| """ |
| select_file() build rule implementation. |
| |
| Selects a single file from the outputs of some target by given relative path. |
| """ |
| |
| def _impl(ctx): |
| if ctx.attr.subpath and len(ctx.attr.subpath) == 0: |
| fail("Subpath can not be empty.") |
| |
| out = None |
| canonical = ctx.attr.subpath.replace("\\", "/") |
| for file_ in ctx.attr.srcs.files.to_list(): |
| if file_.path.replace("\\", "/").endswith(canonical): |
| out = file_ |
| break |
| if not out: |
| files_str = ",\n".join([ |
| str(f.path) |
| for f in ctx.attr.srcs.files.to_list() |
| ]) |
| fail("Can not find specified file in [%s]" % files_str) |
| return [DefaultInfo(files = depset([out]))] |
| |
| select_file = rule( |
| implementation = _impl, |
| doc = "Selects a single file from the outputs of some target \ |
| by given relative path", |
| attrs = { |
| "srcs": attr.label( |
| allow_files = True, |
| mandatory = True, |
| doc = "The target producing the file among other outputs", |
| ), |
| "subpath": attr.string( |
| mandatory = True, |
| doc = "Relative path to the file", |
| ), |
| }, |
| ) |
