test: add column mapping test for WebAuthnCredential byte[] length (#286)

Author: devondragon

src/test/java/com/digitalsanctuary/spring/user/persistence/model/WebAuthnCredentialColumnMappingTest.java

@@ -0,0 +1,29 @@
+package com.digitalsanctuary.spring.user.persistence.model;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import java.lang.reflect.Field;
+import jakarta.persistence.Column;
+import org.hibernate.Length;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+@DisplayName("WebAuthnCredential Column Mapping Tests")
+class WebAuthnCredentialColumnMappingTest {
+
+	@ParameterizedTest
+	@ValueSource(strings = {"attestationObject", "attestationClientDataJson", "publicKey"})
+	@DisplayName("should use Length.LONG32 on byte[] fields for cross-database BLOB compatibility")
+	void shouldUseLengthLong32OnBlobFields(String fieldName) throws NoSuchFieldException {
+		Field field = WebAuthnCredential.class.getDeclaredField(fieldName);
+		Column column = field.getAnnotation(Column.class);
+		assertThat(column)
+				.as("Field '%s' must have @Column annotation", fieldName)
+				.isNotNull();
+		assertThat(column.length())
+				.as("Field '%s' @Column length must be Length.LONG32 (%d) to auto-upgrade "
+						+ "to LONGBLOB on MariaDB/MySQL and remain bytea on PostgreSQL",
+						fieldName, Length.LONG32)
+				.isEqualTo(Length.LONG32);
+	}
+}