test suite

Author: amoreaulemay

.gitignore

@@ -2,4 +2,5 @@
 .vscode/
 coverage/
 cov/
-lcov/
+lcov/
+cov_profile/

tests/mod.test.ts

@@ -0,0 +1,65 @@
+import { assertEquals, assertInstanceOf, assertNotEquals } from "https://deno.land/std@0.151.0/testing/asserts.ts";
+import * as mod from "../mod.ts";
+
+// Testing setup
+Deno.test("The StoreStack should be able to be instantiated", () => {
+    const Stores = new mod.StoreStack() as unknown;
+
+    assertInstanceOf(Stores, mod.StoreStack, "Stores should be instance of StoreStack");
+});
+
+Deno.test("window.stores should be of instance StoreStack when importing mod.ts", () => {
+    assertInstanceOf(window.stores as unknown, mod.StoreStack, "window.stores was expected to be instantiated");
+});
+
+// Testing creating a new store
+Deno.test("A new Store can be created", () => {
+    const state = "Test";
+    const store = new mod.Store(state);
+
+    assertInstanceOf(store, mod.Store, "store should be an instance of Store");
+    assertEquals(store.state, state, `store.state should be equal to "${state}"`);
+});
+
+Deno.test("A new observer can be created", () => {
+    class ConcreteObserver implements mod.Observer<void> {
+        public update(_subject: mod.Store<void>): void {
+            return;
+        }
+    }
+
+    const observer = new ConcreteObserver();
+
+    assertInstanceOf(observer, ConcreteObserver, "observer should be instance of ConcreteObserver");
+});
+
+Deno.test("A store can attach and trigger an observer", () => {
+    let ouput = "";
+    const expectedResult = "Test";
+
+    class ConcreteObserver implements mod.Observer<string> {
+        public update(subject: mod.Store<string>): void {
+            ouput = subject.state;
+        }
+    }
+
+    const store = new mod.Store(ouput);
+    store.attach(new ConcreteObserver());
+
+    assertEquals(store.state, ouput, "The ouput should equal the state");
+
+    store.set(expectedResult);
+
+    assertEquals(store.state, expectedResult, "The ouput should equal the expectedResult");
+});
+
+Deno.test("set can reuse a previous state to modify it", () => {
+    const ouput = 0;
+    const store = new mod.Store(ouput);
+
+    assertEquals(store.state, ouput, `The state should equal ${ouput}`);
+
+    store.set((prevState) => prevState + 1);
+
+    assertEquals(store.state, ouput + 1, "The state should increment by 1");
+});