MirrorImageShotsProduceStatisticallyMirroredDamage compared per-cell armour
damage SUMS between a bearing and its mirror, using heavy (1000) uniform
armour. That armour never depleted, so no cell's absorption ever competed
with another lane's, and the test could not see the one thing the operator's
ruling is about: two lanes racing for one cell's finite armour under the old
one-cell spacing. Renamed to MirrorImageShotsProduceStatisticallyMirroredHullDamage,
it now resets a small, finite armour value before every individual shot (so
the race is live on every trial) and compares aggregate HULL damage, where a
lost race's leftover actually lands.
Finding, reported rather than hidden: even with this fix, the test does not
fail under the reverted one-cell spacing. Reasoning checked against measured
behaviour: FireControl.Apply always processes lanes in a fixed index order
(li ascending, i.e. lateral increasing), never based on the bearing's sign.
Over many INDEPENDENTLY random lateral draws, a bearing and its mirror sample
statistically equivalent distributions of "which side's lane goes first" --
the fixed-index tie-break rule respects the mirror symmetry in aggregate, so
independently-drawn trials wash out the order-dependent bias that Soul's own
LaneOrderDemo probe found (that probe compares ascending vs descending
processing of the SAME committed shot, not independently-drawn mirrored
bearings). A production-level test that reliably fails under the old spacing
for this specific property would need to force an exact, deterministic
lateral for two geometrically mirrored shots, which is not reachable through
Fire/Commit without reflection (Commit's lateral draw is randomised, and
Apply is private). NoCellIsStruckByTwoLanesAtAnAngledBearing and
FootprintWidensAtAnAngledBearingComparedToAxisAligned remain the two tests
that actually discriminate the ruling behaviourally (confirmed failing under
a hand-reverted one-cell spacing). The mirror test stays in the suite as a
true, currently-passing invariant and useful regression coverage, not as a
defense of this specific ruling.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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