feat(src/index): support synchronous config loading (rc.sync)

Author: bmatcuk

README.md

@@ -322,6 +322,8 @@ module.exports = (ctx) => ({
 }
 ```
 
+### `Async`
+
 ```js
 const { readFileSync } = require('fs')
 
@@ -339,6 +341,21 @@ postcssrc(ctx).then(({ plugins, options }) => {
 })
 ```
 
+### `Sync`
+
+```js
+const { readFileSync } = require('fs')
+
+const postcss = require('postcss')
+const postcssrc = require('postcss-load-config')
+
+const css = readFileSync('index.sss', 'utf8')
+
+const ctx = { parser: true, map: 'inline' }
+
+const { plugins, options } = postcssrc.sync(ctx)
+```
+
 <div align="center">
   <img width="80" height="80" halign="10" src="https://worldvectorlogo.com/logos/gulp.svg">
 </div>

src/index.js

@@ -8,17 +8,42 @@ const loadOptions = require('./options.js')
 const loadPlugins = require('./plugins.js')
 
 /**
- * Load Config
+ * Process the result from cosmiconfig
  *
- * @method rc
+ * @param  {Object} ctx Config Context
+ * @param  {Object} result Cosmiconfig result
+ *
+ * @return {Object} PostCSS Config
+ */
+const processResult = (ctx, result) => {
+  let file = result.filepath || ''
+  let config = result.config || {}
+
+  if (typeof config === 'function') {
+    config = config(ctx)
+  } else {
+    config = Object.assign({}, config, ctx)
+  }
+
+  if (!config.plugins) {
+    config.plugins = []
+  }
+
+  return {
+    plugins: loadPlugins(config, file),
+    options: loadOptions(config, file),
+    file: file
+  }
+}
+
+/**
+ * Builds the Config Context
  *
  * @param  {Object} ctx Config Context
- * @param  {String} path Config Path
- * @param  {Object} options Config Options
  *
- * @return {Promise} config PostCSS Config
+ * @return {Object} Config Context
  */
-const rc = (ctx, path, options) => {
+const createContext = (ctx) => {
   /**
    * @type {Object}
    *
@@ -29,24 +54,35 @@ const rc = (ctx, path, options) => {
     cwd: process.cwd(),
     env: process.env.NODE_ENV
   }, ctx)
+
+  if (!ctx.env) {
+    process.env.NODE_ENV = 'development'
+  }
+
+  return ctx
+}
+
+/**
+ * Load Config
+ *
+ * @method rc
+ *
+ * @param  {Object} ctx Config Context
+ * @param  {String} path Config Path
+ * @param  {Object} options Config Options
+ *
+ * @return {Promise} config PostCSS Config
+ */
+const rc = (ctx, path, options) => {
   /**
-   * @type {String} `process.cwd()`
-   *
+   * @type {Object} The full Config Context
    */
-  path = path ? resolve(path) : process.cwd()
+  ctx = createContext(ctx)
 
   /**
-   * @type {Object}
-   *
-   * @prop {Boolean} rcExtensions=true
+   * @type {String} `process.cwd()`
    */
-  options = Object.assign({
-    rcExtensions: true
-  }, options)
-
-  if (!ctx.env) {
-    process.env.NODE_ENV = 'development'
-  }
+  path = path ? resolve(path) : process.cwd()
 
   return config('postcss', options)
     .search(path)
@@ -55,25 +91,28 @@ const rc = (ctx, path, options) => {
         throw new Error(`No PostCSS Config found in: ${path}`)
       }
 
-      let file = result.filepath || ''
-      let config = result.config || {}
+      return processResult(ctx, result)
+    })
+}
 
-      if (typeof config === 'function') {
-        config = config(ctx)
-      } else {
-        config = Object.assign({}, config, ctx)
-      }
+rc.sync = (ctx, path, options) => {
+  /**
+   * @type {Object} The full Config Context
+   */
+  ctx = createContext(ctx)
 
-      if (!config.plugins) {
-        config.plugins = []
-      }
+  /**
+   * @type {String} `process.cwd()`
+   */
+  path = path ? resolve(path) : process.cwd()
 
-      return {
-        plugins: loadPlugins(config, file),
-        options: loadOptions(config, file),
-        file: file
-      }
-    })
+  const result = config('postcss', options).searchSync(path)
+
+  if (!result) {
+    throw new Error(`No PostCSS Config found in: ${path}`)
+  }
+
+  return processResult(ctx, result)
 }
 
 /**

src/plugins.js

@@ -14,22 +14,18 @@ const req = require('import-cwd')
  * @return {Function} PostCSS Plugin
  */
 const load = (plugin, options, file) => {
-  if (
-    options === null ||
-    options === undefined ||
-    Object.keys(options).length === 0
-  ) {
-    try {
+  try {
+    if (
+      options === null ||
+      options === undefined ||
+      Object.keys(options).length === 0
+    ) {
       return req(plugin)
-    } catch (err) {
-      throw new Error(`Loading PostCSS Plugin failed: ${err.message}\n\n(@${file})`)
-    }
-  } else {
-    try {
+    } else {
       return req(plugin)(options)
-    } catch (err) {
-      throw new Error(`Loading PostCSS Plugin failed: ${err.message}\n\n(@${file})`)
     }
+  } catch (err) {
+    throw new Error(`Loading PostCSS Plugin failed: ${err.message}\n\n(@${file})`)
   }
 }
 

test/Errors.test.js

@@ -10,6 +10,16 @@ test('Loading Config - {Error}', () => {
   })
 })
 
+test('Loading Config - Sync - {Error}', () => {
+  try {
+    postcssrc.sync({}, 'test/err')
+  } catch (err) {
+    expect(err.message).toMatch(
+      /^No PostCSS Config found in: (.*)$/
+    )
+  }
+})
+
 describe('Loading Plugins - {Error}', () => {
   test('Plugin - {Type} - Invalid', () => {
     return postcssrc({}, 'test/err/plugins').catch((err) => {
@@ -52,6 +62,58 @@ describe('Loading Plugins - {Error}', () => {
   })
 })
 
+describe('Loading Plugins - Sync - {Error}', () => {
+  test('Plugin - {Type} - Invalid', () => {
+    try {
+      postcssrc.sync({}, 'test/err/plugins')
+    } catch (err) {
+      expect(err.message).toMatch(
+        /^Invalid PostCSS Plugin found at: (.*)\n\n\(@.*\)$/
+      )
+    }
+  })
+
+  test('Plugin - {Object}', () => {
+    try {
+      postcssrc.sync({}, 'test/err/plugins/object')
+    } catch (err) {
+      expect(err.message).toMatch(
+        /^Loading PostCSS Plugin failed: (.*)\n\n\(@.*\)$/
+      )
+    }
+  })
+
+  test('Plugin - {Object} - Options', () => {
+    try {
+      postcssrc.sync({}, 'test/err/plugins/object/options')
+    } catch (err) {
+      expect(err.message).toMatch(
+        /^Loading PostCSS Plugin failed: (.*)\n\n\(@.*\)$/
+      )
+    }
+  })
+
+  test('Plugin - {Array}', () => {
+    try {
+      postcssrc.sync({}, 'test/err/plugins/array')
+    } catch (err) {
+      expect(err.message).toMatch(
+        /^Cannot find (.*)$/
+      )
+    }
+  })
+
+  test('Plugin - {Array} - Options', () => {
+    try {
+      postcssrc.sync({}, 'test/err/plugins/array/options')
+    } catch (err) {
+      expect(err.message).toMatch(
+        /^Cannot find (.*)$/
+      )
+    }
+  })
+})
+
 describe('Loading Options - {Error}', () => {
   test('Parser - {String}', () => {
     return postcssrc({}, 'test/err/options/parser').catch((err) => {
@@ -77,3 +139,35 @@ describe('Loading Options - {Error}', () => {
     })
   })
 })
+
+describe('Loading Options - Sync - {Error}', () => {
+  test('Parser - {String}', () => {
+    try {
+      postcssrc.sync({}, 'test/err/options/parser')
+    } catch (err) {
+      expect(err.message).toMatch(
+        /^Loading PostCSS Parser failed: (.*)\n\n\(@.*\)$/
+      )
+    }
+  })
+
+  test('Syntax - {String}', () => {
+    try {
+      postcssrc.sync({}, 'test/err/options/syntax')
+    } catch (err) {
+      expect(err.message).toMatch(
+        /^Loading PostCSS Syntax failed: (.*)\n\n\(@.*\)$/
+      )
+    }
+  })
+
+  test('Stringifier - {String}', () => {
+    try {
+      postcssrc.sync({}, 'test/err/options/stringifier')
+    } catch (err) {
+      expect(err.message).toMatch(
+        /^Loading PostCSS Stringifier failed: (.*)\n\n\(@.*\)$/
+      )
+    }
+  })
+})

test/js.test.js

@@ -7,13 +7,13 @@ const postcssrc = require('../src/index.js')
 
 const { fixture, expected } = require('./utils.js')
 
-test('postcss.config.js - {Object} - Load Config', () => {
+describe('postcss.config.js - {Object} - Load Config', () => {
   const ctx = {
     parser: true,
     syntax: true
   }
 
-  return postcssrc(ctx, 'test/js/object').then((config) => {
+  const expected = (config) => {
     expect(config.options.parser).toEqual(require('sugarss'))
     expect(config.options.syntax).toEqual(require('sugarss'))
     expect(config.options.map).toEqual(false)
@@ -26,6 +26,16 @@ test('postcss.config.js - {Object} - Load Config', () => {
 
     expect(config.file)
       .toEqual(path.resolve('test/js/object', 'postcss.config.js'))
+  }
+
+  test('Async', () => {
+    return postcssrc(ctx, 'test/js/object').then(expected)
+  })
+
+  test('Sync', () => {
+    const config = postcssrc.sync(ctx, 'test/js/object')
+
+    expected(config)
   })
 })
 
@@ -60,13 +70,13 @@ test('postcss.config.js - {Object} - Process SSS', () => {
   })
 })
 
-test('postcss.config.js - {Array} - Load Config', () => {
+describe('postcss.config.js - {Array} - Load Config', () => {
   const ctx = {
     parser: true,
     syntax: true
   }
 
-  return postcssrc(ctx, 'test/js/array').then((config) => {
+  const expected = (config) => {
     expect(config.options.parser).toEqual(require('sugarss'))
     expect(config.options.syntax).toEqual(require('sugarss'))
     expect(config.options.map).toEqual(false)
@@ -79,6 +89,16 @@ test('postcss.config.js - {Array} - Load Config', () => {
 
     expect(config.file)
       .toEqual(path.resolve('test/js/array', 'postcss.config.js'))
+  }
+
+  test('Async', () => {
+    return postcssrc(ctx, 'test/js/array').then(expected)
+  })
+
+  test('Sync', () => {
+    const config = postcssrc.sync(ctx, 'test/js/array')
+
+    expected(config)
   })
 })