1 files changed, 22 insertions, 0 deletions
diff --git a/src/LivingVillage.Desktop.Tests/PrototypeTests.fs b/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
index 5a40868..ece7b23 100644
--- a/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
+++ b/src/LivingVillage.Desktop.Tests/PrototypeTests.fs
@@ -737,6 +737,28 @@ type PrototypeTests () =
         Assert.AreEqual<float32>(TitleScreen.entranceProgress 37L, TitleScreen.entranceProgress 37L)
 
     [<TestMethod>]
+    member _.ProceduralMapGeneratesByteIdenticalTerrainFromSameSeed () =
+        let first = ProceduralMap.generate (uint64 4242)
+        let second = ProceduralMap.generate (uint64 4242)
+        Assert.AreEqual<int>(first.Tiles.Length, second.Tiles.Length)
+        let snapshot = Array.copy first.Tiles
+        for i in 0 .. snapshot.Length - 1 do
+            Assert.AreEqual<int>(snapshot.[i], second.Tiles.[i], (sprintf "tile %d diverged" i))
+
+        // Different seed must produce different terrain (sanity).
+        let other = ProceduralMap.generate (uint64 777)
+        let differs = [0 .. snapshot.Length - 1] |> List.tryFind (fun i -> other.Tiles.[i] <> snapshot.[i])
+        Assert.IsTrue(differs.IsSome, "different seed should carve different terrain")
+
+        // Village core stays walkable: no water/peat inside the handcrafted core rect.
+        let coreBad =
+            [ for y in ProceduralMap.villageCoreMinY .. ProceduralMap.villageCoreMaxY do
+                for x in ProceduralMap.villageCoreMinX .. ProceduralMap.villageCoreMaxX do
+                    let code = first.Tiles.[y * ProceduralMap.width + x]
+                    if code = ProceduralMap.GroundTile.Water || code = ProceduralMap.GroundTile.Peat then yield (x, y, code) ]
+        Assert.AreEqual<(int * int * int) list>([], coreBad)
+
+    [<TestMethod>]
     member _.WorldPanelDoesNotRenderA永久KeyList () =
         let world = Sim.initialWorldN 42UL 0
         let lines = M5Interaction.panelLines world M5Interaction.initial