2 files changed, 66 insertions, 0 deletions
diff --git a/graphs/js/jestBasic/fibo.js b/graphs/js/jestBasic/fibo.js
new file mode 100644
index 0000000..0a19955
--- /dev/null
+++ b/graphs/js/jestBasic/fibo.js
@@ -0,0 +1,29 @@
+function fibo(n) {
+    if (typeof n != "number" || isNaN(n)) {
+        return -1;
+    }
+
+    if (n < 0) {
+        return -1;
+    }
+
+    if (n === 0) {
+        return 0;
+    }
+
+    let a = 1;
+    let b = 1;
+    let result = 1;
+
+    for (let i = 2; i < n; i++) {
+        result = a + b;
+        b = a;
+        a = result;
+    }
+
+    return result;
+}
+
+module.exports = {
+    fibo,
+};
diff --git a/graphs/js/jestBasic/fibo.test.js b/graphs/js/jestBasic/fibo.test.js
new file mode 100644
index 0000000..6a97365
--- /dev/null
+++ b/graphs/js/jestBasic/fibo.test.js
@@ -0,0 +1,37 @@
+const { fibo } = require("./fibo");
+
+describe("basic value", () => {
+    test("fibo of 0", () => {
+        expect(fibo(0)).toBe(0);
+    });
+    test("fibo of 1", () => {
+        expect(fibo(1)).toBe(1);
+    });
+    test("fibo of 2", () => {
+        expect(fibo(2)).toBe(1);
+    });
+    test("fibo of 4", () => {
+        expect(fibo(4)).toBe(3);
+    });
+    test("fibo of 19", () => {
+        expect(fibo(19)).toBe(4181);
+    });
+});
+
+describe("errors", () => {
+    test("fibo of -1", () => {
+        expect(fibo(-1)).toBe(-1);
+    });
+    test("fibo of null", () => {
+        expect(fibo(null)).toBe(-1);
+    });
+    test("fibo of undefined", () => {
+        expect(fibo(undefined)).toBe(-1);
+    });
+    test("fibo of a string", () => {
+        expect(fibo("uwu adrien")).toBe(-1);
+    });
+    test("fibo of NaN", () => {
+        expect(fibo(NaN)).toBe(-1);
+    });
+});