cmd/dist: drop host test support
Host tests are used for emulated builders that use cross-compilation.
Today, this is the android-{386,amd64}-emu builders and all wasm
builders. These builders run all.bash on a linux/amd64 host to build
all packages and most tests for the emulated guest, and then run the
resulting test binaries inside the emulated guest. A small number of
test packages are “host tests”: these run on the host rather than the
guest because they invoke the Go toolchain themselves (which only
lives on the host) and run the resulting binaries in the guest.
However, this host test mechanism is barely used today, despite being
quite complex. This complexity is also causing significant friction to
implementing structured all.bash output.
As of this CL, the whole host test mechanism runs a total of 10 test
cases on a total of two builders (android-{386,amd64}-emu). There are
clearly several tests that are incorrectly being skipped, so we could
expand it to cover more test cases, but it would still apply to only
two builders. Furthermore, the two other Android builders
(android-{arm,arm64}-corellium) build the Go toolchain directly inside
Android and also have access to a C toolchain, so they are able to get
significantly better test coverage without the use of host tests. This
suggests that the android-*-emu builders could do the same. All of
these tests are cgo-related, so they don't run on the wasm hosts
anyway.
Given the incredibly low value of host tests today, they are not worth
their implementation complexity and the friction they cause. Hence,
this CL drops support for host tests. (This was also the last use of
rtSequential, so we drop support for sequential tests, too.)
Fixes #59999.
Change-Id: I3eaca853a8907abc8247709f15a0d19a872dd22d
Reviewed-on: https://go-review.googlesource.com/c/go/+/492986
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>