Resolve Local Dependencies From Bundle Path

[rawkode]

Fixes #22

[SeanTAllen]

@rawkode looks like there is a test failure.

[rawkode]

Hi @SeanTAllen,

This should build successfully now. One thing I'd appreciate some guidance on though:

The following works, without error:

Path.join(tmp.path, "../local/a") + ":" +

but the following fails:

tmp.join("../local/a")?.path

Which I find strange, as the following works:

```pony
tmp.join("./local/a")?.path

I don't understand why 😕

Is this a bug in the join code, perhaps?

[SeanTAllen]

Path.join is building a path from a string (tmp.path)

tmp was probably created with FilePath capability which doesn't allow you to use it to access directories above that level. See create inside of FilePath which gets called by your tmp.join.

    path = match base
      | let b: FilePath =>
        if not b.caps(FileLookup) then
          error
        end

        let tmp_path = Path.join(b.path, path')
        caps.intersect(b.caps)

        if not tmp_path.at(b.path, 0) then
          error
        end
        tmp_path
      | let b: AmbientAuth =>
        Path.abs(path')
      end

[rawkode]

@SeanTAllen I believe this PR is good to go, regardless of my question (Hopefully 👍 )

[SeanTAllen]

Before this is merged, we need a good release message for this as it is a breaking change.

@rawkode do you feel up to writing that? If yes, have a go and put it in a comment here. Ideally, we'd want an explanation of what changed, why, and before and after examples of what what one would need to change (if applicable).

[rawkode]

Resolve Local Dependencies From Bundle Path

Previously, if a stable command was executed deeper in the directory hierarchy than the bundle.json files, relative dependencies would be resolved from where the command was executed.

Now, all relative dependencies are resolved relatively from the bundle.json directory.

This resolution is more intuitive and predictable.

[rawkode]

SYN

[SeanTAllen]

Thanks @rawkode