From cb87ae388da78f84ad6a6bc74376e9117a1e7fbf Mon Sep 17 00:00:00 2001
From: Derek Hamilton <Derek Hamilton>
Date: Mon, 25 Jan 2016 13:20:40 -0500
Subject: [PATCH] Return empty string when input is empty instead of 'Invalid
 Date' message.

---
 src/DateTimeField.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/DateTimeField.js b/src/DateTimeField.js
index 2e2d342b..93359eea 100644
--- a/src/DateTimeField.js
+++ b/src/DateTimeField.js
@@ -85,7 +85,8 @@ export default class DateTimeField extends Component {
 
   onChange = (event) => {
     const value = event.target == null ? event : event.target.value;
-    if (moment(value, this.state.inputFormat, true).isValid()) {
+    const isValueValid = moment(value, this.state.inputFormat, true).isValid();
+    if (isValueValid) {
       this.setState({
         selectedDate: moment(value, this.state.inputFormat, true),
         viewDate: moment(value, this.state.inputFormat, true).startOf("month")
@@ -95,7 +96,8 @@ export default class DateTimeField extends Component {
     return this.setState({
       inputValue: value
     }, function() {
-      return this.props.onChange(moment(this.state.inputValue, this.state.inputFormat, true).format(this.props.format), value);
+      const formattedValue = isValueValid ? moment(this.state.inputValue, this.state.inputFormat, true).format(this.props.format) : '';
+      return this.props.onChange(formattedValue, value);
     });
 
   }