KTAP Test Output

When SlopOS boots with tests=on, the kernel emits a KTAP-compatible stream on the serial console. The host test runner parses that stream and renders progress, failure details, and optional JSONL events.

Phases

Every harness line starts with KTAP\t. Ordinary kernel log lines may intermix and are ignored by the parser outside diagnostic blocks.

Header

Each phase begins with:

KTAP	TAP version 14
KTAP	1..N

N is the number of tests selected for that phase after filters.

Result Lines

KTAP	ok 17 - slopos_mm::tests::heap::test_heap_kzalloc_zeroed # time_ms=3
KTAP	not ok 42 - slopos_core::tests::sched::test_priority_inversion # time_ms=11
KTAP	ok 18 - slopos_net::tests::tcp_live::test_loopback_handshake # SKIP test returned Skipped

Slow tests add OVER_TIME. Expected panic tests add EXPECTED_PANIC.

Diagnostics

Failures include a YAML diagnostic block:

KTAP	  ---
KTAP	  outcome: Fail
KTAP	  file: <source-path>:1832
KTAP	  log: |
KTAP	   captured klog line
KTAP	  ...

Verbose passing tests may include a log: | block without outcome or file. Logs may contain trim markers when the captured klog exceeds the per-test cap or the per-CPU log ring overflows.

Userland Subtests

Userland test binaries report subtests through the test-report syscall. The kernel emits them indented before the parent result:

KTAP	  ok 1 - alloc_basic
KTAP	  not ok 2 - alloc_zero # zero-size returned null
KTAP	ok 5 - utest_heap_allocator # time_ms=234

The host parser buffers subtests and attaches them to the next top-level result.

Footer And Exit

Each phase ends with:

KTAP	# elapsed_ms=14238 pass=2391 fail=1 skip=0 over_time=14

When all test phases finish, the kernel writes to isa-debug-exit: status 0 for green and status 1 for failure. QEMU maps those to host exit statuses that the host runner normalizes.