use deepEqual to test selectedValue and return null instead of undefi…

…ned in onChange when you unselect

package.json

@@ -81,6 +81,7 @@
   },
   "dependencies": {
     "debounce": "1.0.2",
+    "lodash.isequal": "4.5.0",
     "recompose": "0.25.0"
   },
   "lint-staged": {

src/core.js

@@ -1,5 +1,6 @@
 import React, {Component} from 'react'
 import PropTypes from 'prop-types'
+import isEqual from 'lodash.isequal'
 
 class SyncSelect extends Component {
   state = {
@@ -16,13 +17,14 @@ class SyncSelect extends Component {
   }
   componentWillUpdate(nextProps, nextState) {
     if (
-      nextState.selectedValue !== this.state.selectedValue &&
+      !isEqual(nextState.selectedValue, this.state.selectedValue) &&
       typeof this.props.onChange !== 'undefined' &&
       !nextProps.disabled
     ) {
-      this.props.onChange(
-        nextProps.multi ? nextState.selectedValue : nextState.selectedValue[0]
-      )
+      const val = nextProps.multi
+        ? nextState.selectedValue
+        : nextState.selectedValue[0]
+      this.props.onChange(typeof val === 'undefined' ? null : val)
     }
     if (nextProps.disabled && !this.props.disabled) {
       this.setState(() => ({opened: false}))

yarn.lock

@@ -4452,6 +4452,10 @@ lodash.isarray@^3.0.0:
   version "3.0.4"
   resolved "https://registry.yarnpkg.com/lodash.isarray/-/lodash.isarray-3.0.4.tgz#79e4eb88c36a8122af86f844aa9bcd851b5fbb55"
 
+[email protected]:
+  version "4.5.0"
+  resolved "https://registry.yarnpkg.com/lodash.isequal/-/lodash.isequal-4.5.0.tgz#415c4478f2bcc30120c22ce10ed3226f7d3e18e0"
+
 lodash.isnil@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/lodash.isnil/-/lodash.isnil-4.0.0.tgz#49e28cd559013458c814c5479d3c663a21bfaa6c"