[added] optional custom function to compare input value to list option values

README.md

@@ -199,6 +199,19 @@ This is a shorthand for `wrapperProps={{ style: <your styles> }}`.
 Note that `wrapperStyle` is applied before `wrapperProps`, so the latter
 will win if it contains a `style` entry.
 
+#### `valueItemComparison: Function` (optional)
+Arguments: `optionItemValue: String, inputValue: String`
+Default value: 
+```jsx
+{
+  return (optionItemValue.toLowerCase().indexOf(
+        inputValue.toLowerCase()
+      ) === 0)
+}
+```
+
+The function which is used to compare the current input value to the currently highlighted item in the options list. Where by default the first item in the options list is compared to the input value. Returns a `Boolean`.
+
 
 ### Imperative API
 

lib/Autocomplete.js

@@ -147,6 +147,14 @@ class Autocomplete extends React.Component {
      * UX/business logic. Use it together with `onMenuVisibilityChange` for
      * fine-grained control over the dropdown menu dynamics.
      */
+    valueItemComparison: PropTypes.func,
+    /**
+     * Arguments: `optionItemValue: String, inputValue: String`
+     *
+     * Defines the function used to compare the current input value to the
+     * currently highlighted item in the options list. Where by default the
+     * first item in the options list is compared to the input value.
+     */
     open: PropTypes.bool,
     debug: PropTypes.bool,
   }
@@ -179,6 +187,11 @@ class Autocomplete extends React.Component {
     autoHighlight: true,
     selectOnBlur: false,
     onMenuVisibilityChange() {},
+    valueItemComparison(optionItemValue, inputValue) {
+      return (optionItemValue.toLowerCase().indexOf(
+        inputValue.toLowerCase()
+      ) === 0)
+    }
   }
 
   constructor(props) {
@@ -373,9 +386,7 @@ class Autocomplete extends React.Component {
     const matchedItem = this.getFilteredItems(props)[index]
     if (value !== '' && matchedItem) {
       const itemValue = getItemValue(matchedItem)
-      const itemValueDoesMatch = (itemValue.toLowerCase().indexOf(
-        value.toLowerCase()
-      ) === 0)
+      const itemValueDoesMatch = this.props.valueItemComparison(itemValue, value)
       if (itemValueDoesMatch) {
         return { highlightedIndex: index }
       }