Test plugins can add base styles with object syntax

__tests__/processPlugins.test.js

@@ -254,6 +254,33 @@ test('plugins can create components with object syntax', () => {
     `)
 })
 
+test('plugins can add base styles with object syntax', () => {
+  const { base } = processPlugins(
+    [
+      function({ addBase }) {
+        addBase({
+          'img': {
+            maxWidth: '100%',
+          },
+          'button': {
+            fontFamily: 'inherit',
+          },
+        })
+      },
+    ],
+    makeConfig()
+  )
+
+  expect(css(base)).toMatchCss(`
+    img {
+      max-width: 100%
+    }
+    button {
+      font-family: inherit
+    }
+    `)
+})
+
 test('plugins can create components with raw PostCSS nodes', () => {
   const { components, utilities } = processPlugins(
     [

src/util/processPlugins.js

@@ -16,6 +16,7 @@ function parseStyles(styles) {
 }
 
 export default function(plugins, config) {
+  const pluginBaseStyles = []
   const pluginComponents = []
   const pluginUtilities = []
   const pluginVariantGenerators = {}
@@ -63,6 +64,9 @@ export default function(plugins, config) {
 
         pluginComponents.push(...styles.nodes)
       },
+      addBase: (baseStyles) => {
+        pluginBaseStyles.push(...parseStyles(baseStyles))
+      },
       addVariant: (name, generator) => {
         pluginVariantGenerators[name] = generateVariantFunction(generator)
       },
@@ -70,6 +74,7 @@ export default function(plugins, config) {
   })
 
   return {
+    base: pluginBaseStyles,
     components: pluginComponents,
     utilities: pluginUtilities,
     variantGenerators: pluginVariantGenerators,