HHH-13343 : test case

(cherry picked from commit 6f110275ad)

hibernate-core/src/test/java/org/hibernate/bytecode/internal/bytebuddy/EnhanceByteCodeNotInProvidedClassLoaderTest.java

@@ -0,0 +1,68 @@
+/*
+ * Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
+ * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
+ */
+package org.hibernate.bytecode.internal.bytebuddy;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.Arrays;
+
+import org.hibernate.bytecode.enhance.internal.bytebuddy.EnhancerImpl;
+import org.hibernate.bytecode.enhance.spi.DefaultEnhancementContext;
+import org.hibernate.bytecode.enhance.spi.Enhancer;
+
+import org.hibernate.testing.TestForIssue;
+import org.junit.Assert;
+import org.junit.Test;
+
+/**
+ * Tests that bytecode can be enhanced when the original class cannot be loaded from
+ * the ClassLoader provided to ByteBuddy.
+ */
+public class EnhanceByteCodeNotInProvidedClassLoaderTest {
+
+	@Test
+	@TestForIssue( jiraKey = "HHH-13343" )
+	public void test() {
+		Enhancer enhancer = createByteBuddyEnhancer();
+		byte[] buffer = readResource( SimpleEntity.class );
+		// Now use a fake class name so it won't be found in the ClassLoader
+		// provided by DefaultEnhancementContext
+		byte[] enhanced = enhancer.enhance( SimpleEntity.class.getName() + "Fake", buffer );
+		Assert.assertNotNull( "This is null when there have been swallowed exceptions during enhancement. Check Logs!", enhanced );
+		// Make sure enhanced bytecode is different from original bytecode.
+		Assert.assertFalse( Arrays.equals( buffer, enhanced ) );
+	}
+
+	private byte[] readResource(Class<?> clazz) {
+		String internalName = clazz.getName().replace( '.', '/' );
+		String resourceName = internalName + ".class";
+
+		final int BUF_SIZE = 256;
+		byte[] buffer = new byte[BUF_SIZE];
+		ByteArrayOutputStream os = new ByteArrayOutputStream();
+		int readSize = 0;
+		try ( InputStream inputStream = this.getClass().getClassLoader().getResourceAsStream( resourceName ) ) {
+			while ( ( readSize = inputStream.read( buffer ) ) != -1 ) {
+				os.write( buffer, 0, readSize );
+			}
+			os.flush();
+			os.close();
+		}
+		catch (IOException ex) {
+			Assert.fail( "Should not have an IOException here" );
+		}
+		return os.toByteArray();
+	}
+
+	private Enhancer createByteBuddyEnhancer() {
+		ByteBuddyState bytebuddy = new ByteBuddyState();
+		DefaultEnhancementContext enhancementContext = new DefaultEnhancementContext();
+		EnhancerImpl impl = new EnhancerImpl( enhancementContext, bytebuddy );
+		return impl;
+	}
+}