Merge pull request JedWatson#1858 from not-an-aardvark/no-mutate-input-value

Avoid mutating user input when ignoring case/accents (fixes JedWatson#1352)

Author: agirton

src/Async.js

@@ -131,26 +131,28 @@ export default class Async extends Component {
 				isLoading: true
 			});
 		}
-
-		return inputValue;
 	}
 
 	_onInputChange (inputValue) {
 		const { ignoreAccents, ignoreCase, onInputChange } = this.props;
+		let transformedInputValue = inputValue;
 
 		if (ignoreAccents) {
-			inputValue = stripDiacritics(inputValue);
+			transformedInputValue = stripDiacritics(transformedInputValue);
 		}
 
 		if (ignoreCase) {
-			inputValue = inputValue.toLowerCase();
+			transformedInputValue = transformedInputValue.toLowerCase();
 		}
 
 		if (onInputChange) {
-			onInputChange(inputValue);
+			onInputChange(transformedInputValue);
 		}
 
-		return this.loadOptions(inputValue);
+		this.loadOptions(transformedInputValue);
+
+		// Return the original input value to avoid modifying the user's view of the input while typing.
+		return inputValue;
 	}
 
 	inputValue() {

test/Async-test.js

@@ -319,6 +319,15 @@ describe('Async', () => {
 			typeSearchText('WÄRE');
 			expect(loadOptions, 'was called with', 'WÄRE');
 		});
+
+		it('does not mutate the user input', () => {
+			createControl({
+				ignoreAccents: false,
+				ignoreCase: true
+			});
+			typeSearchText('A');
+			expect(asyncNode.textContent, 'to begin with', 'A');
+		});
 	});
 
 	describe('with ignore case and ignore accents', () => {