Step 6: Implement Prop

src/prop/index.ts

@@ -0,0 +1,3 @@
+import Prop from "./prop";
+
+export default Prop;

src/prop/prop.spec.ts

@@ -0,0 +1,14 @@
+import { describe, it, expect } from "bun:test";
+import Prop from "./prop";
+
+describe("Prop", () => {
+  it("Has health", () => {
+    const p = new Prop({ health: 1000 });
+    expect(p.health).toBe(1000);
+  });
+
+  it("Has level 1", () => {
+    const p = new Prop();
+    expect(p.level).toBe(1);
+  });
+});

src/prop/prop.ts

@@ -0,0 +1,35 @@
+import Vec2d from "../utils/vec2d";
+import { AttackTarget } from "../actions";
+import { Neutral } from "../factions";
+
+interface PropOptions {
+  health?: number;
+  position?: Vec2d;
+}
+
+export default class Prop implements AttackTarget, Neutral {
+  #health: number;
+  readonly position: Vec2d;
+  readonly isNeutral = true;
+
+  constructor({ health = 1000, position = new Vec2d() }: PropOptions = {}) {
+    this.#health = health;
+    this.position = position;
+  }
+
+  get level() {
+    return 1;
+  }
+
+  get isAlive() {
+    return this.health > 0;
+  }
+
+  get health() {
+    return this.#health;
+  }
+
+  set health(value: number) {
+    this.#health = Math.max(0, value);
+  }
+}

test/combat.spec.ts

@@ -3,6 +3,7 @@ import { describe, it, expect } from "bun:test";
 import Character from "../src/character";
 import { AttackAction, HealAction, HealAnotherAction } from "../src/actions";
 import FactionManager from "../src/factions";
+import Prop from "../src/prop";
 
 describe("Character combat", () => {
   it("Allows characters to attack one another", () => {
@@ -60,3 +61,23 @@ describe("Factions", () => {
     }).toThrow(/invalid attack target/i);
   });
 });
+
+describe("Props", () => {
+  it("Cannot join factions", () => {
+    const house = new Prop();
+    const factions = new FactionManager();
+
+    expect(() => {
+      factions.join("foo", house);
+    }).toThrow(/invalid member/i);
+  });
+
+  it("Can be damaged by characters", () => {
+    const house = new Prop({ health: 1000 });
+    const attacker = new Character({ damage: 100 });
+
+    new AttackAction(attacker, house).run();
+
+    expect(house.health).toBe(900);
+  });
+});