Merge branch 'stable-3.0' into stable-3.1

* stable-3.0:
  Test cherry-pick to a non-existing branch
  CherryPick: Do not fail with ISE if non-existing commit is specified as base

Change-Id: I51e9be4a80f10e3c86c4665e9e12ad71763bd840

java/com/google/gerrit/server/restapi/change/CherryPickChange.java

@@ -70,6 +70,7 @@ import java.util.Set;
 import java.util.TimeZone;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.errors.InvalidObjectIdException;
+import org.eclipse.jgit.errors.MissingObjectException;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.ObjectReader;
@@ -381,7 +382,14 @@ public class CherryPickChange {
       throw new BadRequestException(String.format("Base %s doesn't represent a valid SHA-1", base));
     }
 
-    RevCommit baseCommit = revWalk.parseCommit(baseObjectId);
+    RevCommit baseCommit;
+    try {
+      baseCommit = revWalk.parseCommit(baseObjectId);
+    } catch (MissingObjectException e) {
+      throw new UnprocessableEntityException(
+          String.format("Base %s doesn't exist", baseObjectId.name()), e);
+    }
+
     InternalChangeQuery changeQuery = queryProvider.get();
     changeQuery.enforceVisibility(true);
     List<ChangeData> changeDatas = changeQuery.byBranchCommit(project, destRef.getName(), base);

javatests/com/google/gerrit/acceptance/api/revision/RevisionIT.java

@@ -53,6 +53,7 @@ import com.google.gerrit.entities.Account;
 import com.google.gerrit.entities.BranchNameKey;
 import com.google.gerrit.entities.Change;
 import com.google.gerrit.entities.PatchSetApproval;
+import com.google.gerrit.entities.RefNames;
 import com.google.gerrit.extensions.api.changes.ChangeApi;
 import com.google.gerrit.extensions.api.changes.CherryPickInput;
 import com.google.gerrit.extensions.api.changes.DraftApi;
@@ -973,6 +974,42 @@ public class RevisionIT extends AbstractDaemonTest {
     assertCherryPickResult(changeInfo, input, srcChange.getChangeId());
   }
 
+  @Test
+  public void cherryPickToNonExistingBranch() throws Exception {
+    PushOneCommit.Result result = createChange();
+
+    CherryPickInput input = new CherryPickInput();
+    input.message = "foo bar";
+    input.destination = "non-existing";
+    // TODO(ekempin): This should rather result in an UnprocessableEntityException.
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.changes().id(result.getChangeId()).current().cherryPick(input));
+    assertThat(thrown)
+        .hasMessageThat()
+        .isEqualTo(
+            String.format("Branch %s does not exist.", RefNames.REFS_HEADS + input.destination));
+  }
+
+  @Test
+  public void cherryPickToNonExistingBaseCommit() throws Exception {
+    createBranch(BranchNameKey.create(project, "foo"));
+    PushOneCommit.Result result = createChange();
+
+    CherryPickInput input = new CherryPickInput();
+    input.message = "foo bar";
+    input.destination = "foo";
+    input.base = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef";
+    UnprocessableEntityException thrown =
+        assertThrows(
+            UnprocessableEntityException.class,
+            () -> gApi.changes().id(result.getChangeId()).current().cherryPick(input));
+    assertThat(thrown)
+        .hasMessageThat()
+        .isEqualTo(String.format("Base %s doesn't exist", input.base));
+  }
+
   @Test
   public void canRebase() throws Exception {
     PushOneCommit push = pushFactory.create(admin.newIdent(), testRepo);