In this commit:
- change unittest.bzl to declare a named output
file instead of relying on the deprecated [1]
default output name (ctx.outputs.executable).
- define a new toolchain_type and toolchain rules
for cmd.exe and for Bash (basically Windows and
non-Windows)
- register the new toolchains in workspace.bzl
- let unittest.make-created test rules require the
new toolchain_type
- write the test output script as a Windows batch
script or as a Shell script, depending on the
selected toolchain
This PR enables the Bazel team to break the Bash
dependency (for test execution) on Windows, and
can run Starlark unittests with the new,
Windows-native test wrapper (still under
development).
See https://github.com/bazelbuild/bazel/issues/5508
