Item entities

tests/item_entity_test.ts

@@ -0,0 +1,87 @@
+import { assert, assertEquals } from "@std/assert";
+import { ItemStack } from "$/common/inventory.ts";
+import { test_game } from "./helpers.ts";
+
+// a stone floor at y 99 so drops have something to land on, high above the generated terrain
+function build_floor(game: Awaited<ReturnType<typeof test_game>>["game"]) {
+	for (let x = -3; x <= 9; x++) {
+		for (let z = -4; z <= 4; z++) {
+			game.set_block(x, 99, z, "bworld:stone");
+		}
+	}
+}
+
+const inventory_count = (
+	messages: { type: string; container?: string; items?: ({ id: string; count: number } | null)[] }[],
+	id: string,
+) => (messages.filter((m) => m.type === "container" && m.container === "inventory").at(-1)?.items ?? [])
+	.reduce((sum, item) => sum + (item?.id === id ? item.count : 0), 0);
+
+Deno.test("breaking a block drops its item, which lands and gets picked up by walking to it", async () => {
+	const { game, take, send, join } = await test_game("mods");
+	join(1, "alice");
+	build_floor(game);
+	game.set_block(5, 100, 0, "bworld:dirt");
+	send(1, { type: "move", x: 0.5, y: 100, z: 0.5, yaw: 0, pitch: 0 });
+	take(1);
+
+	send(1, { type: "break_block", x: 5, y: 100, z: 0 });
+	const messages = take(1);
+	const added = messages.find((m) => m.type === "add_entity");
+	assertEquals(added?.entity.kind, "item");
+	assertEquals(added?.entity.item, { id: "bworld:dirt", count: 1 });
+	assertEquals(inventory_count(messages, "bworld:dirt"), 0, "it drops instead of going into the inventory");
+
+	for (let i = 0; i < 40; i++) game.tick();
+	const [item] = game.item_entities();
+	assert(item.on_ground, "it fell onto the floor");
+	assertEquals(item.y, 100);
+	assert(Math.abs(item.x - 5.5) < 1.5 && Math.abs(item.z - 0.5) < 1.5, "it stays near the block");
+	assert(take(1).some((m) => m.type === "move_entity" && m.id === item.id));
+
+	send(1, { type: "move", x: item.x, y: 100, z: item.z, yaw: 0, pitch: 0 });
+	game.tick();
+	const picked = take(1);
+	assert(picked.some((m) => m.type === "take_entity" && m.id === item.id));
+	assertEquals(inventory_count(picked, "bworld:dirt"), 1);
+	assertEquals(game.item_entities(), []);
+});
+
+Deno.test("items that don't fit in the inventory drop at the player's feet and stay there", async () => {
+	const { game, take, send, join } = await test_game("mods");
+	join(1, "alice");
+	build_floor(game);
+	send(1, { type: "move", x: 0.5, y: 100, z: 0.5, yaw: 0, pitch: 0 });
+
+	// a full inventory, then 10 more
+	send(1, { type: "chat", text: `/give bworld:stone ${64 * 36}` });
+	assertEquals(game.item_entities(), []);
+	send(1, { type: "chat", text: "/give bworld:stone 10" });
+	const [item] = game.item_entities();
+	assertEquals(item.item.amount, 10);
+
+	for (let i = 0; i < 60; i++) game.tick();
+	assertEquals(game.item_entities().length, 1, "a full inventory can't pick it up");
+	assert(take(1).some((m) => m.type === "add_entity"));
+});
+
+Deno.test("stacks next to each other merge, and items on the ground are saved with the world", async () => {
+	const { game, join } = await test_game("mods");
+	join(1, "alice");
+	build_floor(game);
+	for (let i = 0; i < 3; i++) {
+		game.spawn_item(6.5, 100, 0.5, new ItemStack("bworld:dirt", 2));
+	}
+	game.tick();
+	game.tick();
+	assertEquals(game.item_entities().map((entity) => entity.item.amount), [6]);
+
+	const saved = game.save();
+	const reloaded = await test_game("mods", saved);
+	assertEquals(reloaded.game.item_entities().map((entity) => [entity.item.type_id, entity.item.amount]), [[
+		"bworld:dirt",
+		6,
+	]]);
+	const joined = reloaded.join(2, "bob");
+	assertEquals(joined.entities.map((entity: { item: unknown }) => entity.item), [{ id: "bworld:dirt", count: 6 }]);
+});