Stop initCause throwing in readAdvertisedRefs

BasePackConnection::readAdvertisedRefsImpl was creating an exception by
calling `noRepository`, and then blindly calling `initCause` on it. As
`noRepository` can be overridden, it's not guaranteed to be missing a
cause.

BasePackPushConnection overrides `noRepository` and initiates a fetch,
which may throw a `NoRemoteRepositoryException` with a cause.

In this case calling `initCause` threw an `IllegalStateException`.

In order to throw the correct exception, we now return the
BasePackPushConnection exception and suppress the one thrown by
BasePackConnection

Bug: 578511
Change-Id: Ic1018b214be1e83d895979ee6c7cbce3f6765f6f

2 files changed, 119 insertions, 1 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/BasePackConnectionTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/BasePackConnectionTest.java
index 7d438c1dd8..505f334905 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/BasePackConnectionTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/BasePackConnectionTest.java
@@ -15,11 +15,15 @@ import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.not;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertSame;
+import static org.junit.Assert.assertThrows;
 
+import java.io.ByteArrayInputStream;
+import java.io.EOFException;
 import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.Map;
 
+import org.eclipse.jgit.errors.NoRemoteRepositoryException;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectIdRef;
@@ -30,6 +34,16 @@ import org.junit.Test;
 public class BasePackConnectionTest {
 
 	@Test
+	public void testReadAdvertisedRefsShouldThrowExceptionWithOriginalCause() {
+		try (FailingBasePackConnection basePackConnection =
+				new FailingBasePackConnection()) {
+			Exception result = assertThrows(NoRemoteRepositoryException.class,
+					basePackConnection::readAdvertisedRefs);
+			assertEquals(EOFException.class, result.getCause().getClass());
+		}
+	}
+
+	@Test
 	public void testUpdateWithSymRefsAdds() {
 		final Ref mainRef = new ObjectIdRef.Unpeeled(Ref.Storage.LOOSE,
 				"refs/heads/main", ObjectId.fromString(
@@ -244,4 +258,12 @@ public class BasePackConnectionTest {
 		assertEquals(oidName, headRef.getObjectId().name());
 		assertEquals(oidName, mainRef.getObjectId().name());
 	}
-}
\ No newline at end of file
+
+	private static class FailingBasePackConnection extends BasePackConnection {
+		FailingBasePackConnection() {
+			super(new TransportLocal(new URIish(),
+					new java.io.File("")));
+			pckIn = new PacketLineIn(new ByteArrayInputStream(new byte[0]));
+		}
+	}
+}
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/BasePackPushConnectionTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/BasePackPushConnectionTest.java
new file mode 100644
index 0000000000..cf8c5ffe79
--- /dev/null
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/BasePackPushConnectionTest.java
@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2022 Darius Jokilehto <darius.jokilehto+os@gmail.com>
+ * Copyright (c) 2022 Antonio Barone <syntonyze@gmail.com>
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Distribution License v. 1.0 which is available at
+ * https://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+package org.eclipse.jgit.transport;
+
+import org.eclipse.jgit.errors.NoRemoteRepositoryException;
+import org.eclipse.jgit.errors.TransportException;
+import org.eclipse.jgit.internal.JGitText;
+import org.junit.Test;
+
+import java.io.ByteArrayInputStream;
+import java.io.EOFException;
+import java.io.IOException;
+import java.util.Arrays;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.endsWith;
+import static org.hamcrest.Matchers.hasItem;
+import static org.hamcrest.Matchers.instanceOf;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThrows;
+
+public class BasePackPushConnectionTest {
+	@Test
+	public void testNoRemoteRepository() {
+		NoRemoteRepositoryException openFetchException =
+                new NoRemoteRepositoryException( new URIish(), "not found");
+		IOException ioException = new IOException("not read");
+
+		try (FailingBasePackPushConnection fbppc =
+				new FailingBasePackPushConnection(openFetchException)) {
+			TransportException result = fbppc.noRepository(ioException);
+
+			assertEquals(openFetchException, result);
+			assertThat(Arrays.asList(result.getSuppressed()),
+					hasItem(ioException));
+		}
+	}
+
+	@Test
+	public void testPushNotPermitted() {
+		URIish uri = new URIish();
+		TransportException openFetchException = new TransportException(uri,
+				"a transport exception");
+		IOException ioException = new IOException("not read");
+
+		try (FailingBasePackPushConnection fbppc =
+				new FailingBasePackPushConnection(openFetchException)) {
+			TransportException result = fbppc.noRepository(ioException);
+
+			assertEquals(TransportException.class, result.getClass());
+			assertThat(result.getMessage(),
+					endsWith(JGitText.get().pushNotPermitted));
+			assertEquals(openFetchException, result.getCause());
+			assertThat(Arrays.asList(result.getSuppressed()),
+					hasItem(ioException));
+		}
+	}
+
+	@Test
+	public void testReadAdvertisedRefPropagatesCauseAndSuppressedExceptions() {
+		IOException ioException = new IOException("not read");
+		try (FailingBasePackPushConnection basePackConnection =
+				new FailingBasePackPushConnection(
+						new NoRemoteRepositoryException(
+								new URIish(), "not found", ioException))) {
+			Exception result = assertThrows(NoRemoteRepositoryException.class,
+					basePackConnection::readAdvertisedRefs);
+			assertEquals(ioException, result.getCause());
+			assertThat(Arrays.asList(result.getSuppressed()),
+					hasItem(instanceOf(EOFException.class)));
+		}
+	}
+
+	private static class FailingBasePackPushConnection
+			extends BasePackPushConnection {
+		FailingBasePackPushConnection(TransportException openFetchException) {
+			super(new TransportLocal(new URIish(),
+					new java.io.File("")) {
+				@Override public FetchConnection openFetch()
+						throws TransportException {
+					throw openFetchException;
+				}
+			});
+			pckIn = new PacketLineIn(new ByteArrayInputStream(new byte[0]));
+		}
+	}
+}