/** * Test suite for the classnames utility function * This utility combines the classnames library with tailwind-merge * to handle conditional CSS classes and merge conflicting Tailwind classes */ import cn from './classnames' describe('classnames', () => { /** * Tests basic classnames library features: * - String concatenation * - Array handling * - Falsy value filtering * - Object-based conditional classes */ test('classnames libs feature', () => { expect(cn('foo')).toBe('foo') expect(cn('foo', 'bar')).toBe('foo bar') expect(cn(['foo', 'bar'])).toBe('foo bar') expect(cn(undefined)).toBe('') expect(cn(null)).toBe('') expect(cn(false)).toBe('') expect(cn({ foo: true, bar: false, baz: true, })).toBe('foo baz') }) /** * Tests tailwind-merge functionality: * - Conflicting class resolution (last one wins) * - Modifier handling (hover, focus, etc.) * - Important prefix (!) * - Custom color classes * - Arbitrary values */ test('tailwind-merge', () => { /* eslint-disable tailwindcss/classnames-order */ expect(cn('p-0')).toBe('p-0') expect(cn('text-right text-center text-left')).toBe('text-left') expect(cn('pl-4 p-8')).toBe('p-8') expect(cn('m-[2px] m-[4px]')).toBe('m-[4px]') expect(cn('m-1 m-[4px]')).toBe('m-[4px]') expect(cn('overflow-x-auto hover:overflow-x-hidden overflow-x-scroll')).toBe( 'hover:overflow-x-hidden overflow-x-scroll', ) expect(cn('h-10 h-min')).toBe('h-min') expect(cn('bg-grey-5 bg-hotpink')).toBe('bg-hotpink') expect(cn('hover:block hover:inline')).toBe('hover:inline') expect(cn('font-medium !font-bold')).toBe('font-medium !font-bold') expect(cn('!font-medium !font-bold')).toBe('!font-bold') expect(cn('text-gray-100 text-primary-200')).toBe('text-primary-200') expect(cn('text-some-unknown-color text-components-input-bg-disabled text-primary-200')).toBe('text-primary-200') expect(cn('bg-some-unknown-color bg-components-input-bg-disabled bg-primary-200')).toBe('bg-primary-200') expect(cn('border-t border-white/10')).toBe('border-t border-white/10') expect(cn('border-t border-white')).toBe('border-t border-white') expect(cn('text-3.5xl text-black')).toBe('text-3.5xl text-black') }) /** * Tests the integration of classnames and tailwind-merge: * - Object-based conditional classes with Tailwind conflict resolution */ test('classnames combined with tailwind-merge', () => { expect(cn('text-right', { 'text-center': true, })).toBe('text-center') expect(cn('text-right', { 'text-center': false, })).toBe('text-right') }) /** * Tests handling of multiple mixed argument types: * - Strings, arrays, and objects in a single call * - Tailwind merge working across different argument types */ test('multiple mixed argument types', () => { expect(cn('foo', ['bar', 'baz'], { qux: true, quux: false })).toBe('foo bar baz qux') expect(cn('p-4', ['p-2', 'm-4'], { 'text-left': true, 'text-right': true })).toBe('p-2 m-4 text-right') }) /** * Tests nested array handling: * - Deep array flattening * - Tailwind merge with nested structures */ test('nested arrays', () => { expect(cn(['foo', ['bar', 'baz']])).toBe('foo bar baz') expect(cn(['p-4', ['p-2', 'text-center']])).toBe('p-2 text-center') }) /** * Tests empty input handling: * - Empty strings, arrays, and objects * - Mixed empty and non-empty values */ test('empty inputs', () => { expect(cn('')).toBe('') expect(cn([])).toBe('') expect(cn({})).toBe('') expect(cn('', [], {})).toBe('') expect(cn('foo', '', 'bar')).toBe('foo bar') }) /** * Tests number input handling: * - Truthy numbers converted to strings * - Zero treated as falsy */ test('numbers as inputs', () => { expect(cn(1)).toBe('1') expect(cn(0)).toBe('') expect(cn('foo', 1, 'bar')).toBe('foo 1 bar') }) /** * Tests multiple object arguments: * - Object merging * - Tailwind conflict resolution across objects */ test('multiple objects', () => { expect(cn({ foo: true }, { bar: true })).toBe('foo bar') expect(cn({ foo: true, bar: false }, { bar: true, baz: true })).toBe('foo bar baz') expect(cn({ 'p-4': true }, { 'p-2': true })).toBe('p-2') }) /** * Tests complex edge cases: * - Mixed falsy values * - Nested arrays with falsy values * - Multiple conflicting Tailwind classes */ test('complex edge cases', () => { expect(cn('foo', null, undefined, false, 'bar', 0, 1, '')).toBe('foo bar 1') expect(cn(['foo', null, ['bar', undefined, 'baz']])).toBe('foo bar baz') expect(cn('text-sm', { 'text-lg': false, 'text-xl': true }, 'text-2xl')).toBe('text-2xl') }) /** * Tests important (!) modifier behavior: * - Important modifiers in objects * - Conflict resolution with important prefix */ test('important modifier with objects', () => { expect(cn({ '!font-medium': true }, { '!font-bold': true })).toBe('!font-bold') expect(cn('font-normal', { '!font-bold': true })).toBe('font-normal !font-bold') }) })