[vcs]: getVcsRoot quick for branch widget (IDEA-144935 Blocking EDT waiting for git command)

* update widgets when mappings changes, not only one repository info changed
* add repository mappings changed topic to track when Repositories are already constructed and added to common VcsRepositoryManager storage;
* add appropriate Dvcs common repo mapping listener

platform/dvcs-impl/src/com/intellij/dvcs/DvcsUtil.java

@@ -16,6 +16,7 @@
 package com.intellij.dvcs;
 
 import com.intellij.dvcs.push.PushSupport;
+import com.intellij.dvcs.repo.AbstractRepositoryManager;
 import com.intellij.dvcs.repo.RepoStateException;
 import com.intellij.dvcs.repo.Repository;
 import com.intellij.dvcs.repo.RepositoryManager;
@@ -275,6 +276,15 @@ public class DvcsUtil {
     return repository != null ? repository : manager.getRepositoryForRoot(guessRootForVcs(project, vcs, defaultRootPathValue));
   }
 
+  @Nullable
+  public static <T extends Repository> T guessCurrentRepositoryQuick(@NotNull Project project,
+                                                                     @NotNull AbstractRepositoryManager<T> manager,
+                                                                     @Nullable String defaultRootPathValue) {
+    T repository = manager.getRepositoryForRootQuick(guessVcsRoot(project, getSelectedFile(project)));
+    return repository != null ? repository
+                              : manager.getRepositoryForRootQuick(guessRootForVcs(project, manager.getVcs(), defaultRootPathValue));
+  }
+
   @Nullable
   private static VirtualFile guessRootForVcs(@NotNull Project project, @Nullable AbstractVcs vcs, @Nullable String defaultRootPathValue) {
     if (project.isDisposed()) return null;

platform/dvcs-impl/src/com/intellij/dvcs/repo/AbstractRepositoryManager.java

@@ -105,4 +105,10 @@ public abstract class AbstractRepositoryManager<T extends Repository>
     //noinspection unchecked
     return vcsDir != null && vcsDir.exists() ? (T)repository : null;
   }
+
+  @NotNull
+  public AbstractVcs getVcs() {
+    return myVcs;
+  }
+
 }

platform/dvcs-impl/src/com/intellij/dvcs/repo/VcsRepositoryManager.java

@@ -30,6 +30,7 @@ import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.util.ArrayUtil;
 import com.intellij.util.ObjectUtils;
 import com.intellij.util.containers.ContainerUtil;
+import com.intellij.util.messages.Topic;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -41,6 +42,10 @@ import java.util.concurrent.locks.ReentrantReadWriteLock;
  * extension point in a thread safe way.
  */
 public class VcsRepositoryManager extends AbstractProjectComponent implements Disposable, VcsListener {
+
+  public static final Topic<VcsRepositoryMappingListener> VCS_REPOSITORY_MAPPING_UPDATED =
+    Topic.create("VCS repository mapping updated", VcsRepositoryMappingListener.class);
+
   @NotNull private final ProjectLevelVcsManager myVcsManager;
 
   @NotNull private final ReentrantReadWriteLock REPO_LOCK = new ReentrantReadWriteLock();
@@ -204,6 +209,7 @@ public class VcsRepositoryManager extends AbstractProjectComponent implements Di
       finally {
         REPO_LOCK.writeLock().unlock();
       }
+      myProject.getMessageBus().syncPublisher(VCS_REPOSITORY_MAPPING_UPDATED).mappingChanged();
     }
     finally {
       MODIFY_LOCK.unlock();

platform/dvcs-impl/src/com/intellij/dvcs/repo/VcsRepositoryMappingListener.java

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * 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.intellij.dvcs.repo;
+
+public interface VcsRepositoryMappingListener {
+
+  void mappingChanged();
+}

platform/dvcs-impl/src/com/intellij/dvcs/ui/DvcsStatusWidget.java

@@ -16,6 +16,8 @@
 package com.intellij.dvcs.ui;
 
 import com.intellij.dvcs.repo.Repository;
+import com.intellij.dvcs.repo.VcsRepositoryManager;
+import com.intellij.dvcs.repo.VcsRepositoryMappingListener;
 import com.intellij.openapi.application.ApplicationManager;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.fileEditor.FileEditorManager;
@@ -200,6 +202,7 @@ public abstract class DvcsStatusWidget<T extends Repository> extends EditorBased
         StatusBar statusBar = WindowManager.getInstance().getStatusBar(project);
         if (statusBar != null && !isDisposed()) {
           statusBar.addWidget(widget, "after " + (SystemInfo.isMac ? "Encoding" : "InsertOverwrite"), project);
+          subscribeToMappingChanged();
           subscribeToRepoChangeEvents(project);
           update();
         }
@@ -218,4 +221,14 @@ public abstract class DvcsStatusWidget<T extends Repository> extends EditorBased
       }
     });
   }
+
+  private void subscribeToMappingChanged() {
+    myProject.getMessageBus().connect().subscribe(VcsRepositoryManager.VCS_REPOSITORY_MAPPING_UPDATED, new VcsRepositoryMappingListener() {
+      @Override
+      public void mappingChanged() {
+        LOG.debug("repository mappings changed");
+        updateLater();
+      }
+    });
+  }
 }

plugins/git4idea/src/git4idea/ui/branch/GitBranchWidget.java

@@ -15,6 +15,7 @@
  */
 package git4idea.ui.branch;
 
+import com.intellij.dvcs.DvcsUtil;
 import com.intellij.dvcs.ui.DvcsStatusWidget;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.ui.popup.ListPopup;
@@ -47,7 +48,7 @@ public class GitBranchWidget extends DvcsStatusWidget<GitRepository> {
   @Nullable
   @Override
   protected GitRepository guessCurrentRepository(@NotNull Project project) {
-    return GitBranchUtil.getCurrentRepository(project);
+    return DvcsUtil.guessCurrentRepositoryQuick(project, GitUtil.getRepositoryManager(project), mySettings.getRecentRootPath());
   }
 
   @NotNull

plugins/hg4idea/src/org/zmlx/hg4idea/status/ui/HgStatusWidget.java

@@ -15,6 +15,7 @@
  */
 package org.zmlx.hg4idea.status.ui;
 
+import com.intellij.dvcs.DvcsUtil;
 import com.intellij.dvcs.ui.DvcsStatusWidget;
 import com.intellij.openapi.project.Project;
 import com.intellij.openapi.ui.popup.ListPopup;
@@ -52,7 +53,8 @@ public class HgStatusWidget extends DvcsStatusWidget<HgRepository> {
   @Nullable
   @Override
   protected HgRepository guessCurrentRepository(@NotNull Project project) {
-    return HgUtil.getCurrentRepository(project);
+    return DvcsUtil.guessCurrentRepositoryQuick(project, HgUtil.getRepositoryManager(project),
+                                                HgProjectSettings.getInstance(project).getRecentRootPath());
   }
 
   @NotNull