[Feature] Make Amber work in Git Bash on Windows

[hdwalters]

Is your feature request related to a problem? Please describe.
Amber is officially supported on Linux and Mac systems only. I use Windows in my day job; the Amber website advises me to install WSL, but I use Git Bash as my primary shell.

Describe the solution you'd like
I would like to be able to use Amber in Git Bash on Windows.

Describe alternatives you've considered
The alternative is to install WSL, but that is not an option for me.

Additional context
The Amber source code has only one Windows conditional compilation directive. Nothing I've seen looks like it would break on Windows; and I already fixed the place I found where a file system path was being constructed by hand, rather than using PathBuf::join(). I do not see any major reasons why it should not work on Windows.

[b1ek]

what if you compile it on your windows machine, and then run an amber program on that machine with git bash? if its good, then its just a matter of building the releases for windows

[hdwalters]

Yep, I intend to try that when I get a chance to set up a GitHub SSH key on that PC. This issue is a placeholder for discussion of any further work that may be necessary.

[Mte90]

Maybe also setup something on the CI it will be useful

[Ph0enixKM]

Yeah... I just wanted to avoid all the "the amber compiler compiles to .bat files that don't work" kind of drama. The compiler should work perfectly fine on Windows. We can add windows in CI pretty easily

[hdwalters]

Compile to ".bat" files? Shudder. Neither do we want PowerShell.

[hdwalters]

I tried compiling and running Amber on Git Bash:

$ cat hello.ab
#!/usr/bin/env amber
echo "Hello world"

$ amber.exe hello.ab -
#!/usr/bin/env bash
# Written in [Amber](https://amber-lang.com/)
# version: 0.3.5-alpha
# date: 2024-09-25 18:13:00
# #!/usr/bin/env amber
echo "Hello world"

$ ./hello.ab
Error: Os { code: 3, kind: NotFound, message: "The system cannot find the path specified." }

So it looks like the compiler works fine (as expected) but it's unable to find some resource in the file system when it tries to execute the transpiled code. I'll have a go at fixing this; shouldn't be too hard.

[hdwalters]

That NotFound error was because the Amber compiler tries to run /usr/bin/env bash -c "[code]", and that doesn't work in Git Bash. I wrote some alternate code for Windows builds, which searches the directories in the PATH enviroment variable for bash.exe, and calls that. Typically it will find C:\Program Files\Git\usr\bin\bash.exe.

$ cat hello.ab
#!/usr/bin/env amber
echo "Hello world"

$ amber.exe hello.ab -
#!/usr/bin/env bash
# Written in [Amber](https://amber-lang.com/)
# version: 0.3.5-alpha
# date: 2024-09-26 22:38:51
# #!/usr/bin/env amber
echo "Hello world"

$ ./hello.ab
Hello world

PR forthcoming, once I've done a final test on my Windows machine.

[hdwalters]

However, note that the unit tests do not run, at least in part because bc is not installed by default on Git Bash. There are instructions on how to install it, and I can try to work through them... but honestly, how bothered do we need to be about this?

[Mte90]

#366

The plan is to remove bc and sed requirements, I have a PR pending for Sed and should remove the bc requirement.
The PR is blocked by an escaping issue in the code generated #381

[hdwalters]

Ok. I can either hold off for now, or submit a PR on the understanding that unit tests will not work without further work. Preferences anyone?

[hdwalters]

I'm inclined to submit the PR anyway. It's not like it will hurt anything.

[Mte90]

Yes proceed as anyway we are working to remove it.

[b1ek]

"the amber compiler compiles to .bat files that don't work"

we could display a warning message for windows users when they install it

[hdwalters]

"the amber compiler compiles to .bat files that don't work"

we could display a warning message for windows users when they install it

I'm not even sure if that's necessary. Amber creates Bash output, and advertises itself as a system which does that; if anyone is daft enough to confuse Bash with Batch, that's on them.

Though when we write the documentation (after removing bc and sed dependencies) we can emphasise that it runs on Git Bash, not that it runs on WIndows.