fix: Replace mapfile to support Bash 3.2.57 pre-installed in macOS

[yermulnik]

Put an x into the box if that apply:

• This PR introduces breaking change.
• This PR fixes a bug.
• This PR adds new functionality.
• This PR enhances existing functionality.

Description of your changes

hooks/_common.sh: Replace mapfile to support Bash v3

[yermulnik]

Fixes: #626

[yermulnik]

Jeez, the PR-title workflow is challenging me 🤣

[MaxymVlasov]

Well it was replaced to mapfile from https://www.shellcheck.net/wiki/SC2207

Maybe we'd prefer a more readable variant than all this read IFS ololo done <<< | )?

  # shellcheck disable=SC2207 # Most readable variant
  local dir_paths_unique=( $(echo "${dir_paths[@]}" | tr ' ' '\n' | sort -u) )

[yermulnik]

Maybe we'd prefer a more readable variant than all this read IFS ololo done <<< | )?

The link that you refer to has this at the very top =)

[MaxymVlasov]

Yep, and I don't think that it is problematic, as paths must be split by spaces, just by tr ' ' '\n'

[MaxymVlasov]

We have no spaces in paths which can be split accidentally

[yermulnik]

1. The suggested ("problematic") code will split a path with spaces in it into different elements of array.
2. For the consistency sake I'd stay with while read approach. Else we need to replace other while read bits with the "other" solution.

[yermulnik]

You're confusing your inexperience of process substitution and array manipulation with "hard to understand".

That's a good shout out. But... but if between three of us one says "canonical" is less readable, while var=($(command)) is, then I reckon we have to provide readability and clarity for that one of us who prefers specific solution over other solution unless that preferred solution breaks for someone else (when we stumble upon someone with newlines in dir/file names 🤪).

[yermulnik]

unless that preferred solution breaks for someone else (when we stumble upon someone with newlines in dir/file names 🤪).

And even then we will just need to use a proper separator of \0, though this may require us to deal with diffs between BSD and GNU sort.

[MaxymVlasov]

And now code from #629

➜ docker run -ti bash:3.2.57  
bash-3.2# 
bash-3.2# eee() {
>   local -a dir_paths_unique
>   IFS=$'\n' dir_paths_unique=($(sort -u <<< "${dir_paths[*]}"))
>   unset IFS
>   printf '%s\n' "${dir_paths_unique[@]}"
> }
bash-3.2# 
bash-3.2# eee 11 44 11 "55 55"

bash-3.2# 
bash-3.2# 
bash-3.2# eee() {
>   local -a dir_paths_unique
>   IFS=$'\n' dir_paths_unique=($(sort -u <<< "${dir_paths[*]}"))
>   unset IFS
>   echo "${dir_paths_unique[@]}"
> }
bash-3.2# eee 11 44 11 "55 55"

I don't get it

[yermulnik]

Ah, I got it. This is about IFS and *.
Ok, #629 works.
Apologies for the confusion.

[robinbowes]

I suspect you're seeing differences because you're passing the params to a function, which means they're passing through an extra layer of quoting.

This code works for me on MacOS, with both v3 and v5:

set -euo pipefail

dir_paths=(
  11
  44
  11
  "55 55"
)

IFS=$'\n' dir_paths_unique=($(sort -u <<< "${dir_paths[*]}"))
printf '%s\n' "${dir_paths_unique[@]}"

$ /bin/bash --version
GNU bash, version 3.2.57(1)-release (x86_64-apple-darwin23)
Copyright (C) 2007 Free Software Foundation, Inc.

$ /bin/bash test.sh
11
44
55 55

$ bash --version
GNU bash, version 5.2.26(1)-release (x86_64-apple-darwin23.2.0)
Copyright (C) 2022 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

$ bash test.sh
11
44
55 55

[yermulnik]

@MaxymVlasov Please take another look at the change.

[yermulnik]

@MaxymVlasov Would you mind handling new release if needed as I need to drop off now.

[antonbabenko]

This PR is included in version 1.87.1 🎉