[stagingView] Don't accept arbitrary drops

Previously, the staging view would stage the selected files, even when
an unrelated drop happened (by mistake), e.g. from a file from the
Package Explorer. The same with unstaging.

By checking that the event data is actually a StagingEntry (i.e. the
drag was started from the staging view), we ensure that no accidental
drops can cause staging.

Change-Id: Ida2f9fdb9653b015a0ce3d410b789cf65915de38
Signed-off-by: Robin Stocker <robin@nibor.org>

1 files changed, 10 insertions, 6 deletions

diff --git a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/staging/StagingView.java b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/staging/StagingView.java
index 0055b27808..6f00daf02e 100644
--- a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/staging/StagingView.java
+++ b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/staging/StagingView.java
@@ -376,9 +376,11 @@ public class StagingView extends ViewPart {
 				new Transfer[] { LocalSelectionTransfer.getTransfer() },
 				new DropTargetAdapter() {
 					public void drop(DropTargetEvent event) {
-						final IStructuredSelection selection = (IStructuredSelection) stagedTableViewer
-								.getSelection();
-						unstage(selection);
+						if (event.data instanceof IStructuredSelection) {
+							final IStructuredSelection selection = (IStructuredSelection) event.data;
+							if (selection.getFirstElement() instanceof StagingEntry)
+								unstage(selection);
+						}
 					}
 
 					public void dragOver(DropTargetEvent event) {
@@ -459,9 +461,11 @@ public class StagingView extends ViewPart {
 				new Transfer[] { LocalSelectionTransfer.getTransfer() },
 				new DropTargetAdapter() {
 					public void drop(DropTargetEvent event) {
-						final IStructuredSelection selection = (IStructuredSelection) unstagedTableViewer
-								.getSelection();
-						stage(selection);
+						if (event.data instanceof IStructuredSelection) {
+							final IStructuredSelection selection = (IStructuredSelection) event.data;
+							if (selection.getFirstElement() instanceof StagingEntry)
+								stage(selection);
+						}
 					}
 
 					public void dragOver(DropTargetEvent event) {