From 591b2da171452f29bf2e379a2eb03142cf0a535a Mon Sep 17 00:00:00 2001
From: Thomas Wolf <thomas.wolf@paranor.ch>
Date: Sat, 4 Feb 2017 14:15:50 +0100
Subject: [PATCH] Remove the default handler for the checkout command in
 CommitEditor

Provide a dedicated handler with an appropriate activeWhen clause
instead. Somehow handler activation expressions are not properly
re-evaluated for these CommitEditor commands; seems to have
something to do with them being used in the header of a
SharedHeaderFormEditor. Add a PartListener to the CommitEditor that
forces an update of the toolbar on activations.

Bug: 495064
Bug: 511635
Change-Id: I8086b4ec328fb6b4eaa63a6f3b68ca0b075c5866
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
---
 org.eclipse.egit.ui/plugin.xml                     | 12 ++++-
 .../egit/ui/internal/commit/CommitEditor.java      | 63 +++++++++++++++++++++-
 2 files changed, 73 insertions(+), 2 deletions(-)

diff --git a/org.eclipse.egit.ui/plugin.xml b/org.eclipse.egit.ui/plugin.xml
index fbab05a62..076eb5b50 100644
--- a/org.eclipse.egit.ui/plugin.xml
+++ b/org.eclipse.egit.ui/plugin.xml
@@ -2410,6 +2410,17 @@
             </and>
          </activeWhen>
       </handler>
+      <handler
+            commandId="org.eclipse.egit.ui.commit.Checkout">
+         <class
+               class="org.eclipse.egit.ui.internal.commit.command.CheckoutHandler">
+         </class>
+         <activeWhen>
+            <with variable="activePart">
+               <instanceof value="org.eclipse.egit.ui.internal.commit.CommitEditor" />
+            </with>
+         </activeWhen>
+      </handler>
    </extension>
    <extension
          point="org.eclipse.ui.views">
@@ -5966,7 +5977,6 @@
             name="%CreateBranchCommand">
       </command>
       <command
-            defaultHandler="org.eclipse.egit.ui.internal.commit.command.CheckoutHandler"
             id="org.eclipse.egit.ui.commit.Checkout"
             name="%CheckoutCommand">
       </command>
diff --git a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/commit/CommitEditor.java b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/commit/CommitEditor.java
index 7cc1117ac..230b668e3 100644
--- a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/commit/CommitEditor.java
+++ b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/commit/CommitEditor.java
@@ -32,6 +32,7 @@ import org.eclipse.egit.ui.internal.commit.command.StashDropHandler;
 import org.eclipse.egit.ui.internal.repository.RepositoriesView;
 import org.eclipse.jface.action.ContributionManager;
 import org.eclipse.jface.action.ControlContribution;
+import org.eclipse.jface.action.IContributionItem;
 import org.eclipse.jface.action.IToolBarManager;
 import org.eclipse.jface.action.ToolBarManager;
 import org.eclipse.jface.resource.JFaceResources;
@@ -54,6 +55,9 @@ import org.eclipse.ui.IEditorActionBarContributor;
 import org.eclipse.ui.IEditorInput;
 import org.eclipse.ui.IEditorPart;
 import org.eclipse.ui.IEditorSite;
+import org.eclipse.ui.IPartListener;
+import org.eclipse.ui.IPartService;
+import org.eclipse.ui.IWorkbenchPart;
 import org.eclipse.ui.PartInitException;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.forms.IFormColors;
@@ -156,6 +160,48 @@ public class CommitEditor extends SharedHeaderFormEditor implements
 
 	private FocusTracker headerFocusTracker = new FocusTracker();
 
+	private IToolBarManager toolbar;
+
+	/** Ensures that the toolbar buttons in the header are properly updated. */
+	private IPartListener activationListener = new IPartListener() {
+
+		private boolean isActive;
+
+		@Override
+		public void partActivated(IWorkbenchPart part) {
+			if (part == CommitEditor.this) {
+				if (!isActive) {
+					isActive = true;
+					updateToolbar();
+				}
+			} else if (isActive) {
+				isActive = false;
+				updateToolbar();
+			}
+		}
+
+		@Override
+		public void partBroughtToTop(IWorkbenchPart part) {
+			// Nothing to do
+		}
+
+		@Override
+		public void partClosed(IWorkbenchPart part) {
+			// Nothing to do
+		}
+
+		@Override
+		public void partDeactivated(IWorkbenchPart part) {
+			// Nothing to do
+		}
+
+		@Override
+		public void partOpened(IWorkbenchPart part) {
+			// Nothing to do
+		}
+
+	};
+
 	private static class CommitEditorNestedSite extends MultiPageEditorSite {
 
 		public CommitEditorNestedSite(CommitEditor topLevelEditor,
@@ -238,7 +284,7 @@ public class CommitEditor extends SharedHeaderFormEditor implements
 		form.setToolTipText(commitName);
 		getToolkit().decorateFormHeading(form.getForm());
 
-		IToolBarManager toolbar = form.getToolBarManager();
+		toolbar = form.getToolBarManager();
 
 		ControlContribution repositoryLabelControl = new ControlContribution(
 				"repositoryLabel") { //$NON-NLS-1$
@@ -287,6 +333,8 @@ public class CommitEditor extends SharedHeaderFormEditor implements
 			}
 		};
 		toolbar.add(repositoryLabelControl);
+		CommonUtils.getService(getSite(), IPartService.class)
+				.addPartListener(activationListener);
 		if (commit.isStash()) {
 			toolbar.add(createCommandContributionItem(StashApplyHandler.ID));
 			toolbar.add(createCommandContributionItem(StashDropHandler.ID));
@@ -332,6 +380,17 @@ public class CommitEditor extends SharedHeaderFormEditor implements
 		}
 	}
 
+	private void updateToolbar() {
+		if (toolbar != null) {
+			// isEnabled() on a CommandContributionItem actually re-evaluates
+			// the enablement.
+			for (IContributionItem item : toolbar.getItems()) {
+				item.isEnabled();
+			}
+			toolbar.update(true);
+		}
+	}
+
 	private String getFormattedHeaderTitle(String commitName) {
 		if (getCommit().isStash()) {
 			int stashIndex = getStashIndex(getCommit().getRepository(),
@@ -411,6 +470,8 @@ public class CommitEditor extends SharedHeaderFormEditor implements
 
 	@Override
 	public void dispose() {
+		CommonUtils.getService(getSite(), IPartService.class)
+				.removePartListener(activationListener);
 		refListenerHandle.remove();
 		headerFocusTracker.dispose();
 		super.dispose();
-- 
2.11.4.GIT