Add which command using npm module which

[khuongduybui]

No description provided.

[khuongduybui]

I vetted the source code of the which npm module myself to make sure it's a cross platform, pure-JS implementation.

[nfischer]

Haven't tested this yet, but I'm in favor of re-using existing modules if they're robust enough.

@khuongduybui does this also support things like:

$ export foo="cat"
$ which $foo # outputs path to cat

If so, could you add tests to the pre parser test file?

[dthree]

It should be pretty easy tests for basic functionality. Not trying to re-handle all of the tests that the lib already provides, but a basic test or two that verifies the author didn't butcher the package on the latest update would be good.

[dthree]

Hey looks great, thanks!!!

Added some notes. After this, should be good to merge!

[khuongduybui]

@nfischer: it does work, I'll add a test.
@dthree: thanks for quick response, I will make the suggested changes

[nfischer]

What does this return in the case of which ls? Does this indicate the ls implementation inside cash, or does this return the path to ls on the system? Not sure which behavior would be better in our case, but it's something to think about (and might be worth clarifying in the documentation).

I could see a user being confused about why which ls returns /bin/ls when executing ls actually execute's cash's ls command. But then again, we see the same issue in Bash, since which pwd refers to /bin/pwd and yet the pwd command usually calls a builtin.

[dthree]

Should probably just do the system one - if Cash is installed on Windows globally, it will return the Cash one anyway.

[khuongduybui]

@nfischer: I'm with @dthree here. Wikipedia (which we all agree is the ultimate source of truth, don't we?) says "which is a Unix command used to identify the location of executables." This which command does exactly that.

[nfischer]

Yeah, I'd agree it's probably the better route (I personally hate the which command for this specific reason). This might motivate implementing a command like type to provide nicer semantics (identifies builtins).

[khuongduybui]

@dthree: ready for merge

[dthree]

Thanks! Will do final review shortly.

[dthree]

👍 sorry for the delay