Removed the caching in makeConfiguration and moved where it is invoked

This resolves a memory leak and gives greater performance overall

Author: dlmr

src/index.js

@@ -1,6 +1,7 @@
 import _ from 'lodash';
 import extendReactClass from './extendReactClass';
 import wrapStatelessFunction from './wrapStatelessFunction';
+import makeConfiguration from './makeConfiguration';
 
 /**
  * @see https://github.com/gajus/react-css-modules#options
@@ -20,10 +21,12 @@ const isReactComponent = (maybeReactComponent: any): boolean => {
 const functionConstructor = (Component: Function, defaultStyles: Object, options: OptionsType): Function => {
     let decoratedClass;
 
+    const configuration = makeConfiguration(options);
+
     if (isReactComponent(Component)) {
-        decoratedClass = extendReactClass(Component, defaultStyles, options);
+        decoratedClass = extendReactClass(Component, defaultStyles, configuration);
     } else {
-        decoratedClass = wrapStatelessFunction(Component, defaultStyles, options);
+        decoratedClass = wrapStatelessFunction(Component, defaultStyles, configuration);
     }
 
     if (Component.displayName) {

src/linkClass.js

@@ -2,7 +2,6 @@ import _ from 'lodash';
 import React, {
     ReactElement
 } from 'react';
-import makeConfiguration from './makeConfiguration';
 import isIterable from './isIterable';
 import parseStyleName from './parseStyleName';
 import generateAppendClassName from './generateAppendClassName';
@@ -61,15 +60,13 @@ const linkElement = (element: ReactElement, styles: Object, configuration: Objec
 /**
  * @param {ReactElement} element
  * @param {Object} styles CSS modules class map.
- * @param {CSSModules~Options} userConfiguration
+ * @param {CSSModules~Options} configuration
  */
-export default (element: ReactElement, styles = {}, userConfiguration): ReactElement => {
+export default (element: ReactElement, styles = {}, configuration = {}): ReactElement => {
     // @see https://github.com/gajus/react-css-modules/pull/30
     if (!_.isObject(element)) {
         return element;
     }
 
-    const configuration = makeConfiguration(userConfiguration);
-
     return linkElement(element, styles, configuration);
 };

src/makeConfiguration.js

@@ -1,7 +1,4 @@
 import _ from 'lodash';
-import Map from 'es6-map';
-
-const userConfigurationIndex = new Map();
 
 /**
  * @typedef CSSModules~Options
@@ -15,15 +12,7 @@ const userConfigurationIndex = new Map();
  * @returns {CSSModules~Options}
  */
 export default (userConfiguration = {}) => {
-    let configuration;
-
-    configuration = userConfigurationIndex.get(userConfiguration);
-
-    if (configuration) {
-        return configuration;
-    }
-
-    configuration = {
+    const configuration = {
         allowMultiple: false,
         errorWhenNotFound: true
     };
@@ -40,7 +29,5 @@ export default (userConfiguration = {}) => {
         configuration[name] = value;
     });
 
-    userConfigurationIndex.set(userConfiguration, configuration);
-
     return configuration;
 };