test: add unit tests for the module (#892)

Co-authored-by: Benjamin Canac <canacb1@gmail.com>

test/basic.spec.ts

@@ -0,0 +1,123 @@
+import { describe, expect, it } from 'vitest'
+import module from '../src/module'
+import { loadNuxt } from '@nuxt/kit'
+import { join } from 'path'
+
+// TODO: fix these anys
+async function getTailwindCSSConfig (overrides: any = {}): Promise<[any, any]> {
+  overrides.modules = [ module ]
+  overrides.ssr = overrides.ssr ?? false
+  overrides.hooks = overrides.hooks ?? {}
+  return new Promise((resolve) => {
+    overrides.hooks['tailwindcss:resolvedConfig'] = async (config) => {
+        resolve([config, nuxt])
+      }
+    const nuxt = loadNuxt({
+      cwd: join(process.cwd(), 'fixtures', 'empty'),
+      dev: false,
+      overrides
+    })
+  })
+}
+
+describe('nuxt', () => {
+  it('should add plugins and modules to nuxt', async () => {
+    const [, lnuxt] = await getTailwindCSSConfig()
+    await lnuxt.then((nuxt) => {
+      expect(nuxt.options.plugins).toContainEqual(
+        expect.objectContaining({
+          src: expect.stringContaining('plugins/colors'),
+          mode: 'all'
+        })
+      )
+      expect(nuxt.options._requiredModules).toContain({
+        '@nuxtjs/color-mode': true,
+        '@nuxtjs/tailwindcss': true
+      })
+      // default values in appConfig
+      expect(nuxt.options.appConfig.ui).toContain({
+        primary: 'green',
+        gray: 'cool'
+      })
+      // TODO: this should be done inside getTailwindCSSConfig
+      nuxt.close()
+    })
+  })
+})
+
+describe('tailwindcss config', () => {
+  it.each([
+    /* format:
+     name,
+     tailwindcss config, safelistColors,
+     expected safelistPatterns (add "!" before a pattern to negate it)
+    */
+    [
+      'default safelist',
+      {}, [],
+      ['bg-(primary)-50', 'bg-(red)-500'] // these both should be in the safelist
+    ],
+    [
+      'safelisting single new color',
+      {}, ['myColor'],
+      'bg-(myColor|primary)-50'
+    ],
+    [
+      'reducing amount of theme colors',
+      { theme: { colors: { plainBlue: '#00F' } } }, ['plainBlue'],
+      ['bg-(plainBlue|primary)-50', '!', /orange/] // the word "orange" should _not_ be found in any safelist pattern
+    ]
+  ])('%s', async (_description, tailwindcss, safelistColors, safelistPatterns) => {
+    const [config, _nuxt] = await getTailwindCSSConfig({
+      ui: {
+        safelistColors
+      },
+      tailwindcss: {
+        config: tailwindcss
+      }
+    })
+    expect.extend({
+      toBeRegExp: (received, expected) => {
+        if (typeof expected === 'string' || expected instanceof String) {
+          return {
+            message: () => `expected ${received} to be exact regex ${expected}`,
+            pass: received.toString() === RegExp(expected as string).toString()
+          }
+        } else if (expected instanceof RegExp) {
+          return {
+            message: () => `expected ${received} to be a regex like ${expected.toString()}`,
+            pass: received.toString().match(expected)
+          }
+        }
+        return {
+          message: () => `expected ${received} to be a regex`,
+          pass: false
+        }
+      }
+    })
+    safelistPatterns = safelistPatterns instanceof Array ? safelistPatterns : [safelistPatterns]
+
+    let negate = false
+    for (const safelistPattern of safelistPatterns) {
+      if (safelistPattern === '!') {
+        // negate next!
+        negate = true
+        continue
+      }
+      if (negate) {
+        expect(config.safelist).not.toContainEqual({
+          pattern: expect.toBeRegExp(safelistPattern)
+        })
+      } else {
+        expect(config.safelist).toContainEqual({
+          pattern: expect.toBeRegExp(safelistPattern)
+        })
+      }
+      negate = false
+    }
+
+    await _nuxt.then((n) => {
+      n.close()
+    })
+  })
+})