Fix error message when introspection is missing and method has generi…

…c signature (#443)

Fixed #417

test-suite/src/test/java/io/micronaut/docs/validation/PojoOptionalGetterSpec.java

@@ -6,13 +6,12 @@
 import jakarta.inject.Singleton;
 import jakarta.validation.Valid;
 import org.junit.jupiter.api.Test;
-import spock.lang.Specification;
 
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 
 @Property(name = "spec.name", value = "PojoOptionalGetterSpec")
 @MicronautTest
-class PojoOptionalGetterTest extends Specification {
+class PojoOptionalGetterSpec {
 
     @Test
     void pojoCanHaveGetterWhichReturnsAnOptional(MockService service) {

test-suite/src/test/java/io/micronaut/docs/validation/WrongValidationTest.java

@@ -0,0 +1,48 @@
+package io.micronaut.docs.validation;
+
+import io.micronaut.context.annotation.Property;
+import io.micronaut.context.annotation.Requires;
+import io.micronaut.core.annotation.Introspected;
+import io.micronaut.test.extensions.junit5.annotation.MicronautTest;
+import io.micronaut.validation.Validated;
+import jakarta.inject.Inject;
+import jakarta.inject.Singleton;
+import jakarta.validation.ConstraintViolationException;
+import jakarta.validation.Valid;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+@Property(name = "spec.name", value = "WrongValidationTest")
+@MicronautTest
+class WrongValidationTest {
+
+    @Inject
+    ValidatedService validatedService;
+
+    @Test
+    void validateEvent() {
+        assertDoesNotThrow(() -> validatedService.send(new IntrospectedEvent()));
+
+        var ex = assertThrows(ConstraintViolationException.class, () -> validatedService.send(new NonIntrospectedEvent()));
+
+        assertTrue(ex.getMessage().contains("NonIntrospectedEvent"));
+    }
+
+    @Requires(property = "spec.name", value = "WrongValidationTest")
+    @Singleton
+    @Validated
+    static class ValidatedService {
+
+        <E> void send(@Valid E event) {
+
+        }
+    }
+
+    @Introspected
+    static class IntrospectedEvent {}
+
+    static class NonIntrospectedEvent {}
+}

validation/src/main/java/io/micronaut/validation/validator/DefaultValidator.java

@@ -1360,7 +1360,7 @@ private <R, E> void propagateValidation(DefaultConstraintValidatorContext<R> con
         final BeanIntrospection<E> beanIntrospection = getBeanIntrospection(elementValue, elementType.getType());
         if (beanIntrospection == null) {
             // Error if not introspected
-            ConstraintDescriptor<Annotation> constraintDescriptor = notIntrospectedConstraint(elementType);
+            ConstraintDescriptor<Annotation> constraintDescriptor = notIntrospectedConstraint(elementType, elementValue);
             DefaultConstraintViolation<R> violation = createConstraintViolation(context, leftBean, elementValue, constraintDescriptor);
             context.addViolation(violation);
             return;
@@ -1572,7 +1572,7 @@ public static String requireNonEmpty(String name, String value) {
         return value;
     }
 
-    private static ConstraintDescriptor<Annotation> notIntrospectedConstraint(Argument<?> notIntrospectedArgument) {
+    private static <E> ConstraintDescriptor<Annotation> notIntrospectedConstraint(Argument<E> notIntrospectedArgument, E elementValue) {
         return new ConstraintDescriptor<>() {
 
             @Override
@@ -1607,7 +1607,11 @@ public ConstraintTarget getValidationAppliesTo() {
 
             @Override
             public Map<String, Object> getAttributes() {
-                return Collections.singletonMap("type", notIntrospectedArgument.getType().getName());
+                var argType = notIntrospectedArgument.getType().getName();
+                if (notIntrospectedArgument.isTypeVariable()) {
+                    argType = elementValue.getClass().getName();
+                }
+                return Collections.singletonMap("type", argType);
             }
 
             @Override