From e215d7190bca9ba3409f3f73ab8f983d0bf419e0 Mon Sep 17 00:00:00 2001
From: DualFroz <me@dualfroz.com>
Date: Sat, 12 Sep 2026 15:59:34 +0200
Subject: [PATCH] test: cover testNetherGen

---
 tests/testNetherGen.cpp | 148 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 148 insertions(+)

diff --git a/tests/testNetherGen.cpp b/tests/testNetherGen.cpp
index f52b285..cca0474 100644
--- a/tests/testNetherGen.cpp
+++ b/tests/testNetherGen.cpp
@@ -164,3 +164,151 @@ VF_TEST(netherLavaSeaLeavesNoAirBelowItsSurface) {
     CHECK(lavaSamples > 0);
 }
 
+VF_TEST(netherCarriesAllFourBiomes) {
+    NetherGenerator generator;
+    std::set<int> seen;
+    for (int gx = -900; gx <= 900; gx += 17)
+        for (int gz = -900; gz <= 900; gz += 17)
+            seen.insert(static_cast<int>(generator.biomeAt(gx, gz)));
+    CHECK_EQ(seen.size(), static_cast<std::size_t>(NetherBiome::Count));
+}
+
+VF_TEST(netherBiomesLayDownTheirOwnSurfaceBlocks) {
+    NetherGenerator generator;
+    int soulSandTops = 0;
+    int basaltTops = 0;
+    int mossTops = 0;
+    int foreignSoulTops = 0;
+
+    for (int gx = -600; gx <= 600; gx += 13) {
+        for (int gz = -600; gz <= 600; gz += 13) {
+            NetherColumn column = generator.columnAt(gx, gz);
+            Block top = generator.blockAt(column, gx, column.floorHeight, gz);
+            switch (column.biome) {
+                case NetherBiome::SoulSandValley:
+                    if (top == Block::SoulSand) ++soulSandTops;
+                    if (top == Block::Basalt || top == Block::Moss) ++foreignSoulTops;
+                    break;
+                case NetherBiome::BasaltDeltas:
+                    if (top == Block::Basalt) ++basaltTops;
+                    break;
+                case NetherBiome::CrimsonForest:
+                    if (top == Block::Moss) ++mossTops;
+                    break;
+                default:
+                    break;
+            }
+        }
+    }
+    CHECK(soulSandTops > 0);
+    CHECK(basaltTops > 0);
+    CHECK(mossTops > 0);
+    CHECK_EQ(foreignSoulTops, 0);
+}
+
+VF_TEST(netherSoulSandValleyFillsItselfWithSoulSoil) {
+    NetherGenerator generator;
+    int columnX = 0, columnZ = 0;
+    CHECK(findColumnWithBiome(generator, NetherBiome::SoulSandValley, columnX, columnZ) == 1);
+
+    World world;
+    generator.generateColumn(world, columnX, columnZ);
+    std::map<Block, int> tally = censusColumn(world, columnX, columnZ, generator.settings().ceilingY);
+
+    CHECK(countOf(tally, Block::SoulSand) > 0);
+    CHECK(countOf(tally, Block::SoulSoil) > 0);
+    CHECK_EQ(countOf(tally, Block::Basalt), 0);
+}
+
+VF_TEST(netherStocksQuartzGlowstoneAndLava) {
+    NetherGenerator generator;
+    World world;
+    for (int columnX = -2; columnX <= 2; ++columnX)
+        for (int columnZ = -2; columnZ <= 2; ++columnZ)
+            generator.generateColumn(world, columnX, columnZ);
+
+    int quartz = 0, glowstone = 0, lava = 0, netherrack = 0, magma = 0;
+    for (int gx = -32; gx < 48; ++gx) {
+        for (int gz = -32; gz < 48; ++gz) {
+            for (int gy = 0; gy < generator.settings().ceilingY; ++gy) {
+                switch (world.blockAt(gx, gy, gz)) {
+                    case Block::NetherQuartzOre: ++quartz; break;
+                    case Block::Glowstone: ++glowstone; break;
+                    case Block::Lava: ++lava; break;
+                    case Block::Netherrack: ++netherrack; break;
+                    case Block::Magma: ++magma; break;
+                    default: break;
+                }
+            }
+        }
+    }
+    CHECK(quartz > 0);
+    CHECK(glowstone > 0);
+    CHECK(magma > 0);
+    CHECK(lava > 1000);
+    CHECK(netherrack > quartz);
+}
+
+VF_TEST(netherGlowstoneClingsToTheRoofNotTheFloor) {
+    NetherGenerator generator;
+    World world;
+    for (int columnX = -1; columnX <= 1; ++columnX)
+        for (int columnZ = -1; columnZ <= 1; ++columnZ)
+            generator.generateColumn(world, columnX, columnZ);
+
+    int lowGlowstone = 0;
+    int highGlowstone = 0;
+    for (int gx = -16; gx < 32; ++gx) {
+        for (int gz = -16; gz < 32; ++gz) {
+            NetherColumn column = generator.columnAt(gx, gz);
+            for (int gy = 0; gy < generator.settings().ceilingY; ++gy) {
+                if (world.blockAt(gx, gy, gz) != Block::Glowstone) continue;
+                if (gy >= column.ceilingHeight - 4) ++highGlowstone;
+                else ++lowGlowstone;
+            }
+        }
+    }
+    CHECK(highGlowstone > 0);
+    CHECK_EQ(lowGlowstone, 0);
+}
+
+VF_TEST(netherCavesCarveRockWithoutEmptyingIt) {
+    NetherGenerator generator;
+    int carved = 0;
+    int total = 0;
+    for (int gx = -200; gx <= 200; gx += 7) {
+        for (int gz = -200; gz <= 200; gz += 7) {
+            for (int gy = 8; gy < 120; gy += 9) {
+                if (generator.isCarved(gx, gy, gz)) ++carved;
+                ++total;
+            }
+        }
+    }
+    CHECK(carved > 0);
+    CHECK(carved < total / 4);
+}
+
+VF_TEST(netherDecorationCanBeSwitchedOffWithoutChangingTheRock) {
+    NetherGenerator::Params bare;
+    bare.decorate = false;
+    NetherGenerator plain(bare);
+    NetherGenerator decorated;
+
+    World plainWorld, decoratedWorld;
+    plain.generateColumn(plainWorld, 1, 1);
+    decorated.generateColumn(decoratedWorld, 1, 1);
+
+    int differences = 0;
+    int netherrackKept = 0;
+    for (int gx = 16; gx < 32; ++gx) {
+        for (int gz = 16; gz < 32; ++gz) {
+            for (int gy = 0; gy < 128; ++gy) {
+                Block bareBlock = plainWorld.blockAt(gx, gy, gz);
+                if (bareBlock != decoratedWorld.blockAt(gx, gy, gz)) ++differences;
+                else if (bareBlock == Block::Netherrack) ++netherrackKept;
+            }
+        }
+    }
+    CHECK(differences > 0);
+    CHECK(netherrackKept > 1000);
+}