Add parent info to each ChangeScreen PatchSetBlock

Parent commit id and short message is placed in a Grid that expands
vertically when a patch set has more than one parent. The text
"Initial Commit" is used when a patch set has no parents.

Change-Id: I5775e8e09b506d9a97d0303e0ba150a926a091e8

gerrit-gwtui/src/main/java/com/google/gerrit/client/GerritCss.java

@@ -131,10 +131,12 @@ public interface GerritCss extends CssResource {
   String menuScreenMenuBar();
   String missingApproval();
   String missingApprovalList();
+  String monospace();
   String needsReview();
   String negscore();
   String noLineLineNumber();
   String noborder();
+  String parentsTable();
   String patchBrowserPopup();
   String patchBrowserPopupBody();
   String patchComments();

gerrit-gwtui/src/main/java/com/google/gerrit/client/changes/ChangeConstants.java

@@ -99,6 +99,8 @@ public interface ChangeConstants extends Constants {
   String patchSetInfoAuthor();
   String patchSetInfoCommitter();
   String patchSetInfoDownload();
+  String patchSetInfoParents();
+  String initialCommit();
 
   String buttonAbandonChangeBegin();
   String buttonAbandonChangeSend();

gerrit-gwtui/src/main/java/com/google/gerrit/client/changes/ChangeConstants.properties

@@ -76,6 +76,8 @@ messageCollapseAll = Collapse All
 patchSetInfoAuthor = Author
 patchSetInfoCommitter = Committer
 patchSetInfoDownload = Download
+patchSetInfoParents = Parent(s)
+initialCommit = Initial Commit
 
 buttonAbandonChangeBegin = Abandon Change
 buttonAbandonChangeSend = Abandon Change

gerrit-gwtui/src/main/java/com/google/gerrit/client/changes/PatchSetComplexDisclosurePanel.java

@@ -54,13 +54,15 @@ import com.google.gwtexpui.clippy.client.CopyableLabel;
 
 import java.util.Collections;
 import java.util.HashSet;
+import java.util.List;
 import java.util.Set;
 
 class PatchSetComplexDisclosurePanel extends ComplexDisclosurePanel implements OpenHandler<DisclosurePanel> {
   private static final int R_AUTHOR = 0;
   private static final int R_COMMITTER = 1;
-  private static final int R_DOWNLOAD = 2;
-  private static final int R_CNT = 3;
+  private static final int R_PARENTS = 2;
+  private static final int R_DOWNLOAD = 3;
+  private static final int R_CNT = 4;
 
   private final ChangeScreen changeScreen;
   private final ChangeDetail changeDetail;
@@ -125,6 +127,7 @@ class PatchSetComplexDisclosurePanel extends ComplexDisclosurePanel implements O
 
     initRow(R_AUTHOR, Util.C.patchSetInfoAuthor());
     initRow(R_COMMITTER, Util.C.patchSetInfoCommitter());
+    initRow(R_PARENTS, Util.C.patchSetInfoParents());
     initRow(R_DOWNLOAD, Util.C.patchSetInfoDownload());
 
     final CellFormatter itfmt = infoTable.getCellFormatter();
@@ -139,6 +142,7 @@ class PatchSetComplexDisclosurePanel extends ComplexDisclosurePanel implements O
     final PatchSetInfo info = detail.getInfo();
     displayUserIdentity(R_AUTHOR, info.getAuthor());
     displayUserIdentity(R_COMMITTER, info.getCommitter());
+    displayParents(info.getParents());
     displayDownload();
 
 
@@ -363,6 +367,28 @@ class PatchSetComplexDisclosurePanel extends ComplexDisclosurePanel implements O
     infoTable.setWidget(row, 1, fp);
   }
 
+  private void displayParents(final List<PatchSetInfo.ParentInfo> parents) {
+    if (parents.size() == 0) {
+      infoTable.setWidget(R_PARENTS, 1, new InlineLabel(Util.C.initialCommit()));
+      return;
+    }
+    final Grid parentsTable = new Grid(parents.size(), 2);
+
+    parentsTable.setStyleName(Gerrit.RESOURCES.css().parentsTable());
+    parentsTable.addStyleName(Gerrit.RESOURCES.css().noborder());
+    final CellFormatter ptfmt = parentsTable.getCellFormatter();
+    int row = 0;
+    for (PatchSetInfo.ParentInfo parent : parents) {
+      parentsTable.setWidget(row, 0, new InlineLabel(parent.id.get()));
+      ptfmt.addStyleName(row, 0, Gerrit.RESOURCES.css().noborder());
+      ptfmt.addStyleName(row, 0, Gerrit.RESOURCES.css().monospace());
+      parentsTable.setWidget(row, 1, new InlineLabel(parent.shortMessage));
+      ptfmt.addStyleName(row, 1, Gerrit.RESOURCES.css().noborder());
+      row++;
+    }
+    infoTable.setWidget(R_PARENTS, 1, parentsTable);
+  }
+
   private void populateActions(final PatchSetDetail detail) {
     final boolean isOpen = changeDetail.getChange().getStatus().isOpen();
     Set<ApprovalCategory.Id> allowed = changeDetail.getCurrentActions();

gerrit-gwtui/src/main/java/com/google/gerrit/client/gerrit.css

@@ -972,6 +972,28 @@ a:hover.downloadLink {
   width: 30em;
 }
 
+.parentsTable {
+  border-style: none;
+  border: 1px 1px 1px 0px;
+  outline: 0px;
+  padding: 0px;
+  border-spacing: 0px;
+  text-align: left;
+  font-family: mono-font;
+  font-size: 10px;
+}
+
+.parentsTable td.noborder {
+  border: none;
+}
+
+.parentsTable td.monospace {
+  font-family: mono-font;
+  font-size: 10px;
+  margin: 0px;
+  padding-left: 0px;
+}
+
 /** SideBySideScreen **/
 .sideBySideScreenSideBySideTable {
   width: 100%;

gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/PatchSetInfo.java

@@ -14,11 +14,26 @@
 
 package com.google.gerrit.reviewdb;
 
+import java.util.List;
+
 
 /**
  * Additional data about a {@link PatchSet} not normally loaded.
  */
 public final class PatchSetInfo {
+  public static class ParentInfo {
+    public RevId id;
+    public String shortMessage;
+
+    public ParentInfo(final RevId id, final String shortMessage) {
+      this.id = id;
+      this.shortMessage = shortMessage;
+    }
+
+    protected ParentInfo() {
+    }
+  }
+
   protected PatchSet.Id key;
 
   /** First line of {@link #message}. */
@@ -33,6 +48,9 @@ public final class PatchSetInfo {
   /** Identity of who committed the patch set to the VCS. */
   protected UserIdentity committer;
 
+  /** List of parents of the patch set. */
+  protected List<ParentInfo> parents;
+
   protected PatchSetInfo() {
   }
 
@@ -79,4 +97,12 @@ public final class PatchSetInfo {
   public void setCommitter(final UserIdentity u) {
     committer = u;
   }
+
+  public void setParents(final List<ParentInfo> p) {
+    parents = p;
+  }
+
+  public List<ParentInfo> getParents() {
+    return parents;
+  }
 }

gerrit-server/src/main/java/com/google/gerrit/server/patch/PatchSetInfoFactory.java

@@ -19,6 +19,7 @@ import com.google.gerrit.reviewdb.Change;
 import com.google.gerrit.reviewdb.PatchSet;
 import com.google.gerrit.reviewdb.PatchSetInfo;
 import com.google.gerrit.reviewdb.Project;
+import com.google.gerrit.reviewdb.RevId;
 import com.google.gerrit.reviewdb.ReviewDb;
 import com.google.gerrit.reviewdb.UserIdentity;
 import com.google.gerrit.server.account.AccountByEmailCache;
@@ -28,6 +29,7 @@ import com.google.gwtorm.client.SchemaFactory;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
+import org.eclipse.jgit.errors.MissingObjectException;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.lib.Repository;
@@ -36,6 +38,8 @@ import org.eclipse.jgit.revwalk.RevWalk;
 
 import java.io.IOException;
 import java.sql.Timestamp;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Set;
 
 
@@ -81,7 +85,9 @@ public class PatchSetInfoFactory {
       try {
         final RevCommit src =
             rw.parseCommit(ObjectId.fromString(patchSet.getRevision().get()));
-        return get(src, patchSetId);
+        PatchSetInfo info = get(src, patchSetId);
+        info.setParents(toParentInfos(src.getParents(), rw));
+        return info;
       } finally {
         rw.release();
       }
@@ -117,4 +123,17 @@ public class PatchSetInfoFactory {
     return u;
   }
 
+  private List<PatchSetInfo.ParentInfo> toParentInfos(final RevCommit[] parents,
+      final RevWalk walk) throws IOException, MissingObjectException {
+    List<PatchSetInfo.ParentInfo> pInfos =
+      new ArrayList<PatchSetInfo.ParentInfo>(parents.length);
+    for (RevCommit parent : parents) {
+      walk.parseBody(parent);
+      RevId rev = new RevId(parent.getId().name());
+      String msg = parent.getShortMessage();
+      pInfos.add(new PatchSetInfo.ParentInfo(rev, msg));
+    }
+    return pInfos;
+  }
+
 }