Allow plugins to provide their own config object

__tests__/resolveConfig.test.js

@@ -1359,15 +1359,13 @@ test('more than two config objects can be resolved', () => {
     },
   })
 })
+
 test('plugin config modifications are applied', () => {
   const userConfig = {
     plugins: [
       {
-        modifyConfig(config) {
-          return {
-            ...config,
-            prefix: 'tw-',
-          }
+        config: {
+          prefix: 'tw-',
         },
         handler() {},
       },
@@ -1415,11 +1413,8 @@ test('user config takes precedence over plugin config modifications', () => {
     prefix: 'user-',
     plugins: [
       {
-        modifyConfig(config) {
-          return {
-            ...config,
-            prefix: 'plugin-',
-          }
+        config: {
+          prefix: 'tw-',
         },
         handler() {},
       },
@@ -1461,3 +1456,121 @@ test('user config takes precedence over plugin config modifications', () => {
     plugins: userConfig.plugins,
   })
 })
+
+test('plugin config can register plugins that also have config', () => {
+  const userConfig = {
+    plugins: [
+      {
+        config: {
+          prefix: 'tw-',
+          plugins: [
+            {
+              config: {
+                important: true,
+              },
+              handler() {}
+            },
+            {
+              config: {
+                separator: '__',
+              },
+              handler() {}
+            },
+          ]
+        },
+        handler() {},
+      },
+    ],
+  }
+
+  const defaultConfig = {
+    prefix: '',
+    important: false,
+    separator: ':',
+    theme: {
+      screens: {
+        mobile: '400px',
+      },
+    },
+    variants: {
+      appearance: ['responsive'],
+      borderCollapse: [],
+      borderColors: ['responsive', 'hover', 'focus'],
+    },
+  }
+
+  const result = resolveConfig([userConfig, defaultConfig])
+
+  expect(result).toEqual({
+    prefix: 'tw-',
+    important: true,
+    separator: '__',
+    theme: {
+      screens: {
+        mobile: '400px',
+      },
+    },
+    variants: {
+      appearance: ['responsive'],
+      borderCollapse: [],
+      borderColors: ['responsive', 'hover', 'focus'],
+    },
+    plugins: userConfig.plugins,
+  })
+})
+
+test('plugin configs take precedence over plugin configs registered by that plugin', () => {
+  const userConfig = {
+    plugins: [
+      {
+        config: {
+          prefix: 'outer-',
+          plugins: [
+            {
+              config: {
+                prefix: 'inner-',
+              },
+              handler() {}
+            }
+          ]
+        },
+        handler() {},
+      },
+    ],
+  }
+
+  const defaultConfig = {
+    prefix: '',
+    important: false,
+    separator: ':',
+    theme: {
+      screens: {
+        mobile: '400px',
+      },
+    },
+    variants: {
+      appearance: ['responsive'],
+      borderCollapse: [],
+      borderColors: ['responsive', 'hover', 'focus'],
+    },
+  }
+
+  const result = resolveConfig([userConfig, defaultConfig])
+
+  expect(result).toEqual({
+    prefix: 'outer-',
+    important: false,
+    separator: ':',
+    theme: {
+      screens: {
+        mobile: '400px',
+      },
+    },
+    variants: {
+      appearance: ['responsive'],
+      borderCollapse: [],
+      borderColors: ['responsive', 'hover', 'focus'],
+    },
+    plugins: userConfig.plugins,
+  })
+})

src/index.js

@@ -56,7 +56,7 @@ const getConfigFunction = config => () => {
   }
 
   const configObject = _.isObject(config) ? _.get(config, 'config', config) : require(config)
-
+  
   return resolveConfig([configObject, defaultConfig])
 }
 

src/util/resolveConfig.js

@@ -1,10 +1,9 @@
 import some from 'lodash/some'
 import mergeWith from 'lodash/mergeWith'
+import isEmpty from 'lodash/isEmpty'
 import isFunction from 'lodash/isFunction'
 import isUndefined from 'lodash/isUndefined'
 import defaults from 'lodash/defaults'
-import identity from 'lodash/identity'
-import get from 'lodash/get'
 import map from 'lodash/map'
 import get from 'lodash/get'
 import toPath from 'lodash/toPath'
@@ -24,12 +23,6 @@ const configUtils = {
   },
 }
 
-function applyPluginConfigModifications(config, plugins) {
-  return plugins.reduce((modified, plugin) => {
-    return get(plugin, 'modifyConfig', identity)(modified)
-  }, config)
-}
-
 function value(valueToResolve, ...args) {
   return isFunction(valueToResolve) ? valueToResolve(...args) : valueToResolve
 }
@@ -102,25 +95,41 @@ function resolveFunctionKeys(object) {
   }, {})
 }
 
-export default function resolveConfig([userConfig, defaultConfig]) {
-  const modifiedDefaultConfig = applyPluginConfigModifications(
-    defaultConfig,
-    get(userConfig, 'plugins', [])
-  )
-  const configs = [userConfig, modifiedDefaultConfig]
+function extractPluginConfigs(configs) {
+  let allConfigs = []
+
+  configs.forEach(config => {
+    allConfigs = [...allConfigs, config]
+
+    const plugins = get(config, 'plugins', [])
+    
+    if (plugins.length === 0) {
+      return
+    }
+
+    plugins.forEach(plugin => {
+      allConfigs = [...allConfigs, ...extractPluginConfigs([get(plugin, 'config', {})])]
+    })
+  })
+
+  return allConfigs
+}
+
+export default function resolveConfig(configs) {
+  const allConfigs = extractPluginConfigs(configs)
 
   return defaults(
     {
       // Need to get a default empty object if the config has no theme
       theme: resolveFunctionKeys(
-        mergeExtensions(mergeThemes(map(configs, t => get(t, 'theme', {}))))
+        mergeExtensions(mergeThemes(map(allConfigs, t => get(t, 'theme', {}))))
       ),
       variants: (firstVariants => {
         return Array.isArray(firstVariants)
           ? firstVariants
-          : defaults({}, ...map(configs, 'variants'))
-      })(defaults({}, ...map(configs)).variants),
+          : defaults({}, ...map(allConfigs, 'variants'))
+      })(defaults({}, ...map(allConfigs)).variants),
     },
-    ...configs
+    ...allConfigs
   )
 }