Always use the rule label as a directory and then put all files under that
directory.

Gracefully handles dot-files.

Be defensive on the kernel name

Matthew Clarkson authored Dec 13, 2023 and Matthew Clarkson committed Dec 13, 2023

This forces the `@which-echo` repository to run which will fail
when there is no `echo` on `PATH`. That is the case on Windows.

It is not guaranteed that `echo` is on `PATH` on Linux but highly
likely.

`ctx.action.symlink` does not create a symlink without developer mode.

Help out the rule by explicitly creating a hardlink.

Splitting out `resolved`/`which` repository rules makes sense.

It prevents any missing tools from raising an error in the toolchain resolution
rather than later via the stub.

This is _much_ more **user** friendly.

Including the `resolved` target in the local repository was more
**developer** friendly as it negated the need for two repositories.

We want to be **user** friendly.

`use_repo_rule` never made it into Bazel 6.4.0

No versions for now as we only need the unversioned to describe
some Rust downloaded binaries.

Matthew Clarkson authored Dec 11, 2023 and Matthew Clarkson committed Dec 11, 2023

`ctx.action.symlink` does not create a symlink without developer mode.

Help out the rule by explicitly creating a hardlink.

This is what engineers expect.

Adding folders prevents conflicts with other rules.

Matthew Clarkson authored Dec 11, 2023 and Matthew Clarkson committed Dec 11, 2023

This is needed when taking the tool via path in a genrule or script action.

The tool cannot be executed directly.

Matthew Clarkson authored Dec 08, 2023 and Matthew Clarkson committed Dec 08, 2023

This is a bit of a hack for Windows.

We want to be able to do:

    bazelisk run -- @echo//:entrypoint

However, because there is no extension on `entrypoint` which is
actually a hardlink/symlink to `entrypoint.bat` Bazel puts it through
`CreateProcessW` and attempts to start it as a portable executable
(PE/COFF).

The launcher is a bit of C# code to create an `exe` that uses argument
zero to find the corresponding `.bat` script and launches that instead.

The resulting executable can be hardlinked/symlinked from anywhere that
has a batch script to provide a executable launcher for the script.

We can then have nice labels on both POSIX/Windows.

Allows the `load` graph to be "load what you use" rather than pulling
in all `.bzl` files in a single `def.bzl` file.