Add testcases - utils.isConstructorFunctionComponent

test/utils.isConstructorFunctionComponent.spec.tsx

@@ -0,0 +1,74 @@
+// import * as React from "react";
+
+// Import stuff from src
+import { isConstructorFunctionComponent } from "../src/utils";
+import {
+  createFunctionComponent,
+  createClassComponent
+} from "./utils/createComponent";
+
+// Import test helpers and sample components
+
+describe("utils", () => {
+  let container: HTMLDivElement;
+
+  beforeEach(() => {
+    container = document.body.appendChild(document.createElement("div"));
+  });
+
+  afterEach(() => {
+    document.body.removeChild(container);
+  });
+
+  describe("isConstructorFunctionComponent", () => {
+    it("should work for any function - current limitation", () => {
+      const fn1 = function() {};
+
+      const resultPositive = isConstructorFunctionComponent(fn1 as any);
+
+      expect(resultPositive).not.toBeFalsy();
+      expect(resultPositive).toBe(true);
+    });
+
+    it("should work for function components", () => {
+      const fn1 = createFunctionComponent();
+
+      const resultPositive = isConstructorFunctionComponent(fn1);
+
+      expect(resultPositive).not.toBeFalsy();
+      expect(resultPositive).toBe(true);
+    });
+
+    it("should not work for string", () => {
+      const resultNegative = isConstructorFunctionComponent("div");
+
+      expect(resultNegative).toBeFalsy();
+      expect(resultNegative).toBe(false);
+    });
+
+    it("should not work for null", () => {
+      const resultNegative = isConstructorFunctionComponent(null);
+
+      expect(resultNegative).toBeFalsy();
+      expect(resultNegative).toBe(false);
+    });
+
+    it("should work for any class - current limitation", () => {
+      const C1 = class {};
+
+      const resultPositive = isConstructorFunctionComponent(C1 as any);
+
+      expect(resultPositive).not.toBeFalsy();
+      expect(resultPositive).toBe(true);
+    });
+
+    it("should not work for class components", () => {
+      const C1 = createClassComponent("C1");
+
+      const resultNegative = isConstructorFunctionComponent(C1);
+
+      expect(resultNegative).toBeFalsy();
+      expect(resultNegative).toBe(false);
+    });
+  });
+});