From f00b6650df29fb038f7510fb2bb83f152c5e2007 Mon Sep 17 00:00:00 2001
From: DualFroz <me@dualfroz.com>
Date: Fri, 11 Sep 2026 19:00:19 +0200
Subject: [PATCH] test: cover withEnchant and hitsUntilBroken

---
 tests/testItemStack.cpp | 160 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 160 insertions(+)
 create mode 100644 tests/testItemStack.cpp

diff --git a/tests/testItemStack.cpp b/tests/testItemStack.cpp
new file mode 100644
index 0000000..5d8ec2c
--- /dev/null
+++ b/tests/testItemStack.cpp
@@ -0,0 +1,160 @@
+#include "testHarness.h"
+#include "vf/ItemStack.h"
+
+#include <string>
+#include <vector>
+
+using namespace vf;
+
+namespace {
+
+EnchantSet withEnchant(EnchantKind kind, int level) {
+    EnchantSet set;
+    addEnchant(set, kind, level);
+    return set;
+}
+
+int hitsUntilBroken(MetaStack stack, uint32_t seed, int limit) {
+    uint32_t rng = seed;
+    for (int hits = 1; hits <= limit; ++hits) {
+        WearResult wear = damageStack(stack, 1, rng);
+        if (wear == WearResult::Broke) return hits;
+    }
+    return -1;
+}
+
+} // namespace
+
+VF_TEST(stackLimitFollowsTheItemKindRatherThanAFixedNumber) {
+    CHECK_EQ(makeStack(ItemId::Stone, 1).maxCount(), 64);
+    CHECK_EQ(makeStack(ItemId::Bread, 1).maxCount(), 64);
+    CHECK_EQ(makeTool(ItemId::IronPickaxe).maxCount(), 1);
+    CHECK_EQ(stackLimitFor(ItemId::None), 0);
+
+    MetaStack overfilled = makeStack(ItemId::Stone, 200);
+    CHECK_EQ(overfilled.count, 64);
+    CHECK(overfilled.full());
+    CHECK_EQ(overfilled.room(), 0);
+}
+
+VF_TEST(aFreshToolCarriesItsFullDurabilityAndNothingElse) {
+    MetaStack pickaxe = makeTool(ItemId::DiamondPickaxe);
+    CHECK_EQ(pickaxe.count, 1);
+    CHECK_EQ(pickaxe.meta.durability.max, toolMaxDurability(ItemId::DiamondPickaxe));
+    CHECK_EQ(pickaxe.meta.durability.used, 0);
+    CHECK(pickaxe.meta.durability.damageable());
+    CHECK(!pickaxe.meta.durability.broken());
+    CHECK_NEAR(pickaxe.meta.durability.fraction(), 1.0f, 0.0001f);
+    CHECK(pickaxe.meta.pristine());
+
+    MetaStack notATool = makeTool(ItemId::Stone);
+    CHECK(notATool.empty());
+}
+
+VF_TEST(twoUsedToolsOnlyMergeWhenTheirWearIsIdentical) {
+    uint32_t rng = 7u;
+    MetaStack fresh = makeTool(ItemId::IronPickaxe);
+    MetaStack used = makeTool(ItemId::IronPickaxe);
+    damageStack(used, 5, rng);
+
+    CHECK(!stacksMergeable(fresh, used));
+    CHECK(stacksMergeable(fresh, makeTool(ItemId::IronPickaxe)));
+
+    MetaStack sameWear = makeTool(ItemId::IronPickaxe);
+    sameWear.meta.durability.used = used.meta.durability.used;
+    CHECK(stacksMergeable(used, sameWear));
+
+    StackTransfer refused = transferAll(used, fresh);
+    CHECK(refused.incompatible);
+    CHECK_EQ(refused.moved, 0);
+    CHECK_EQ(fresh.count, 1);
+    CHECK_EQ(used.count, 1);
+}
+
+VF_TEST(anEnchantedSwordNeverMergesWithAPlainOne) {
+    MetaStack plain = makeTool(ItemId::DiamondSword);
+    MetaStack enchanted = makeEnchantedTool(ItemId::DiamondSword,
+                                            withEnchant(EnchantKind::Sharpness, 3));
+
+    CHECK(!stacksMergeable(plain, enchanted));
+    CHECK(!stacksIdentical(plain, enchanted));
+
+    MetaStack sameEnchant = makeEnchantedTool(ItemId::DiamondSword,
+                                              withEnchant(EnchantKind::Sharpness, 3));
+    CHECK(stacksMergeable(enchanted, sameEnchant));
+
+    MetaStack otherLevel = makeEnchantedTool(ItemId::DiamondSword,
+                                             withEnchant(EnchantKind::Sharpness, 2));
+    CHECK(!stacksMergeable(enchanted, otherLevel));
+}
+
+VF_TEST(enchantmentOrderDoesNotChangeStackIdentity) {
+    EnchantSet forward;
+    addEnchant(forward, EnchantKind::Unbreaking, 2);
+    addEnchant(forward, EnchantKind::Efficiency, 4);
+
+    EnchantSet reversed;
+    addEnchant(reversed, EnchantKind::Efficiency, 4);
+    addEnchant(reversed, EnchantKind::Unbreaking, 2);
+
+    CHECK(sameEnchants(forward, reversed));
+    CHECK(stacksMergeable(makeEnchantedTool(ItemId::IronPickaxe, forward),
+                          makeEnchantedTool(ItemId::IronPickaxe, reversed)));
+
+    EnchantSet shorter = withEnchant(EnchantKind::Efficiency, 4);
+    CHECK(!sameEnchants(forward, shorter));
+}
+
+VF_TEST(aCustomNameKeepsAStackOnItsOwn) {
+    MetaStack named = makeNamedStack(ItemId::Stone, 10, "Cornerstone");
+    MetaStack plain = makeStack(ItemId::Stone, 10);
+
+    CHECK_EQ(named.count, 1);
+    CHECK_EQ(named.maxCount(), 1);
+    CHECK(!stacksMergeable(named, plain));
+    CHECK(stacksMergeable(named, makeNamedStack(ItemId::Stone, 1, "Cornerstone")));
+    CHECK(!stacksMergeable(named, makeNamedStack(ItemId::Stone, 1, "Keystone")));
+}
+
+VF_TEST(transferMovesOnlyWhatFitsAndLeavesTheRestBehind) {
+    MetaStack source = makeStack(ItemId::Cobblestone, 40);
+    MetaStack destination = makeStack(ItemId::Cobblestone, 40);
+
+    StackTransfer moved = transferAll(source, destination);
+    CHECK_EQ(moved.moved, 24);
+    CHECK(moved.destinationFull);
+    CHECK(!moved.sourceEmptied);
+    CHECK_EQ(destination.count, 64);
+    CHECK_EQ(source.count, 16);
+
+    MetaStack elsewhere;
+    StackTransfer rest = transferAll(source, elsewhere);
+    CHECK_EQ(rest.moved, 16);
+    CHECK(rest.sourceEmptied);
+    CHECK(source.empty());
+    CHECK_EQ(elsewhere.count, 16);
+    CHECK(elsewhere.item == ItemId::Cobblestone);
+}
+
+VF_TEST(transferRefusesAnIncompatibleDestinationWithoutMovingAnything) {
+    MetaStack planks = makeStack(ItemId::Planks, 12);
+    MetaStack stone = makeStack(ItemId::Stone, 5);
+
+    StackTransfer blocked = transferAll(planks, stone);
+    CHECK(blocked.incompatible);
+    CHECK_EQ(blocked.moved, 0);
+    CHECK_EQ(planks.count, 12);
+    CHECK_EQ(stone.count, 5);
+}
+
+VF_TEST(splittingAStackLeavesTheLargerHalfBehind) {
+    MetaStack odd = makeStack(ItemId::Sand, 7);
+    MetaStack taken = splitHalf(odd);
+    CHECK_EQ(taken.count, 4);
+    CHECK_EQ(odd.count, 3);
+
+    MetaStack single = makeStack(ItemId::Sand, 1);
+    MetaStack lastOne = splitHalf(single);
+    CHECK_EQ(lastOne.count, 1);
+    CHECK(single.empty());
+