Change dash to underscore in generated filenames

[mjduijn]

The generated rust file for my-file.proto is my_file.rs.
Declared outputs for *_proto and *_grpc rules should reflect this.

[mfarrugi]

This function should remain a helper that takes '/some/path/file.txt' and returns 'file', can you move the replace to L52?

paths = ["%s/%s" % (output_dir, file_stem(i).replace("-", "_") for i in protos.to_list()]

[mjduijn]

The same functionality is needed for generating the module names for lib.rs (see proto/proto.bzl).
The function doesn't appear to be used in other cases.
Mind if I just rename the function to generated_file_stem instead?

[mfarrugi]

Yes that makes sense. (I didn't notice the other usages.)

[mfarrugi]

How did you notice this?

[mjduijn]

We have some files with dashes as delimiter, so when trying to generate the code, I got the following error

ERROR: <path-to-build-file> output '<path-to-expected-output>' was not created
ERROR: <path-to-build-file>: not all outputs were created or valid Target <path-to-target> failed to build

I've written a couple of these kinds of bazel rules for generating gRPC bindings, so I was familiar with the error.

[mfarrugi]

Thanks