Add Follow-Up change UiAction to change screen

Change-Id: If4c9ef331a4646c736720f22fa9f921962f7147f

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/common/ChangeInfo.java

@@ -39,5 +39,6 @@ public class ChangeInfo {
   public Map<String, LabelInfo> labels;
   public Collection<ChangeMessageInfo> messages;
   public Map<String, RevisionInfo> revisions;
+  public String baseChange;
   public int _number;
 }

gerrit-gwtui/src/main/java/com/google/gerrit/client/admin/CreateChangeAction.java

@@ -36,7 +36,7 @@ class CreateChangeAction {
       @Override
       public void onSend() {
         ChangeApi.createChange(project, getDestinationBranch(),
-          message.getText(),
+          message.getText(), null,
           new GerritCallback<ChangeInfo>() {
             @Override
             public void onSuccess(ChangeInfo result) {

gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Actions.java

@@ -39,7 +39,7 @@ class Actions extends Composite {
   private static final String[] CORE = {
     "abandon", "restore", "revert", "topic",
     "cherrypick", "submit", "rebase", "message",
-    "publish", "/"};
+    "publish", "followup", "/"};
 
   interface Binder extends UiBinder<FlowPanel, Actions> {}
   private static final Binder uiBinder = GWT.create(Binder.class);
@@ -61,12 +61,17 @@ class Actions extends Composite {
   @UiField Button restore;
   private RestoreAction restoreAction;
 
+  @UiField Button followUp;
+  private FollowUpAction followUpAction;
+
   private Change.Id changeId;
   private ChangeInfo changeInfo;
   private String revision;
   private String project;
   private String subject;
   private String message;
+  private String branch;
+  private String key;
   private boolean canSubmit;
 
   Actions() {
@@ -84,6 +89,8 @@ class Actions extends Composite {
     project = info.project();
     subject = commit.subject();
     message = commit.message();
+    branch = info.branch();
+    key = info.change_id();
     changeInfo = info;
 
     initChangeActions(info, hasUser);
@@ -102,6 +109,7 @@ class Actions extends Composite {
       a2b(actions, "abandon", abandon);
       a2b(actions, "restore", restore);
       a2b(actions, "revert", revert);
+      a2b(actions, "followup", followUp);
       for (String id : filterNonCore(actions)) {
         add(new ActionButton(info, actions.get(id)));
       }
@@ -176,6 +184,15 @@ class Actions extends Composite {
     return submit.isVisible() && submit.isEnabled();
   }
 
+  @UiHandler("followUp")
+  void onFollowUp(ClickEvent e) {
+    if (followUpAction == null) {
+      followUpAction = new FollowUpAction(followUp, project,
+          branch, key);
+    }
+    followUpAction.show();
+  }
+
   @UiHandler("abandon")
   void onAbandon(ClickEvent e) {
     if (abandonAction == null) {

gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Actions.ui.xml

@@ -108,6 +108,9 @@ limitations under the License.
     <g:Button ui:field='restore' styleName='{style.red}' visible='false'>
       <div><ui:msg>Restore</ui:msg></div>
     </g:Button>
+    <g:Button ui:field='followUp' styleName='' visible='false'>
+      <div><ui:msg>Follow-Up</ui:msg></div>
+    </g:Button>
 
     <g:Button ui:field='submit' styleName='{style.submit}' visible='false'/>
   </g:FlowPanel>

gerrit-gwtui/src/main/java/com/google/gerrit/client/change/FollowUpAction.java

@@ -0,0 +1,46 @@
+// Copyright (C) 2013 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.client.change;
+
+import com.google.gerrit.client.Gerrit;
+import com.google.gerrit.client.changes.ChangeApi;
+import com.google.gerrit.client.changes.ChangeInfo;
+import com.google.gerrit.client.rpc.GerritCallback;
+import com.google.gerrit.common.PageLinks;
+import com.google.gwt.user.client.ui.Button;
+
+class FollowUpAction extends ActionMessageBox {
+  private final String project;
+  private final String branch;
+  private final String base;
+
+  FollowUpAction(Button b, String project, String branch, String key) {
+    super(b);
+    this.project = project;
+    this.branch = branch;
+    this.base = project + "~" + branch + "~" + key;
+  }
+
+  void send(String message) {
+    ChangeApi.createChange(project, branch, message, base,
+        new GerritCallback<ChangeInfo>() {
+          @Override
+          public void onSuccess(ChangeInfo result) {
+            Gerrit.display(PageLinks.toChange(result.legacy_id()));
+            hide();
+          }
+        });
+  }
+}

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

@@ -36,11 +36,12 @@ public class ChangeApi {
 
   /** Create a new change. */
   public static void createChange(String project, String branch,
-      String subject, AsyncCallback<ChangeInfo> cb) {
+      String subject, String base, AsyncCallback<ChangeInfo> cb) {
     CreateChangeInput input = CreateChangeInput.create();
     input.project(emptyToNull(project));
     input.branch(emptyToNull(branch));
     input.subject(emptyToNull(subject));
+    input.base_change(emptyToNull(base));
 
     new RestApi("/changes/").post(input, cb);
   }
@@ -213,6 +214,7 @@ public class ChangeApi {
     public final native void branch(String b) /*-{ if(b)this.branch=b; }-*/;
     public final native void project(String p) /*-{ if(p)this.project=p; }-*/;
     public final native void subject(String s) /*-{ if(s)this.subject=s; }-*/;
+    public final native void base_change(String b) /*-{ if(b)this.base_change=b; }-*/;
 
     protected CreateChangeInput() {
     }

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

@@ -20,8 +20,10 @@ import static java.util.concurrent.TimeUnit.MINUTES;
 import static java.util.concurrent.TimeUnit.SECONDS;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.common.collect.ImmutableList;
 import com.google.common.primitives.Ints;
 import com.google.gerrit.common.errors.EmailException;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.ChangeMessage;
 import com.google.gerrit.reviewdb.client.PatchSet;
@@ -30,6 +32,7 @@ import com.google.gerrit.reviewdb.client.RevId;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.change.ChangeInserter;
 import com.google.gerrit.server.change.ChangeMessages;
+import com.google.gerrit.server.change.ChangeTriplet;
 import com.google.gerrit.server.change.PatchSetInserter;
 import com.google.gerrit.server.events.CommitReceivedEvent;
 import com.google.gerrit.server.extensions.events.GitReferenceUpdated;
@@ -516,6 +519,39 @@ public class ChangeUtil {
     db.patchSets().delete(Collections.singleton(patch));
   }
 
+  public List<Change> findChanges(String id)
+      throws OrmException, ResourceNotFoundException {
+    // Try legacy id
+    if (id.matches("^[1-9][0-9]*$")) {
+      Change c = db.get().changes().get(Change.Id.parse(id));
+      if (c != null) {
+        return ImmutableList.of(c);
+      }
+      return Collections.emptyList();
+    }
+
+    // Try isolated changeId
+    if (!id.contains("~")) {
+      Change.Key key = new Change.Key(id);
+      if (key.get().length() == 41) {
+        return db.get().changes().byKey(key).toList();
+      } else {
+        return db.get().changes().byKeyRange(key, key.max()).toList();
+      }
+    }
+
+    // Try change triplet
+    ChangeTriplet triplet;
+    try {
+        triplet = new ChangeTriplet(id);
+    } catch (ChangeTriplet.ParseException e) {
+        throw new ResourceNotFoundException(id);
+    }
+    return db.get().changes().byBranchKey(
+        triplet.getBranchNameKey(),
+        triplet.getChangeKey()).toList();
+  }
+
   private IdentifiedUser user() {
     return (IdentifiedUser) userProvider.get();
   }

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

@@ -62,6 +62,7 @@ import com.google.gerrit.extensions.config.DownloadScheme;
 import com.google.gerrit.extensions.registration.DynamicMap;
 import com.google.gerrit.extensions.restapi.RestView;
 import com.google.gerrit.extensions.restapi.Url;
+import com.google.gerrit.extensions.webui.PrivateInternals_UiActionDescription;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.reviewdb.client.Account;
 import com.google.gerrit.reviewdb.client.Change;
@@ -331,6 +332,14 @@ public class ChangeJson {
           userProvider)) {
         out.actions.put(d.getId(), new ActionInfo(d));
       }
+      if (userProvider.get().isIdentifiedUser()
+          && in.getStatus().isOpen()) {
+        UiAction.Description descr = new UiAction.Description();
+        PrivateInternals_UiActionDescription.setId(descr, "followup");
+        PrivateInternals_UiActionDescription.setMethod(descr, "POST");
+        descr.setTitle("Create follow-up change");
+        out.actions.put(descr.getId(), new ActionInfo(descr));
+      }
     }
     return out;
   }

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

@@ -14,7 +14,6 @@
 
 package com.google.gerrit.server.change;
 
-import com.google.common.collect.ImmutableList;
 import com.google.gerrit.extensions.registration.DynamicMap;
 import com.google.gerrit.extensions.restapi.AcceptsPost;
 import com.google.gerrit.extensions.restapi.IdString;
@@ -24,7 +23,7 @@ import com.google.gerrit.extensions.restapi.RestCollection;
 import com.google.gerrit.extensions.restapi.RestView;
 import com.google.gerrit.extensions.restapi.TopLevelResource;
 import com.google.gerrit.reviewdb.client.Change;
-import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.project.ChangeControl;
 import com.google.gerrit.server.project.NoSuchChangeException;
@@ -34,33 +33,32 @@ import com.google.inject.Inject;
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
 
-import java.util.Collections;
 import java.util.List;
 
 @Singleton
 public class ChangesCollection implements
     RestCollection<TopLevelResource, ChangeResource>,
     AcceptsPost<TopLevelResource> {
-  private final Provider<ReviewDb> db;
   private final Provider<CurrentUser> user;
   private final ChangeControl.GenericFactory changeControlFactory;
   private final Provider<QueryChanges> queryFactory;
   private final DynamicMap<RestView<ChangeResource>> views;
+  private final ChangeUtil changeUtil;
   private final CreateChange createChange;
 
   @Inject
   ChangesCollection(
-      Provider<ReviewDb> dbProvider,
       Provider<CurrentUser> user,
       ChangeControl.GenericFactory changeControlFactory,
       Provider<QueryChanges> queryFactory,
       DynamicMap<RestView<ChangeResource>> views,
+      ChangeUtil changeUtil,
       CreateChange createChange) {
-    this.db = dbProvider;
     this.user = user;
     this.changeControlFactory = changeControlFactory;
     this.queryFactory = queryFactory;
     this.views = views;
+    this.changeUtil = changeUtil;
     this.createChange = createChange;
   }
 
@@ -77,7 +75,7 @@ public class ChangesCollection implements
   @Override
   public ChangeResource parse(TopLevelResource root, IdString id)
       throws ResourceNotFoundException, OrmException {
-    List<Change> changes = findChanges(id.encoded());
+    List<Change> changes = changeUtil.findChanges(id.encoded());
     if (changes.size() != 1) {
       throw new ResourceNotFoundException(id);
     }
@@ -101,39 +99,6 @@ public class ChangesCollection implements
     return new ChangeResource(control);
   }
 
-  private List<Change> findChanges(String id)
-      throws OrmException, ResourceNotFoundException {
-    // Try legacy id
-    if (id.matches("^[1-9][0-9]*$")) {
-      Change c = db.get().changes().get(Change.Id.parse(id));
-      if (c != null) {
-        return ImmutableList.of(c);
-      }
-      return Collections.emptyList();
-    }
-
-    // Try isolated changeId
-    if (!id.contains("~")) {
-      Change.Key key = new Change.Key(id);
-      if (key.get().length() == 41) {
-        return db.get().changes().byKey(key).toList();
-      } else {
-        return db.get().changes().byKeyRange(key, key.max()).toList();
-      }
-    }
-
-    // Try change triplet
-    ChangeTriplet triplet;
-    try {
-        triplet = new ChangeTriplet(id);
-    } catch (ChangeTriplet.ParseException e) {
-        throw new ResourceNotFoundException(id);
-    }
-    return db.get().changes().byBranchKey(
-        triplet.getBranchNameKey(),
-        triplet.getChangeKey()).toList();
-  }
-
   @SuppressWarnings("unchecked")
   @Override
   public CreateChange post(TopLevelResource parent) throws RestApiException {

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

@@ -15,11 +15,13 @@
 package com.google.gerrit.server.change;
 
 import com.google.common.base.Strings;
+import com.google.common.collect.Iterables;
 import com.google.gerrit.common.data.Capable;
 import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.extensions.common.ChangeStatus;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.restapi.TopLevelResource;
@@ -29,6 +31,7 @@ import com.google.gerrit.reviewdb.client.Change;
 import com.google.gerrit.reviewdb.client.PatchSet;
 import com.google.gerrit.reviewdb.client.Project;
 import com.google.gerrit.reviewdb.server.ReviewDb;
+import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.GerritPersonIdent;
 import com.google.gerrit.server.IdentifiedUser;
@@ -80,6 +83,7 @@ public class CreateChange implements
   private final CommitValidators.Factory commitValidatorsFactory;
   private final ChangeInserter.Factory changeInserterFactory;
   private final ChangeJson json;
+  private final ChangeUtil changeUtil;
 
   @Inject
   CreateChange(Provider<ReviewDb> db,
@@ -89,7 +93,8 @@ public class CreateChange implements
       ProjectsCollection projectsCollection,
       CommitValidators.Factory commitValidatorsFactory,
       ChangeInserter.Factory changeInserterFactory,
-      ChangeJson json) {
+      ChangeJson json,
+      ChangeUtil changeUtil) {
     this.db = db;
     this.gitManager = gitManager;
     this.serverTimeZone = myIdent.getTimeZone();
@@ -98,13 +103,14 @@ public class CreateChange implements
     this.commitValidatorsFactory = commitValidatorsFactory;
     this.changeInserterFactory = changeInserterFactory;
     this.json = json;
+    this.changeUtil = changeUtil;
   }
 
   @Override
   public Response<ChangeJson.ChangeInfo> apply(TopLevelResource parent,
       ChangeInfo input) throws AuthException, OrmException,
       BadRequestException, UnprocessableEntityException, IOException,
-      InvalidChangeOperationException {
+      InvalidChangeOperationException, ResourceNotFoundException {
 
     if (Strings.isNullOrEmpty(input.project)) {
       throw new BadRequestException("project must be non-empty");
@@ -148,17 +154,32 @@ public class CreateChange implements
     try {
       RevWalk rw = new RevWalk(git);
       try {
-        Ref destRef = git.getRef(refName);
-        if (destRef == null) {
-          throw new UnprocessableEntityException(String.format(
-              "Branch %s does not exist.", refName));
+        ObjectId parentCommit;
+        if (input.baseChange != null) {
+          List<Change> changes = changeUtil.findChanges(input.baseChange);
+          if (changes.isEmpty()) {
+            throw new InvalidChangeOperationException(
+                "Base change not found: " + input.baseChange);
+          }
+          Change change = Iterables.getOnlyElement(changes);
+          PatchSet ps = db.get().patchSets().get(
+              new PatchSet.Id(change.getId(),
+              change.currentPatchSetId().get()));
+          parentCommit = ObjectId.fromString(ps.getRevision().get());
+        } else {
+          Ref destRef = git.getRef(refName);
+          if (destRef == null) {
+            throw new UnprocessableEntityException(String.format(
+                "Branch %s does not exist.", refName));
+          }
+          parentCommit = destRef.getObjectId();
         }
+        RevCommit mergeTip = rw.parseCommit(parentCommit);
 
         Timestamp now = TimeUtil.nowTs();
         IdentifiedUser me = (IdentifiedUser) userProvider.get();
         PersonIdent author = me.newCommitterIdent(now, serverTimeZone);
 
-        RevCommit mergeTip = rw.parseCommit(destRef.getObjectId());
         ObjectId id = ChangeIdUtil.computeChangeId(mergeTip.getTree(),
             mergeTip, author, author, input.subject);
         String commitMessage = ChangeIdUtil.insertId(input.subject, id);
@@ -169,7 +190,7 @@ public class CreateChange implements
             getChangeId(id, c),
             new Change.Id(db.get().nextChangeId()),
             me.getAccountId(),
-            new Branch.NameKey(project, destRef.getName()),
+            new Branch.NameKey(project, refName),
             now);
 
         ChangeInserter ins =