Enable test builds with --bootstrap

[am11]

• Enable UseBootstrap in libraries.tests
• Enable --use-bootstrap in runtime testss (src/tests/build.sh --use-bootstrap --cross --riscv64 ...)
• Use local target pack infra from eng/ in src/tests (once discussed with @hoyosjs Enable building tests with UseLocalAppHostPack=true #99354 (review))

Fixes #115622

[am11]

For community platforms, this is the cross-build workflow for runtime development/testing:

os=linux
arch=riscv64

# ROOTFS_DIR is set

# cross-build product, --bootstrap
./build.sh clr+libs --cross --arch $arch --os $os --bootstrap

# for rebuild (e.g. after editing code), --use-bootstrap
./build.sh clr+libs --cross --arch $arch --os $os --use-bootstrap

# runtime tests cross-build, --use-bootstrap
src/tests/build.sh -cross -$arch -$os -p:LibrariesConfiguration=Debug --use-bootstrap

# libraries tests cross-build, --use-bootstrap
./build.sh libs.tests --cross --arch $arch --os $os --use-bootstrap

cc:
riscv64: @clamp03, @dotnet/samsung
loongarch64: @LuckyXu-HF, @shushanhf
illumos: @gwr
FreeBSD: @Thefrank, @sec
Haiku: @trungnt2910
OpenBSD: @sethjackson

[jkotas]

Update PR title to match the content?

[am11]

Update PR title to match the content?

Ah, it somehow used cached title from my previous PR.

[Thefrank]

So if I am reading this correctly, after this PR, I can:

• Use Enable test builds with --bootstrap #127909 (comment) to make nightly runtime tests for freebsd-ARCH
• Copy over zipped tests to freebsd system (assuming /p:ArchiveTests still exists if not done automatically)
• Run
• ...and finally enjoy easy nightly builds

This is pretty awesome. I gave up trying to do nightly runtime builds / tests more than a year ago because it was such a hassle natively.

[am11]

• Use Enable test builds with --bootstrap #127909 (comment) to make nightly runtime tests for freebsd-ARCH
• Copy over zipped tests to freebsd system (assuming /p:ArchiveTests still exists if not done automatically)
• Run
• ...and finally enjoy easy nightly builds

Yes, it exists, e.g. in the build container:

$ docker run --rm -v$(pwd):/runtime -w /runtime -e ROOTFS_DIR=/crossrootfs/<xxx> -it <container-urn>
$ os=<yyy>; arch=<xxx>;
$ ./build.sh clr+libs --cross --arch $arch --os $os --bootstrap
$ ./build.sh libs.tests --cross --arch $arch --os $os --use-bootstrap -p:ArchiveTests=true

from host:

# pack and upload testhost to the machine
$ tar -czf testhost_net11.0-<yyy>-Debug-<xxx>.tar.gz artifacts/bin/testhost/net11.0-<yyy>-Debug-<xxx>
$ scp testhost_net11.0-<yyy>-Debug-<xxx>.tar.gz $TargetMachine:/tmp

# copy tests to the machine
$ scp artifacts/helix/tests/linux.AnyCPU.Debug/System.Text.RegularExpressions.Unit.Tests.zip $TargetMachine:/tmp

# usage
$ ssh $TargetMachine

$ mkdir testhost
$ tar -xzf /tmp/testhost_net11.0-<yyy>-Debug-<xxx>.tar.gz -C testhost
$ mkdir regex-tests
$ cd $_
$ unzip System.Text.RegularExpressions.Unit.Tests.zip

$ ./RunTests.sh --runtime-path ~/testhost/artifacts/bin/testhost/net11.0-<yyy>-Debug-<xxx>

For runtime tests, after the build, just pack and upload artifacts/tests/coreclr/<yyy>.<xxx>.Debug to remove machine and after extraction, and then e.g. to run interpreter tests: CORE_ROOT=$(pwd)/artifacts/tests/coreclr/<yyy>.<xxx>.Debug/Tests/Core_Root DOTNET_TieredCompilation=0 artifacts/tests/coreclr/<yyy>.<xxx>.Debug/JIT/Interpreter/InterpreterTester/InterpreterTester.sh

---

The only thing which doesn't work in general (unrelated to bootstrap) is building / packing individual library tests. e.g. the zip file generated by ./dotnet.sh build -p:UseBootstrap=true -p:ArchiveTests=true -p:TargetOS=$os -p:TargetArchitecture=$arch -p:CrossBuild=true src/libraries/System.Formats.Nrbf/tests misses xunit.console.runtimeconfig.json etc. so it's unusble. Perhaps we need to pass more properties? I just built the. whole libs.tests subset which is exercised in the CI.