tests: improving test coverage

__mocks__/react-copy-to-clipboard.jsx

@@ -0,0 +1,11 @@
+import React from "react";
+
+const CopyToClipboard = ({ children, onCopy, text }) => (
+    <div onClick={() => onCopy(text)} >
+        {children}
+    </div>
+);
+
+module.exports = {
+    CopyToClipboard
+};

package.json

@@ -14,6 +14,16 @@
     "start": "react-scripts start",
     "build": "react-scripts build",
     "test": "react-scripts test --env=jsdom",
-    "eject": "react-scripts eject"
+    "eject": "react-scripts eject",
+    "coverage": "yarn test -- --coverage"
+  },
+  "jest": {
+    "coverageReporters": [
+      "html",
+      "json",
+      "lcov",
+      "text",
+      "clover"
+    ]
   }
 }

src/components/converter.test.jsx

@@ -21,3 +21,23 @@ it('updates the state on the onChange event', () => {
 
   expect(converter.state.result).toBe(expectedValue);
 });
+
+it('should show "copied" text copy action', () => {
+  const converter = ReactTestUtils.renderIntoDocument(<Converter />);
+  const textarea = ReactTestUtils.findRenderedDOMComponentWithTag(converter, 'textarea');
+
+  jest.spyOn(converter, 'setCopiedToTrue');
+
+  const initialValue = '{ "a" : true }';
+  textarea.value = initialValue;
+  const expectedValue = jsonToGoMap(initialValue);
+
+  ReactTestUtils.Simulate.change(textarea);
+
+  expect(converter.setCopiedToTrue).not.toHaveBeenCalled();
+  const button = ReactTestUtils.findRenderedDOMComponentWithTag(converter, 'button');
+
+  ReactTestUtils.Simulate.click(button);
+
+  expect(converter.setCopiedToTrue).toHaveBeenCalledWith(expectedValue);
+});

src/lib/__snapshots__/jsonToGoMap.test.js.snap

@@ -19,7 +19,7 @@ exports[`the jsonToGoMap converter when a simple key/value object is given, it s
 }"
 `;
 
-exports[`the jsonToGoMap converter when array is given, it should return a interface list 1`] = `
+exports[`the jsonToGoMap converter when array is given, it should return an interface list 1`] = `
 "[]interface{}{
 	\\"A\\",
 	\\"B\\",

src/lib/jsonToGoMap.test.js

@@ -1,15 +1,15 @@
 import jsonToMap from "./jsonToGoMap";
 describe("the jsonToGoMap converter", () => {
-    test("when a empty string is given, it should return a empty result", () => {
+    test("when an empty value is given, it should return an empty string", () => {
         const result = jsonToMap("");
         expect(result).toEqual("");
     });
 
-    test("when a invalid JSON is given, it should return a error mensage", () => {
+    test("when an invalid JSON is given, it should return an error mensage", () => {
         const result = jsonToMap(`{"test": invalid`);
         expect(result).toEqual("Unexpected token i in JSON at position 9");
     });
-    
+
     test("when a simple key/value object is given, it should return a valid result", () => {
         const result = jsonToMap(`{"key": "value"}`);
         expect(result).toMatchSnapshot();
@@ -20,7 +20,7 @@ describe("the jsonToGoMap converter", () => {
         expect(result).toMatchSnapshot();
     });
 
-    test("when array is given, it should return a interface list", () => {
+    test("when array is given, it should return an interface list", () => {
         const result = jsonToMap(`["A", "B", 1]`);
         expect(result).toMatchSnapshot();
     });

src/pages/home.test.jsx

@@ -2,6 +2,8 @@ import React from 'react';
 import ReactDOM from 'react-dom';
 import Home from './home';
 
+jest.mock('react-copy-to-clipboard');
+
 it('renders without crashing', () => {
   const div = document.createElement('div');
   ReactDOM.render(<Home />, div);