my code accordingly and have cleaned it up. I have tested both with the pasted character in the ascii file and the escape code and both work. This is also much faster than my initial sed implementation. I have updated the OP to reflect these changes as well as clarify a few things.

[Z-8Bit]

+1 I agree, it's much needed this.

[thenick775]

+1 this modification works well for me, have tested on Big Sur

[fvegaswp]

Just tested this with colored ascii generated with lolcat and works great.

[jonaramos]

Tested with colored ascii generated from jp2a and ascii-image-converter. Thanks Syphist.

[hykilpikonna]

Lol I actually ran into this issue while creating HyFetch. My solution was to pass in a separate ascii_len variable:

Thanks a lot!

[hykilpikonna]

Works!

[hykilpikonna]

Thank you for your contribution!

This PR is merged into hyfetch since this repo (dylanaraps/neofetch) seems no longer maintained.

HyFetch is a fork of neofetch with LGBTQ pride flags, but the repo also maintains an updated version of the original neofetch, addressing many pull requests that are not merged in the original repo.

Read the "Running Updated Original Neofetch" section for more info!

[hykilpikonna]

I found a bug in the last line of strip_escape_codes:

-     eval "$2=\"${output}\""
+     eval "$2='${output}'"

If there exists $ signs in the ascii art, this eval statement will replace the $ with a variable content. You should use single quotes to prevent this.

Before Fix:

After Fix:

[Syphist]

I have committed your fix. Thanks for finding a solution and testing further.

[hykilpikonna]

Okay I found another bug lol

- while IFS=$'\n' read -r line; do
+ while IFS=$'\n' read line; do

The width is incorrectly calculated for ascii distros with backslashes in them (e.g. Bedrock) because the backslashes were not treated as escape characters in read -r while they are actually escaped when defining the ASCII:

So, if read -r is used, the escaped backslash (\\) will not be resolved as one character but two characters, making the ascii length longer. (https://github.com/hykilpikonna/hyfetch/issues/19)

Before Fix:

After Fix:

[Syphist]

Thanks @hykilpikonna I fixed the issue on my fork as well just in case this ever gets merged upstream to neofetch or if someone bothers to use my fork.