test(sx tests): add tests for sx

Signed-off-by: Niloy Sikdar <niloysikdar30@gmail.com>

src/utils/index.ts

@@ -1,2 +1,2 @@
-export { sx } from './stylings';
+export { sx } from './sx';
 export { makeStyles } from './makeStyles';

src/utils/sx.test.ts

@@ -0,0 +1,26 @@
+import { CSSProperties } from 'react';
+import { sx } from './sx';
+
+const primary: CSSProperties = {
+  color: 'red',
+  backgroundColor: 'blue',
+};
+
+const button: CSSProperties = {
+  color: 'yellow',
+  borderRadius: '10px',
+};
+
+const expectedStyle: CSSProperties = {
+  color: 'yellow',
+  backgroundColor: 'blue',
+  borderRadius: '10px',
+};
+
+describe('sx tests', () => {
+  test('combining primary and button styles with sx should return expectedStyle', () => {
+    const style = sx(primary, button);
+
+    expect(style).toEqual(expectedStyle);
+  });
+});