Horizon-QA¶

What it is for¶

Most GTNH regressions are not arithmetic bugs in a pure function. They are machines forming when they should not, recipes running under broken maintenance, outputs routed to the wrong bus, or two mods quietly disagreeing about a tile entity. Horizon-QA exercises those scenarios against the real server and reports them with enough context to act on the XML alone.

Quick example: negative test¶

A common idiom is asserting every tick that something bad does not happen:

@GameTest(template = "ebf_no_coils", timeoutTicks = 60) // (1)!
public static void doesNotFormWithoutCoils(GameTestHelper helper) {
    Multiblock ebf = helper.gtnh().multiblock(at(1, 0, 0));
    helper.onEachTick(() -> // (2)!
        helper.assertFalse(ebf.isFormed(), "EBF formed without coils"));
    helper.succeedAtTimeout(); // (3)!
}

1. template resolves to <holder>:ebf_no_coils, a structure deliberately missing its heating coils.
2. onEachTick re-runs the closure every test tick; a transient true fails immediately, on that tick.
3. succeedAtTimeout passes only if the full window elapses without any assertion firing.

See Negative assertions for the rest of the pattern.

Capabilities¶

Where to go next¶

Getting started walks new authors from "I just cloned the mod" to "my first passing test." Guides cover task-oriented topics: structures, sequences, the GTNH multiblock façade, CI wiring, and failure triage. Reference collects the annotations, commands, JVM flags, and event catalog you will look up most often.