atf.tests.mk: add bits needed for adding tests that use atf-lua

[ngie]

Wait... Lua? what Lua tests are you planning to add (for the bootloader)?

It's much better to not bolt Lua support on here, but instead in Kyua.

[ngie]

I should have marked this as "Request Changes" in the last message :/...

I can help put this support in Kyua.

[kevans]

In D26930#601401, @ngie wrote:

Wait... Lua? what Lua tests are you planning to add (for the bootloader)?

It's much better to not bolt Lua support on here, but instead in Kyua.

We have Lua in userland now, in the form of /usr/libexec/flua, and we're starting to write both Lua and C modules for flua that need tested; see, for example, D26932 -- it would be a lot more painful to write these tests in C/C++/sh.

[kevans]

Sorry, the key point here is that I don't want to do an indirection through sh to invoke flua and interpret the results, we're going to have enough of these to write that it's much better to have a native library to do this translation.

[kevans]

Upon further inspection, I really like luaunit -- it can do TAP output, so it would be almost no work to hook up to the existing infrastructure. The default output format is actually really nice for diagnosing problems (see: https://luaunit.readthedocs.io/en/latest/#output-formats), which makes it more enticing.

I've submitted an upstream PR[0] to minimize (eliminate?) the need for Kyua work by allowing the TAP_TESTS_LUA infrastructure to use a shebang line like:

[0] https://github.com/bluebird75/luaunit/pull/133

#!/usr/bin/env -S LUAUNIT_DEFAULT_OUTPUT=TAP /usr/libexec/flua

With this, I was able to craft a Kyuafile and test it. While it's not terribly convenient for diagnosing what broke just from the report, IMHO this is sufficient for the initial integration -- I will likely later teach Kyua about the default output format, because it really is pretty good for understanding what went wrong (see the last execution in the below transcript)

root@viper:~/luaunit# cat test_kyua
#!/usr/bin/env -S LUAUNIT_DEFAULT_OUTPUT=TAP /usr/libexec/flua

local lu = require('luaunit')

TestToto = {}
function TestToto:test1_pass()
        local a = 1
        lu.assertEquals(a, 1)
end
function TestToto:test2_fail()
        local a = 1
        lu.assertEquals(a, 2)
end

os.exit(lu.LuaUnit.run())

root@viper:~/luaunit# kyua test -k Kyuafile
test_kyua:main  ->  failed: 1 of 2 tests failed  [0.092s]

Results file id is root_luaunit.20201029-132826-268489
Results saved to /root/.kyua/store/results.root_luaunit.20201029-132826-268489.db

0/1 passed (1 failed)

root@viper:~/luaunit# kyua report --verbose -r /root/.kyua/store/results.root_luaunit.20201029-132826-268489.db
===> Execution context
Current directory: /root/luaunit
Environment variables:
    APPEND_HISTORY=1
    BLOCKSIZE=K
    EDITOR=vim
    HISTFILE=/root/.zsh_history
    HOME=/root
    LANG=en_US.UTF-8
    LOGNAME=kevans
    MAIL=/var/mail/root
    OLDPWD=/root
    PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin:/root/bin:/root/bin
    PWD=/root/luaunit
    SAVEHIST=64
    SHELL=/usr/local/bin/zsh
    SHLVL=1
    TERM=xterm
    USER=root
    _=/usr/bin/kyua
===> test_kyua:main
Result:     failed: 1 of 2 tests failed
Start time: 2020-10-29T13:28:26.458472Z
End time:   2020-10-29T13:28:26.550464Z
Duration:   0.092s

Metadata:
    allowed_architectures is empty
    allowed_platforms is empty
    description is empty
    has_cleanup = false
    is_exclusive = false
    required_configs is empty
    required_disk_space = 0
    required_files is empty
    required_memory = 0
    required_programs is empty
    required_user is empty
    timeout = 300

Standard output:
1..2
# Started on Thu Oct 29 13:28:26 2020
# Starting class: TestToto
ok     1        TestToto.test1_pass
not ok 2        TestToto.test2_fail
#   /root/luaunit/test_kyua:12: expected: 2, actual: 1
# Ran 2 tests in 0.000 seconds, 1 success, 1 failure
===> Failed tests
test_kyua:main  ->  failed: 1 of 2 tests failed  [0.092s]
===> Summary
Results read from /root/.kyua/store/results.root_luaunit.20201029-132826-268489.db
Test cases: 1 total, 0 skipped, 0 expected failures, 0 broken, 1 failed
Start time: 2020-10-29T13:28:26.458472Z
End time:   2020-10-29T13:28:26.550464Z
Total time: 0.092s

root@viper:~/luaunit# /usr/libexec/flua test_kyua
.F
Failed tests:
-------------
1) TestToto.test2_fail
test_kyua:12: expected: 2, actual: 1
stack traceback:
        test_kyua:12: in upvalue 'TestToto.test2_fail'

Ran 2 tests in 0.000 seconds, 1 success, 1 failure

[kevans]

atf-lua was abandoned before introduction