Unexpected behavior when adding external targets to `srcs`

[juanzolotoochin]

The external/<name> part of the source files is removed by tar.bzl when creating a tar archive. For example for the following target:

load("@tar.bzl//:tar.bzl", "mutate", "tar")

tar(
    name = "tar",
    srcs = ["@multitool//tools/gh:gh"]
)

To repro:

$ git clone git@github.com:juanique/bazel-examples.git

$ cd bazel-examples

$ git checkout tar-external-repro

$ cd bazel8/tar_repro

$ bazel build :tar

$ tar -tf bazel-bin/tar.tar

expected output is something along the lines of:

external/rules_multitool++multitool+multitool/tools/
external/rules_multitool++multitool+multitool/tools/gh
external/rules_multitool++multitool+multitool/tools/gh/gh

Actual output is:

tools/
tools/gh/
tools/gh/gh
tar: Removing leading `../' from member names
../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/
../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/rules_multitool++multitool+multitool/
../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/rules_multitool++multitool+multitool/tools/
../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/rules_multitool++multitool+multitool/tools/gh/
../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/rules_multitool++multitool+multitool/tools/gh/gh
../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/_repo_mapping

Untaring the archive:

$ mkdir /tmp/tar_repro

$ tar -xf bazel-bin/tar.tar -C /tmp/tar_repro

tar: Removing leading `../' from member names
tar: ../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/: Member name contains '..'
tar: ../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/rules_multitool++multitool+multitool/: Member name contains '..'
tar: ../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/rules_multitool++multitool+multitool/tools/: Member name contains '..'
tar: ../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/rules_multitool++multitool+multitool/tools/gh/: Member name contains '..'
tar: ../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/rules_multitool++multitool+multitool/tools/gh/gh: Member name contains '..'
tar: ../rules_multitool++multitool+multitool/tools/gh/gh.runfiles/_repo_mapping: Member name contains '..'
tar: Exiting with failure status due to previous errors

$ find /tmp/tar_repro

/tmp/tar_repro
/tmp/tar_repro/tools
/tmp/tar_repro/tools/gh
/tmp/tar_repro/tools/gh/gh