Normalization of all bash scripts

[Pshepp]

We need to normalize all of our bash scripts. This includes:

• Normalization and inclusion of correct shabangs in each script
• Ensuring all file extensions are the same (so in files with a bash shabang, the file extension for these should be .bash). This can cause some messing with how the git history is tracked, so file extensions are not super high prority but we still need to hit this
• Correct usage of return and exit within our bash commands.
• Utilization of shellformat and shell check. The specific usage is below:
  • shellcheck --enable=require-variable-braces,quote-safe-variables,add-default-case <fileToLintHere>
  • shfmt -i 4 -ci -fn <fileToFormatHere>

Bug Description:
A recent bug caused by this was the gems/tests/run_tests.sh script having a #!/bin/sh shabang which caused it to not have the bash source command available to it. Furthermore, inconsistencies increases brain usage which is bad and makes scripts that would grab all specific files etc. to run tools on them more difficult.

Additional context
Think of different shells as kinda like different programming langauges. They are not all interchangeable, so we gotta keep that in mind. If we just stick to bash shells that use the baseline commands/progs we should be good. Getting a collection of all our scripts without shabangs would be good for someones first issue, actually changing them and ensuring the shabangs are correct is dependent on the devs skill level

Information regarding shabangs:

• https://stackoverflow.com/questions/16365130/what-is-the-difference-between-usr-bin-env-bash-and-usr-bin-bash
• https://stackoverflow.com/questions/21612980/why-is-usr-bin-env-bash-superior-to-bin-bash
• https://stackoverflow.com/questions/10376206/what-is-the-preferred-bash-shebang

Information Regarding exit vs. return

• Basically, exit exits the script while return returns a code. From my understanding, we should use return in our functions, and ngl we can use exit in our functions if the script is supposed to exit if a function fails but this pattern isnt very common. So let's just go for return on all our functions while using exit to react to a failed functions return value
• https://stackoverflow.com/questions/4419952/difference-between-return-and-exit-in-bash-functions
• https://tldp.org/LDP/abs/html/exit-status.html
• https://www.baeldung.com/linux/return-vs-exit

[gitoliver]

What should everything be
#!/bin/bash?
#!/usr/bin/env bash?

[Pshepp]

as with most code bits, it depends lolol. These SO posts have a good starting point to understanding, and not just the top comments have decent info:

• https://stackoverflow.com/questions/16365130/what-is-the-difference-between-usr-bin-env-bash-and-usr-bin-bash
• https://stackoverflow.com/questions/21612980/why-is-usr-bin-env-bash-superior-to-bin-bash
• https://stackoverflow.com/questions/10376206/what-is-the-preferred-bash-shebang

I would say just using the following would be fine. Now, as one of the dudes in the 2nd link said on different linoox systems it wont work depending on how people have stuff installed but meh.......

#!/bin/bash

We can also use the following, but it is less secure iirc but idk how much of this being less secure is bs.....

#!usr/bin/env bash

@thecoulter plz weigh in