Bazel runs actions in a sandbox by default on Darwin and Linux.
However, the sandboxing was always and *silently* disabled previously,
because a Bazel feature test was always failing. The feature test
involved running `/bin/true` inside a sandbox. But on NixOS,
`/bin/true` does not exist...
This change is going to be required when upgrading to Bazel 0.20.0,
because in the checkPhase we're not wrapping the Bazel binary yet to
set some necessary default arguments.
Bazel supports per-workspace bootstrap scripts at $WORKSPACE_ROOT/
tools/bazel. This adds support for this behavior, which is needed
by many Bazel projects (OSS and private).
This finally fixes the build to avoid having to completely rebuild
bazel from source a second time just to generate the bash completion
script!
It also makes completion actually _work_ for bash users by
correcting the name of the installed script.
Bazel either reuses the `PATH` from the client, or sets a hardcoded
one. The former mode in problematic for build hermeticity. But the
latter is crippled on NixOS, because the hardcoded value is
`/bin:/usr/bin`. So we set the hardcoded value to match what
`customBash` provides. This has the effect of aligning the
environments for `ctx.actions.run` and `ctx.actions.run_shell`, which
were previously distinct (bug).
Bazel is a build tool, much like Make and many others. Like Make, it
should be agnostic to the compiler toolchains the user brings into
scope. Bazel has special rules that encode domain specific knowledge
for how to compile a C++ program, or indeed a Java program and a few
others. But that's not to say that at runtime Bazel should assume
a specific C++ compiler or Java compiler anymore than Make does.
The main impact of this change is that packages that build with Bazel
will have to list the compilers they want in their `buildInputs` or
similar, rather than relying on the `bazel` package pulling them in
transitively.
Removed patches that are purely for testing.
Removed dependencies that seemed to not be needed.
Expand all instances of #!/bin/bash, not just those at the start of scripts.
