[bug] ppx_flags no longer allows passing arguments to ppxs

[jaredly]

Not sure when this happened, but it's broken again 🙃
If I have "ppx-flags": ["./some-ppx --an-arg"] I get the error:

> bsb -make-world

ninja: error: rebuilding 'build.ninja': '/path/to/some-ppx --some-arg', needed by 'src/Hello.mlast', missing and no known rule to make it

Apparently ninja is being passed the ppx path and the argument as though it's a single file that is a dependency.

(bs-platform version 5.0.4)

[bobzhang]

does this work for you:

"ppx-flags" : ["./some-ppx", "--an-arg"]

[bobzhang]

The change is that recently we did some check to enforce that ppx binary actually exists for better error message

[jaredly]

@bobzhang nope that doesn't work -- --an-arg is treated as a separate ppx

[bobzhang]

The sanity check was introduced since @rickyvetter found when ppx binary changes, the files won't get rebuilt. Since user could pass a list of ppxes, so the ideal config would be

[ ["ppx1", ...ppx1-args], ["ppx2", ... ppx2-args], ...]

I am going to relax such check. For your own temporary work around, since you own your own ppx, you can pass it without arguments.

I did not support ppx with arguments since it is really complicated to make it work with Windows etc.

[bobzhang]

@jaredly I changed the schema to support ppx arguments, see this: e9f68ec

[bobzhang]

merged in master

[jaredly]

thanks!