Fix error message formatting when using the bean validation API with command options

Resolves #1100

Author: fmbenhassine

spring-shell-core/src/main/java/org/springframework/shell/result/ParameterValidationExceptionResultHandler.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2022 the original author or authors.
+ * Copyright 2017-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,6 +15,8 @@
  */
 package org.springframework.shell.result;
 
+import jakarta.validation.Path;
+
 import org.jline.terminal.Terminal;
 import org.jline.utils.AttributedString;
 import org.jline.utils.AttributedStyle;
@@ -26,6 +28,7 @@
  *
  * @author Eric Bottard
  * @author Janne Valkealahti
+ * @author Mahmoud Ben Hassine
  */
 public class ParameterValidationExceptionResultHandler
 		extends TerminalAwareResultHandler<ParameterValidationException> {
@@ -39,10 +42,19 @@ protected void doHandleResult(ParameterValidationException result) {
 		terminal.writer().println(new AttributedString("The following constraints were not met:",
 				AttributedStyle.DEFAULT.foreground(AttributedStyle.RED)).toAnsi());
 		result.getConstraintViolations().stream()
-				.forEach(v -> {
-					terminal.writer().println(new AttributedString(v.toString(),
+				.forEach(violation -> {
+					Path propertyPath = violation.getPropertyPath();
+					String violationMessage = violation.getMessage();
+					String errorMessage = String.format("\t--%s: %s", extractPropertyName(propertyPath), violationMessage);
+					terminal.writer().println(new AttributedString(errorMessage,
 						AttributedStyle.DEFAULT.foreground(AttributedStyle.RED)).toAnsi(terminal));
 				});
 	}
 
+	private String extractPropertyName(Path propertyPath) {
+		String path = propertyPath.toString();
+		int lastIndexOfDot = path.lastIndexOf(".");
+		return lastIndexOfDot == -1 ? path : path.substring(lastIndexOfDot + 1);
+	}
+
 }

spring-shell-docs/modules/ROOT/pages/options/validation.adoc

@@ -20,5 +20,5 @@ From the preceding example, you get the following behavior for free:
 ----
 shell:>change-password hello
 The following constraints were not met:
-	--password string : size must be between 8 and 40 (You passed 'hello')
+	--password : size must be between 8 and 40 (You passed 'hello')
 ----