improve exception handling

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/repository/spi/HgIncomingCommand.java

@@ -33,16 +33,20 @@ package sonia.scm.repository.spi;
 
 //~--- non-JDK imports --------------------------------------------------------
 
+import com.aragost.javahg.commands.ExecutionException;
+
 import sonia.scm.repository.Changeset;
 import sonia.scm.repository.ChangesetPagingResult;
 import sonia.scm.repository.HgRepositoryHandler;
 import sonia.scm.repository.Repository;
+import sonia.scm.repository.RepositoryException;
 import sonia.scm.repository.spi.javahg.HgIncomingChangesetCommand;
 
 //~--- JDK imports ------------------------------------------------------------
 
 import java.io.File;
 
+import java.util.Collections;
 import java.util.List;
 
 /**
@@ -53,6 +57,11 @@ public class HgIncomingCommand extends AbstractCommand
   implements IncomingCommand
 {
 
+  /** Field description */
+  private static final int NO_INCOMING_CHANGESETS = 1;
+
+  //~--- constructors ---------------------------------------------------------
+
   /**
    * Constructs ...
    *
@@ -77,10 +86,13 @@ public class HgIncomingCommand extends AbstractCommand
    * @param request
    *
    * @return
+   *
+   * @throws RepositoryException
    */
   @Override
   public ChangesetPagingResult getIncomingChangesets(
     IncomingCommandRequest request)
+    throws RepositoryException
   {
     File remoteRepository = handler.getDirectory(request.getRemoteRepository());
 
@@ -88,8 +100,25 @@ public class HgIncomingCommand extends AbstractCommand
 
     // TODO implement paging
 
-    List<Changeset> changesets =
-      on(repository).execute(remoteRepository.getAbsolutePath());
+    List<Changeset> changesets;
+
+    try
+    {
+
+      changesets = on(repository).execute(remoteRepository.getAbsolutePath());
+
+    }
+    catch (ExecutionException ex)
+    {
+      if (ex.getCommand().getReturnCode() == NO_INCOMING_CHANGESETS)
+      {
+        changesets = Collections.EMPTY_LIST;
+      }
+      else
+      {
+        throw new RepositoryException("could not execute incoming command", ex);
+      }
+    }
 
     return new ChangesetPagingResult(changesets.size(), changesets);
   }

scm-plugins/scm-hg-plugin/src/test/java/sonia/scm/repository/spi/HgIncomingCommandTest.java

@@ -38,6 +38,7 @@ import com.aragost.javahg.Changeset;
 import org.junit.Test;
 
 import sonia.scm.repository.ChangesetPagingResult;
+import sonia.scm.repository.RepositoryException;
 
 import static org.junit.Assert.*;
 
@@ -57,9 +58,11 @@ public class HgIncomingCommandTest extends IncomingOutgoingTestBase
    *
    *
    * @throws IOException
+   * @throws RepositoryException
    */
   @Test
-  public void testGetIncomingChangesets() throws IOException
+  public void testGetIncomingChangesets()
+    throws IOException, RepositoryException
   {
     writeNewFile(outgoing, outgoingDirectory, "a.txt", "Content of file a.txt");
     writeNewFile(outgoing, outgoingDirectory, "b.txt", "Content of file b.txt");
@@ -84,6 +87,56 @@ public class HgIncomingCommandTest extends IncomingOutgoingTestBase
     assertChangesetsEqual(c2, cpr.getChangesets().get(1));
   }
 
+  /**
+   * Method description
+   *
+   *
+   * @throws RepositoryException
+   */
+  @Test
+  public void testGetIncomingChangesetsWithEmptyRepository()
+    throws RepositoryException
+  {
+    HgIncomingCommand cmd = createIncomingCommand();
+    IncomingCommandRequest request = new IncomingCommandRequest();
+
+    request.setRemoteRepository(outgoingRepository);
+
+    ChangesetPagingResult cpr = cmd.getIncomingChangesets(request);
+
+    assertNotNull(cpr);
+    assertEquals(0, cpr.getTotal());
+  }
+
+  /**
+   * Method description
+   *
+   *
+   * @throws IOException
+   * @throws RepositoryException
+   */
+  @Test(expected = RepositoryException.class)
+  public void testGetIncomingChangesetsWithUnrelatedRepository()
+    throws IOException, RepositoryException
+  {
+    writeNewFile(outgoing, outgoingDirectory, "a.txt", "Content of file a.txt");
+    writeNewFile(outgoing, outgoingDirectory, "b.txt", "Content of file b.txt");
+
+    commit(outgoing, "added a and b");
+
+    writeNewFile(incoming, incomingDirectory, "c.txt", "Content of file c.txt");
+    writeNewFile(incoming, incomingDirectory, "d.txt", "Content of file d.txt");
+
+    commit(incoming, "added c and d");
+
+    HgIncomingCommand cmd = createIncomingCommand();
+    IncomingCommandRequest request = new IncomingCommandRequest();
+
+    request.setRemoteRepository(outgoingRepository);
+
+    cmd.getIncomingChangesets(request);
+  }
+
   /**
    * Method description
    *