feat: better handling of input validation for number

Author: Nicola Di Falco

spring-shell-core/src/main/java/org/springframework/shell/component/NumberInput.java

@@ -126,10 +126,14 @@ protected boolean read(BindingReader bindingReader, KeyMap<String> keyMap, Numbe
 				checkInput(input, context);
 				break;
 			case OPERATION_EXIT:
-				if (StringUtils.hasText(context.getInput())) {
+				var num = parseNumber(context.getInput());
+
+				if (num != null) {
 					context.setResultValue(parseNumber(context.getInput()));
-				}
-				else if (context.getDefaultValue() != null) {
+				} else if (StringUtils.hasText(context.getInput())) {
+					printInvalidInput(context.getInput(), context);
+					break;
+				} else if (context.getDefaultValue() != null) {
 					context.setResultValue(context.getDefaultValue());
 				} else if (required) {
 					context.setMessage("This field is mandatory", TextComponentContext.MessageLevel.ERROR);
@@ -161,14 +165,18 @@ private void checkInput(String input, NumberInputContext context) {
 		}
 		Number num =  parseNumber(input);
 		if (num == null) {
-			String msg = String.format("Sorry, your input is invalid: '%s', try again", input);
-			context.setMessage(msg, MessageLevel.ERROR);
+			printInvalidInput(input, context);
 		}
 		else {
 			context.setMessage(null);
 		}
 	}
 
+	private void printInvalidInput(String input, NumberInputContext context) {
+		String msg = String.format("Sorry, your input is invalid: '%s', try again", input);
+		context.setMessage(msg, MessageLevel.ERROR);
+	}
+
 	public interface NumberInputContext extends TextComponentContext<Number, NumberInputContext> {
 
 		/**

spring-shell-core/src/test/java/org/springframework/shell/component/NumberInputTests.java

@@ -238,12 +238,19 @@ public void testResultUserInputInvalidInput() throws InterruptedException, IOExc
 
 		latch1.await(2, TimeUnit.SECONDS);
 
+		NumberInputContext run1Context = result1.get();
 		assertThat(consoleOut()).contains("input is invalid");
+		assertThat(run1Context).isNull();
 
-		NumberInputContext run1Context = result1.get();
+		// backspace 2 : cr + input
+		testBuffer.backspace(2).append("2").cr();
+		write(testBuffer.getBytes());
 
+		latch1.await(2, TimeUnit.SECONDS);
+
+		run1Context = result1.get();
 		assertThat(run1Context).isNotNull();
-		assertThat(run1Context.getResultValue()).isNull();
+		assertThat(run1Context.getResultValue()).isEqualTo(2);
 	}
 
 	@Test