Errors should consistently include filename, line number, and column number

[casey]

I'd like to copy Rust's error messages, and have a line after the error message that starts with a --> and includes the filename, line number, and column number. So this error:

error: Recipe `foo` failed on line 2 with exit code 1

From this justfile:

foo:
  exit 1

Should look like this:

error: Recipe `foo` failed on line 2 with exit code 1
 --> justfile:2:3

This would allow tools to easily extract the error information and jump to the right place in the justfile.

Also, this would make the transition to any kind of multi-justfile world (e.g. includes, modules, etc) much easier, since we would already have the functionality for printing out the filename.

[BeatScherrer]

I try to work up to this since that might already be useful for me.

[casey]

@BeatScherrer Nice! I'd start with tests, add those, and then work from there. You can even open a draft PR with the failing tests, to confirm that they look good.

[Eloitor]

What about allowing a message in case of failure? Something like python's assert

assert expression[, assertion_message]

I don't know what sintax to suggest, but maybe something like:

foo:
  exit 1
  > echo "X failed, do Y and try again"

[casey]

Fixed in #1737.

[BeatScherrer]

Fixed in #1737.

That's really cool to see. I tried to work on this but got lost on how to implement it in the best way since I'm neither familiar with the just code base nor a proficient rust developer.