package_dir unexpectedly being stripped from files when it matches Bazel package name

[sloretz]

Minimal reproducible example here: https://github.com/sloretz/rules_pkg_package_dir

Our codebase has a macro that calls pkg_tar with strip_prefix and package_dir set to hardcoded values, sort of like this:

load("@rules_pkg//pkg:tar.bzl", "pkg_tar")

def macro_using_pkg_tar(name, srcs, **kwargs):
    pkg_tar(
        name = name,
        extension = "tar.gz",
        compressor_args = "--fast",
        strip_prefix = "/",
        package_dir = "/data",
        srcs = srcs,
        **kwargs
    )

If I call that macro in the Bazel package //tools then the file in the archive is put at data/tools/foo.txt. If I call the same macro in the Bazel package //data then the file in the archive is data/foo.txt with rules_pkg 1.0.1, and data/data/foo.txt with rules_pkg 0.9.1.

I expect the 0.9.1 behavior. Any ideas on workarounds to prevent package_dir from being stripped in 1.0.1?

Possibly caused by #749?