Store subject and original subject in notedb

This adds a 'Subject' footer to the commit message of the
refs/changes/XX/YYYY/meta notes branch when the change is created and
whenever a new patch set with a different subject is added.

The current subject is taken from most recent commit on the notes
branch that contains a 'Subject' footer. The original subject is taken
from the first commit on the notes branch.

Tests which manually insert new changes must be adapted so that the
initial commit to the notes branch contains the subject.

In order to set the 'Subject' footer only when the subject was
changed, we must compare the new subject to the old subject when a new
patch set is inserted. To be able to access the old subject when a
a new patch set is created, PatchSetInserter must ensure that the body
of the commit was parsed. Otherwise the subject would not be available
and trying to get it would fail with a NullPointerException.

Change-Id: I71bfe88e16c3e0b41530f399441b16e2cd44f59e
Signed-off-by: Edwin Kempin <ekempin@google.com>

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/server/change/ConsistencyCheckerIT.java

@@ -585,6 +585,7 @@ public class ConsistencyCheckerIT extends AbstractDaemonTest {
 
     ChangeUpdate u = changeUpdateFactory.create(
         changeControlFactory.controlFor(c, userFactory.create(adminId)));
+    u.setSubject(c.getSubject());
     u.setBranch(c.getDest().get());
     u.commit();
 

gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/Change.java

@@ -563,10 +563,18 @@ public final class Change {
     return subject;
   }
 
+  public void setSubject(String subject) {
+    this.subject = subject;
+  }
+
   public String getOriginalSubject() {
     return originalSubject != null ? originalSubject : subject;
   }
 
+  public void setOriginalSubject(String originalSubject) {
+    this.originalSubject = originalSubject;
+  }
+
   /** Get the id of the most current {@link PatchSet} in this change. */
   public PatchSet.Id currentPatchSetId() {
     if (currentPatchSetId > 0) {

gerrit-server/src/main/java/com/google/gerrit/server/PatchSetUtil.java

@@ -28,7 +28,7 @@ import com.google.gwtorm.server.OrmException;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
-import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.revwalk.RevCommit;
 
 import java.sql.Timestamp;
 import java.util.Collections;
@@ -61,7 +61,7 @@ public class PatchSetUtil {
   }
 
   public PatchSet insert(ReviewDb db, ChangeUpdate update, PatchSet.Id psId,
-      ObjectId id, boolean draft, Iterable<String> groups,
+      RevCommit commit, boolean draft, Iterable<String> groups,
       String pushCertificate) throws OrmException {
     Change.Id changeId = update.getChange().getId();
     checkArgument(psId.getParentKey().equals(changeId),
@@ -75,7 +75,7 @@ public class PatchSetUtil {
     }
 
     PatchSet ps = new PatchSet(psId);
-    ps.setRevision(new RevId(id.name()));
+    ps.setRevision(new RevId(commit.name()));
     ps.setUploader(update.getUser().getAccountId());
     ps.setCreatedOn(new Timestamp(update.getWhen().getTime()));
     ps.setDraft(draft);
@@ -83,6 +83,10 @@ public class PatchSetUtil {
     ps.setPushCertificate(pushCertificate);
     db.patchSets().insert(Collections.singleton(ps));
 
+    if (!update.getChange().getSubject().equals(commit.getShortMessage())) {
+      update.setSubject(commit.getShortMessage());
+    }
+
     if (migration.writeChanges()) {
       // TODO(dborowitz): Write to notedb.
     }

gerrit-server/src/main/java/com/google/gerrit/server/change/ChangeInserter.java

@@ -296,7 +296,8 @@ public class ChangeInserter extends BatchUpdate.InsertChangeOp {
     ctx.getChange().setCurrentPatchSet(patchSetInfo);
 
     ChangeUpdate update = ctx.getUpdate(psId);
-    update.setSubject("Create change");
+    update.setSubjectForCommit("Create change");
+    update.setSubject(change.getSubject());
     update.setBranch(change.getDest().get());
     update.setTopic(change.getTopic());
 

gerrit-server/src/main/java/com/google/gerrit/server/change/PatchSetInserter.java

@@ -210,7 +210,7 @@ public class PatchSetInserter extends BatchUpdate.Op {
 
     change = ctx.getChange();
     ChangeUpdate update = ctx.getUpdate(psId);
-    update.setSubject("Create patch set " + psId.get());
+    update.setSubjectForCommit("Create patch set " + psId.get());
 
     if (!change.getStatus().isOpen() && !allowClosed) {
       throw new InvalidChangeOperationException(String.format(
@@ -222,6 +222,7 @@ public class PatchSetInserter extends BatchUpdate.Op {
       PatchSet prevPs = psUtil.current(ctx.getDb(), ctx.getNotes());
       newGroups = prevPs != null ? prevPs.getGroups() : null;
     }
+    ctx.getRevWalk().parseBody(commit);
     patchSet = psUtil.insert(ctx.getDb(), ctx.getUpdate(psId), psId, commit,
         draft, newGroups, null);
 

gerrit-server/src/main/java/com/google/gerrit/server/git/ReceiveCommits.java

@@ -2241,7 +2241,7 @@ public class ReceiveCommits {
 
       Map<String, Short> approvals = new HashMap<>();
       ChangeUpdate update = updateFactory.create(changeCtl, createdOn);
-      update.setSubject("Create patch set " + psId.get());
+      update.setSubjectForCommit("Create patch set " + psId.get());
       update.setPatchSetId(psId);
 
       if (magicBranch != null) {

gerrit-server/src/main/java/com/google/gerrit/server/notedb/ChangeNoteUtil.java

@@ -33,6 +33,7 @@ public class ChangeNoteUtil {
   static final FooterKey FOOTER_LABEL = new FooterKey("Label");
   static final FooterKey FOOTER_PATCH_SET = new FooterKey("Patch-set");
   static final FooterKey FOOTER_STATUS = new FooterKey("Status");
+  static final FooterKey FOOTER_SUBJECT = new FooterKey("Subject");
   static final FooterKey FOOTER_SUBMISSION_ID = new FooterKey("Submission-id");
   static final FooterKey FOOTER_SUBMITTED_WITH =
       new FooterKey("Submitted-with");

gerrit-server/src/main/java/com/google/gerrit/server/notedb/ChangeNotes.java

@@ -266,6 +266,8 @@ public class ChangeNotes extends AbstractChangeNotes<ChangeNotes> {
       allChangeMessages = parser.buildAllMessages();
       comments = ImmutableListMultimap.copyOf(parser.comments);
       noteMap = parser.commentNoteMap;
+      change.setOriginalSubject(parser.originalSubject);
+      change.setSubject(parser.subject);
       change.setDest(new Branch.NameKey(getProjectName(), parser.branch));
       change.setTopic(Strings.emptyToNull(parser.topic));
       change.setCreatedOn(parser.createdOn);

gerrit-server/src/main/java/com/google/gerrit/server/notedb/ChangeNotesParser.java

@@ -19,6 +19,7 @@ import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_HASHTAGS;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_LABEL;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_PATCH_SET;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_STATUS;
+import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_SUBJECT;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_SUBMISSION_ID;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_SUBMITTED_WITH;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_TOPIC;
@@ -91,6 +92,8 @@ class ChangeNotesParser implements AutoCloseable {
   Timestamp createdOn;
   Timestamp lastUpdatedOn;
   Account.Id ownerId;
+  String subject;
+  String originalSubject;
   String submissionId;
 
   private final Change.Id changeId;
@@ -177,6 +180,10 @@ class ChangeNotesParser implements AutoCloseable {
     PatchSet.Id psId = parsePatchSetId(commit);
     Account.Id accountId = parseIdent(commit);
     ownerId = accountId;
+    if (subject == null) {
+      subject = parseSubject(commit);
+    }
+    originalSubject = parseSubject(commit);
     parseChangeMessage(psId, accountId, commit);
     if (topic == null) {
       topic = parseTopic(commit);
@@ -205,35 +212,31 @@ class ChangeNotesParser implements AutoCloseable {
 
   private String parseSubmissionId(RevCommit commit)
       throws ConfigInvalidException {
-    List<String> submissionIdLines = commit.getFooterLines(FOOTER_SUBMISSION_ID);
+    return parseOneFooter(commit, FOOTER_SUBMISSION_ID);
-    if (submissionIdLines.isEmpty()) {
-      return null;
-    } else if (submissionIdLines.size() > 1) {
-      throw expectedOneFooter(FOOTER_SUBMISSION_ID, submissionIdLines);
-    }
-    return submissionIdLines.get(0);
   }
 
-  private String parseBranch(RevCommit commit)
+  private String parseBranch(RevCommit commit) throws ConfigInvalidException {
-      throws ConfigInvalidException {
+    String branch = parseOneFooter(commit, FOOTER_BRANCH);
-    List<String> branchLines = commit.getFooterLines(FOOTER_BRANCH);
+    return branch != null ? RefNames.fullName(branch) : null;
-    if (branchLines.isEmpty()) {
-      return null;
-    } else if (branchLines.size() > 1) {
-      throw expectedOneFooter(FOOTER_BRANCH, branchLines);
-    }
-    return RefNames.fullName(branchLines.get(0));
   }
 
-  private String parseTopic(RevCommit commit)
+  private String parseSubject(RevCommit commit) throws ConfigInvalidException {
-      throws ConfigInvalidException {
+    return parseOneFooter(commit, FOOTER_SUBJECT);
-    List<String> topicLines = commit.getFooterLines(FOOTER_TOPIC);
-    if (topicLines.isEmpty()) {
-      return null;
-    } else if (topicLines.size() > 1) {
-      throw expectedOneFooter(FOOTER_TOPIC, topicLines);
   }
-    return topicLines.get(0);
+
+  private String parseTopic(RevCommit commit) throws ConfigInvalidException {
+    return parseOneFooter(commit, FOOTER_TOPIC);
+  }
+
+  private String parseOneFooter(RevCommit commit, FooterKey footerKey)
+      throws ConfigInvalidException {
+    List<String> footerLines = commit.getFooterLines(footerKey);
+    if (footerLines.isEmpty()) {
+      return null;
+    } else if (footerLines.size() > 1) {
+      throw expectedOneFooter(footerKey, footerLines);
+    }
+    return footerLines.get(0);
   }
 
   private void parseHashtags(RevCommit commit) throws ConfigInvalidException {
@@ -545,6 +548,9 @@ class ChangeNotesParser implements AutoCloseable {
     if (branch == null) {
       missing.add(FOOTER_BRANCH);
     }
+    if (originalSubject == null || subject == null) {
+      missing.add(FOOTER_SUBJECT);
+    }
     if (!missing.isEmpty()) {
       throw parseException("Missing footers: " + Joiner.on(", ")
           .join(Lists.transform(missing, new Function<FooterKey, String>() {

gerrit-server/src/main/java/com/google/gerrit/server/notedb/ChangeRebuilder.java

@@ -318,11 +318,12 @@ public class ChangeRebuilder {
     @Override
     void apply(ChangeUpdate update) {
       checkUpdate(update);
+      update.setSubject(change.getSubject());
       if (ps.getPatchSetId() == 1) {
-        update.setSubject("Create change");
+        update.setSubjectForCommit("Create change");
         update.setBranch(change.getDest().get());
       } else {
-        update.setSubject("Create patch set " + ps.getPatchSetId());
+        update.setSubjectForCommit("Create patch set " + ps.getPatchSetId());
       }
     }
   }

gerrit-server/src/main/java/com/google/gerrit/server/notedb/ChangeUpdate.java

@@ -20,6 +20,7 @@ import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_HASHTAGS;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_LABEL;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_PATCH_SET;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_STATUS;
+import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_SUBJECT;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_SUBMISSION_ID;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_SUBMITTED_WITH;
 import static com.google.gerrit.server.notedb.ChangeNoteUtil.FOOTER_TOPIC;
@@ -93,11 +94,12 @@ public class ChangeUpdate extends AbstractChangeUpdate {
   }
 
   private final AccountCache accountCache;
+  private String commitSubject;
+  private String subject;
   private final Table<String, Account.Id, Optional<Short>> approvals;
   private final Map<Account.Id, ReviewerStateInternal> reviewers;
   private String branch;
   private Change.Status status;
-  private String subject;
   private List<SubmitRecord> submitRecords;
   private String submissionId;
   private final CommentsInNotesUtil commentsUtil;
@@ -219,6 +221,10 @@ public class ChangeUpdate extends AbstractChangeUpdate {
         "no submit records specified at submit time");
   }
 
+  public void setSubjectForCommit(String commitSubject) {
+    this.commitSubject = commitSubject;
+  }
+
   public void setSubject(String subject) {
     this.subject = subject;
   }
@@ -435,8 +441,8 @@ public class ChangeUpdate extends AbstractChangeUpdate {
 
     int ps = psId != null ? psId.get() : getChange().currentPatchSetId().get();
     StringBuilder msg = new StringBuilder();
-    if (subject != null) {
+    if (commitSubject != null) {
-      msg.append(subject);
+      msg.append(commitSubject);
     } else {
       msg.append("Update patch set ").append(ps);
     }
@@ -450,6 +456,10 @@ public class ChangeUpdate extends AbstractChangeUpdate {
 
     addFooter(msg, FOOTER_PATCH_SET, ps);
 
+    if (subject != null) {
+      addFooter(msg, FOOTER_SUBJECT, subject);
+    }
+
     if (branch != null) {
       addFooter(msg, FOOTER_BRANCH, branch);
     }
@@ -526,7 +536,8 @@ public class ChangeUpdate extends AbstractChangeUpdate {
   }
 
   private boolean isEmpty() {
-    return approvals.isEmpty()
+    return commitSubject == null
+        && approvals.isEmpty()
         && changeMessage == null
         && comments.isEmpty()
         && reviewers.isEmpty()

gerrit-server/src/test/java/com/google/gerrit/server/change/CommentsTest.java

@@ -322,6 +322,7 @@ public class CommentsTest extends GerritServerTests {
   private Change newChange() throws Exception {
     Change c = TestChanges.newChange(project, changeOwner.getAccountId());
     ChangeUpdate u = newUpdate(c, changeOwner);
+    u.setSubject(c.getSubject());
     u.setBranch(c.getDest().get());
     u.commit();
     return c;

gerrit-server/src/test/java/com/google/gerrit/server/notedb/AbstractChangeNotesTest.java

@@ -166,6 +166,7 @@ public class AbstractChangeNotesTest extends GerritBaseTests {
       throws IOException, OrmException, ConfigInvalidException {
     Change c = TestChanges.newChange(project, changeOwner.getAccountId());
     ChangeUpdate u = newUpdate(c, changeOwner);
+    u.setSubject(c.getSubject());
     u.setBranch(c.getDest().get());
     u.commit();
     return c;

gerrit-server/src/test/java/com/google/gerrit/server/notedb/ChangeNotesParserTest.java

@@ -51,7 +51,8 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
     assertParseSucceeds("Update change\n"
         + "\n"
         + "Branch: refs/heads/master\n"
-        + "Patch-Set: 1\n");
+        + "Patch-Set: 1\n"
+        + "Subject: This is a test change\n");
     assertParseFails(writeCommit("Update change\n"
         + "\n"
         + "Patch-Set: 1\n",
@@ -70,12 +71,14 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
         + "\n"
         + "Branch: refs/heads/master\n"
         + "Patch-Set: 1\n"
-        + "Status: NEW\n");
+        + "Status: NEW\n"
+        + "Subject: This is a test change\n");
     assertParseSucceeds("Update change\n"
         + "\n"
         + "Branch: refs/heads/master\n"
         + "Patch-Set: 1\n"
-        + "Status: new\n");
+        + "Status: new\n"
+        + "Subject: This is a test change\n");
     assertParseFails("Update change\n"
         + "\n"
         + "Patch-Set: 1\n"
@@ -92,7 +95,8 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
     assertParseSucceeds("Update change\n"
         + "\n"
         + "Branch: refs/heads/master\n"
-        + "Patch-Set: 1\n");
+        + "Patch-Set: 1\n"
+        + "Subject: This is a test change\n");
     assertParseFails("Update change\n"
         + "\n");
     assertParseFails("Update change\n"
@@ -102,7 +106,8 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
     assertParseSucceeds("Update change\n"
         + "\n"
         + "Branch: refs/heads/master\n"
-        + "Patch-Set: 1\n");
+        + "Patch-Set: 1\n"
+        + "Subject: This is a test change\n");
     assertParseFails("Update change\n"
         + "\n"
         + "Patch-Set: x\n");
@@ -117,13 +122,15 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
         + "Label: Label1=+1\n"
         + "Label: Label2=1\n"
         + "Label: Label3=0\n"
-        + "Label: Label4=-1\n");
+        + "Label: Label4=-1\n"
+        + "Subject: This is a test change\n");
     assertParseSucceeds("Update change\n"
         + "\n"
         + "Branch: refs/heads/master\n"
         + "Patch-Set: 1\n"
         + "Label: -Label1\n"
-        + "Label: -Label1 Other Account <2@gerrit>\n");
+        + "Label: -Label1 Other Account <2@gerrit>\n"
+        + "Subject: This is a test change\n");
     assertParseFails("Update change\n"
         + "\n"
         + "Patch-Set: 1\n"
@@ -156,6 +163,7 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
         + "\n"
         + "Branch: refs/heads/master\n"
         + "Patch-Set: 1\n"
+        + "Subject: This is a test change\n"
         + "Submitted-with: NOT_READY\n"
         + "Submitted-with: OK: Verified: Change Owner <1@gerrit>\n"
         + "Submitted-with: NEED: Code-Review\n"
@@ -186,6 +194,7 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
         + "\n"
         + "Branch: refs/heads/master\n"
         + "Patch-Set: 1\n"
+        + "Subject: This is a test change\n"
         + "Submission-id: 1-1453387607626-96fabc25");
     assertParseFails("Update change\n"
         + "\n"
@@ -201,7 +210,8 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
         + "Branch: refs/heads/master\n"
         + "Patch-Set: 1\n"
         + "Reviewer: Change Owner <1@gerrit>\n"
-        + "CC: Other Account <2@gerrit>\n");
+        + "CC: Other Account <2@gerrit>\n"
+        + "Subject: This is a test change\n");
     assertParseFails("Update change\n"
         + "\n"
         + "Patch-Set: 1\n"
@@ -214,12 +224,14 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
         + "\n"
         + "Branch: refs/heads/master\n"
         + "Patch-Set: 1\n"
-        + "Topic: Some Topic");
+        + "Topic: Some Topic\n"
+        + "Subject: This is a test change\n");
     assertParseSucceeds("Update change\n"
         + "\n"
         + "Branch: refs/heads/master\n"
         + "Patch-Set: 1\n"
-        + "Topic:");
+        + "Topic:\n"
+        + "Subject: This is a test change\n");
     assertParseFails("Update change\n"
         + "\n"
         + "Patch-Set: 1\n"
@@ -232,11 +244,13 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
     assertParseSucceeds("Update change\n"
         + "\n"
         + "Branch: refs/heads/master\n"
-        + "Patch-Set: 1");
+        + "Patch-Set: 1\n"
+        + "Subject: This is a test change\n");
     assertParseSucceeds("Update change\n"
         + "\n"
         + "Branch: master\n"
-        + "Patch-Set: 1");
+        + "Patch-Set: 1\n"
+        + "Subject: This is a test change\n");
     assertParseFails("Update change\n"
         + "\n"
         + "Patch-Set: 1\n"
@@ -244,6 +258,20 @@ public class ChangeNotesParserTest extends AbstractChangeNotesTest {
         + "Branch: refs/heads/stable");
   }
 
+  @Test
+  public void parseSubject() throws Exception {
+    assertParseSucceeds("Update change\n"
+        + "\n"
+        + "Patch-Set: 1\n"
+        + "Branch: refs/heads/master\n"
+        + "Subject: Some subject of a change\n");
+    assertParseFails("Update change\n"
+        + "\n"
+        + "Patch-Set: 1\n"
+        + "Subject: Some subject of a change\n"
+        + "Subject: Some other subject\n");
+  }
+
   private RevCommit writeCommit(String body) throws Exception {
     return writeCommit(body, ChangeNoteUtil.newIdent(
         changeOwner.getAccount(), TimeUtil.nowTs(), serverIdent,

gerrit-server/src/test/java/com/google/gerrit/server/notedb/ChangeNotesTest.java

@@ -350,7 +350,7 @@ public class ChangeNotesTest extends AbstractChangeNotesTest {
   public void submitRecords() throws Exception {
     Change c = newChange();
     ChangeUpdate update = newUpdate(c, changeOwner);
-    update.setSubject("Submit patch set 1");
+    update.setSubjectForCommit("Submit patch set 1");
 
     update.merge("1-1453387607626-96fabc25", ImmutableList.of(
         submitRecord("NOT_READY", null,
@@ -380,7 +380,7 @@ public class ChangeNotesTest extends AbstractChangeNotesTest {
   public void latestSubmitRecordsOnly() throws Exception {
     Change c = newChange();
     ChangeUpdate update = newUpdate(c, changeOwner);
-    update.setSubject("Submit patch set 1");
+    update.setSubjectForCommit("Submit patch set 1");
     update.merge("1-1453387607626-96fabc25", ImmutableList.of(
         submitRecord("OK", null,
           submitLabel("Code-Review", "OK", otherUser.getAccountId()))));
@@ -388,7 +388,7 @@ public class ChangeNotesTest extends AbstractChangeNotesTest {
 
     incrementPatchSet(c);
     update = newUpdate(c, changeOwner);
-    update.setSubject("Submit patch set 2");
+    update.setSubjectForCommit("Submit patch set 2");
     update.merge("1-1453387901516-5d1e2450", ImmutableList.of(
         submitRecord("OK", null,
           submitLabel("Code-Review", "OK", changeOwner.getAccountId()))));
@@ -511,6 +511,32 @@ public class ChangeNotesTest extends AbstractChangeNotesTest {
         new Branch.NameKey(project, otherBranch));
   }
 
+  @Test
+  public void subjectChangeNotes() throws Exception {
+    Change c = newChange();
+
+    ChangeNotes notes = newNotes(c);
+    assertThat(notes.getChange().getSubject()).isEqualTo(c.getSubject());
+    assertThat(notes.getChange().getOriginalSubject()).isEqualTo(c.getSubject());
+
+    // An unrelated update doesn't affect the subject
+    ChangeUpdate update = newUpdate(c, changeOwner);
+    update.setTopic("topic"); // Change something to get a new commit.
+    update.commit();
+    notes = newNotes(c);
+    assertThat(notes.getChange().getSubject()).isEqualTo(c.getSubject());
+    assertThat(notes.getChange().getOriginalSubject()).isEqualTo(c.getSubject());
+
+    // An update of the subject doesn't affect the original subject
+    update = newUpdate(c, changeOwner);
+    String newSubject = "other subject";
+    update.setSubject(newSubject);
+    update.commit();
+    notes = newNotes(c);
+    assertThat(notes.getChange().getSubject()).isEqualTo(newSubject);
+    assertThat(notes.getChange().getOriginalSubject()).isEqualTo(c.getSubject());
+  }
+
   @Test
   public void ownerChangeNotes() throws Exception {
     Change c = newChange();
@@ -560,7 +586,7 @@ public class ChangeNotesTest extends AbstractChangeNotesTest {
   @Test
   public void emptyExceptSubject() throws Exception {
     ChangeUpdate update = newUpdate(newChange(), changeOwner);
-    update.setSubject("Create change");
+    update.setSubjectForCommit("Create change");
     update.commit();
     assertThat(update.getRevision()).isNotNull();
   }

gerrit-server/src/test/java/com/google/gerrit/server/notedb/CommitMessageOutputTest.java

@@ -106,7 +106,7 @@ public class CommitMessageOutputTest extends AbstractChangeNotesTest {
   public void submitCommitFormat() throws Exception {
     Change c = newChange();
     ChangeUpdate update = newUpdate(c, changeOwner);
-    update.setSubject("Submit patch set 1");
+    update.setSubjectForCommit("Submit patch set 1");
 
     update.merge("1-1453387607626-96fabc25", ImmutableList.of(
         submitRecord("NOT_READY", null,
@@ -172,7 +172,7 @@ public class CommitMessageOutputTest extends AbstractChangeNotesTest {
   public void submitWithErrorMessage() throws Exception {
     Change c = newChange();
     ChangeUpdate update = newUpdate(c, changeOwner);
-    update.setSubject("Submit patch set 1");
+    update.setSubjectForCommit("Submit patch set 1");
 
     update.merge("1-1453387607626-96fabc25", ImmutableList.of(
         submitRecord("RULE_ERROR", "Problem with patch set:\n1")));