`install.sh` does not add GETMESH_HOME to the path about getmesh

[toffentoffen]

I think I've found the reason why it is failing, and it's failing on macOSX BigSur bash (GNU bash, version 3.2.57(1)-release (arm64-apple-darwin20)). MacOsX Bigsur is shipped with a really old version.
It seems that enabling errexit

getmesh/site/install.sh

Line 16 in fd6d94a

set -e

is making the script exit when if ! command grep -qc 'GETMESH_HOME' "$detected_profile"; then is executed . Even though it is a tested command (inside an if). A tested command, as per gnu bash documentation, is:

The shell does not exit if the command that fails is part of the command list immediately following a while or until keyword, part of the test in an if statement, part of any command executed in a && or || list except the command following the final && or ||

Extensive information about set -e can be found at http://mywiki.wooledge.org/BashFAQ/105
which includes as well a reference to how subshells have propagated that flag https://www.in-ulm.de/~mascheck/various/set-e/

Possible Solutions

• Use set +e before the problematic if statement: I would discard that option because we will need to remember to set it back, and if the code branching changes over time it can be difficult to maintain it.

• Subshells. Seems like subshell does the trick because set -e is not propagated (maybe even by mistake). We can either:

  • extracting out the grep command and storing the count into a local variable:

    local getmesh_home_count=$(command grep -c 'GETMESH_HOME' "$detected_profile")
    if [[ "$getmesh_home_count" -eq 0 ]];
  

  • wrap the if command in parenthesis: if ! (command grep -qc 'GETMESH_HOME' "$detected_profile"); then

• Remove set -e from the script as it seems problematic. I would suggest avoid that approach as it will make us to implement error handling manually at each command. Although it might be the best, I don't think it is worth the effort as this problem might only happen in concrete bash versions.

I will go ahead and create a PR for using the wrap if statement approach.

[mathetake]

thanks so much @toffentoffen for the thorough investigation!

I will go ahead and create a PR for using the wrap if statement approach.

agreed, thank you! 😄