CreateTag: Allow revision in input to be empty

If a revision in the input is not specified we default to the HEAD
revision, but when the revision in the input was empty we failed with
400 Bad Request. Be more tolerant and consistent and default to the HEAD
revision too if the specified revision is empty.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I78afe991d274d0feba134612382a65c76916cfd5

2 files changed, 34 insertions, 1 deletions

diff --git a/java/com/google/gerrit/server/restapi/project/CreateTag.java b/java/com/google/gerrit/server/restapi/project/CreateTag.java
index e72deaf255..cdeba62800 100644
--- a/java/com/google/gerrit/server/restapi/project/CreateTag.java
+++ b/java/com/google/gerrit/server/restapi/project/CreateTag.java
@@ -87,7 +87,7 @@ public class CreateTag implements RestCollectionCreateView<ProjectResource, TagR
     if (input.ref != null && !ref.equals(input.ref)) {
       throw new BadRequestException("ref must match URL");
     }
-    if (input.revision == null) {
+    if (Strings.isNullOrEmpty(input.revision)) {
       input.revision = Constants.HEAD;
     }
 
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/TagsIT.java b/javatests/com/google/gerrit/acceptance/rest/project/TagsIT.java
index d4edc0de95..8e5f361cbc 100644
--- a/javatests/com/google/gerrit/acceptance/rest/project/TagsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/project/TagsIT.java
@@ -35,6 +35,7 @@ import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import java.sql.Timestamp;
 import java.util.List;
+import org.eclipse.jgit.revwalk.RevCommit;
 import org.junit.Test;
 
 @NoHttpd
@@ -326,6 +327,38 @@ public class TagsIT extends AbstractDaemonTest {
     tag(input.ref).create(input);
   }
 
+  @Test
+  public void noBaseRevision() throws Exception {
+    grantTagPermissions();
+
+    // If revision is not specified, the tag is created based on HEAD, which points to master.
+    RevCommit expectedRevision = getRemoteHead(project, "master");
+
+    TagInput input = new TagInput();
+    input.ref = "test";
+    input.revision = null;
+
+    TagInfo result = tag(input.ref).create(input).get();
+    assertThat(result.ref).isEqualTo(R_TAGS + input.ref);
+    assertThat(result.revision).isEqualTo(expectedRevision.name());
+  }
+
+  @Test
+  public void emptyBaseRevision() throws Exception {
+    grantTagPermissions();
+
+    // If revision is not specified, the tag is created based on HEAD, which points to master.
+    RevCommit expectedRevision = getRemoteHead(project, "master");
+
+    TagInput input = new TagInput();
+    input.ref = "test";
+    input.revision = "";
+
+    TagInfo result = tag(input.ref).create(input).get();
+    assertThat(result.ref).isEqualTo(R_TAGS + input.ref);
+    assertThat(result.revision).isEqualTo(expectedRevision.name());
+  }
+
   private void assertTagList(FluentIterable<String> expected, List<TagInfo> actual)
       throws Exception {
     assertThat(actual).hasSize(expected.size());