add icon and theme tests

src/test/components/__snapshots__/icon.spec.tsx.snap

@@ -1,5 +1,7 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`Icon test (no size) 1`] = `[Function]`;
+
 exports[`Icon test 1`] = `[Function]`;
 
 exports[`IconButton test 1`] = `[Function]`;

src/test/components/icon.spec.tsx

@@ -12,6 +12,11 @@ it("Icon test", () => {
   expect(asFragment).toMatchSnapshot();
 });
 
+it("Icon test (no size)", () => {
+  const { asFragment } = render(<Icon name={props.name} />);
+  expect(asFragment).toMatchSnapshot();
+});
+
 it("IconButton test", () => {
   const { asFragment } = render(
     <IconButton icon={props.name} onClick={props.onClick} />,

src/test/lib/theme.spec.tsx

@@ -0,0 +1,44 @@
+import selectedTheme, {
+  getTheme,
+  IThemeProps,
+  setTheme,
+} from "../../lib/theme";
+
+const props: IThemeProps = {
+  label: "Classic",
+  value: 0,
+  mainColor: "#000000",
+  accentColor: "#1e272e",
+  backgroundColor: "#ffffff",
+};
+
+const theme = JSON.stringify(props);
+
+describe("theme.tsx", () => {
+  beforeEach(() => {
+    Object.defineProperty(window, "localStorage", {
+      value: {
+        getItem: jest.fn(() => null),
+        setItem: jest.fn(() => null),
+      },
+      writable: true,
+    });
+  });
+
+  it("setTheme test", () => {
+    setTheme(theme);
+
+    expect(window.localStorage.setItem).toHaveBeenCalledTimes(1);
+    expect(window.localStorage.setItem).toHaveBeenCalledWith("theme", theme);
+  });
+
+  it("getTheme test", () => {
+    const themeTest = getTheme();
+    expect(themeTest).toEqual(props);
+  });
+
+  it("selectedTheme test", () => {
+    const themeTest = selectedTheme;
+    expect(themeTest).toEqual(props);
+  });
+});