From 852a76ef717f9a989cf82a6ef82645844bb185d6 Mon Sep 17 00:00:00 2001
From: James Donnelly <4444684+JDIZM@users.noreply.github.com>
Date: Mon, 29 Jan 2024 09:26:20 +0000
Subject: [PATCH] test: mortgage calculator unit tests

---
 calc/mortgageCalculator.test.ts | 50 +++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 calc/mortgageCalculator.test.ts

diff --git a/calc/mortgageCalculator.test.ts b/calc/mortgageCalculator.test.ts
new file mode 100644
index 0000000..e854565
--- /dev/null
+++ b/calc/mortgageCalculator.test.ts
@@ -0,0 +1,50 @@
+import { describe, expect, it } from "vitest";
+import { mortgageCalculator } from "./mortgageCalculator";
+
+describe("mortgageCalculator", () => {
+  it("should calculate an interest only mortgage with the correct payments and pricipal", () => {
+    const result = mortgageCalculator(
+      {
+        homeValue: 150_000,
+        deposit: 15_000,
+        interestRate: 6,
+        years: 25
+      },
+      "interestOnly"
+    );
+
+    expect(result).toMatchObject({
+      homeValue: 150000,
+      deposit: 15000,
+      interestPayments: {
+        yearly: 8100,
+        monthly: 675,
+        period: 675
+      },
+      principal: 135000,
+      years: 25,
+      interestRate: 6
+    });
+  });
+
+  it("should calculate a repayment mortgage with the correct monthly payment and remaining principal rounded to two decimal places", () => {
+    const result = mortgageCalculator(
+      {
+        homeValue: 150_000,
+        deposit: 15_000,
+        interestRate: 6,
+        years: 25
+      },
+      "repayment"
+    );
+
+    expect(result).toMatchObject({
+      deposit: 15000,
+      homeValue: 150000,
+      interestRate: 6,
+      monthlyRepayment: 869.81,
+      principal: 135000,
+      years: 25
+    });
+  });
+});