Merge pull request #9355 from mono/jstedfast-debugger-load-children-incrementally

[Debugger] Incrementally load new children rather than remove-all and…

4 files changed, 92 insertions, 47 deletions

diff --git a/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/LocalsPad.cs b/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/LocalsPad.cs
index 00e893bf9e..97cf84202a 100644
--- a/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/LocalsPad.cs
+++ b/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/LocalsPad.cs
@@ -25,12 +25,36 @@
 //
 //
 
+using System;
+
 using Mono.Debugging.Client;
 
 namespace MonoDevelop.Debugger
 {
 	public class LocalsPad : ObjectValuePad
 	{
+		static readonly bool EnableFakeNodes;
+
+		static LocalsPad ()
+		{
+			var env = Environment.GetEnvironmentVariable ("VSMAC_DEBUGGER_TESTING");
+
+			if (!string.IsNullOrEmpty (env)) {
+				var options = env.Split (new char [] { ',' });
+
+				for (int i = 0; i < options.Length; i++) {
+					var option = options[i].Trim ();
+
+					if (option == "fake-locals") {
+						EnableFakeNodes = true;
+						return;
+					}
+				}
+			}
+
+			EnableFakeNodes = false;
+		}
+
 		public LocalsPad ()
 		{
 			if (UseNewTreeView) {
@@ -41,7 +65,6 @@ namespace MonoDevelop.Debugger
 			}
 		}
 
-#if ADD_FAKE_NODES
 		void AddFakeNodes ()
 		{
 			var xx = new System.Collections.Generic.List<ObjectValueNode> ();
@@ -60,7 +83,6 @@ namespace MonoDevelop.Debugger
 
 			controller.AddValues (xx);
 		}
-#endif
 
 		void ReloadValues ()
 		{
@@ -84,9 +106,10 @@ namespace MonoDevelop.Debugger
 				} finally {
 					_treeview.EndUpdates ();
 				}
-#if ADD_FAKE_NODES
-				AddFakeNodes ();
-#endif
+
+
+				if (EnableFakeNodes)
+					AddFakeNodes ();
 			} else {
 				tree.ClearValues ();
 				tree.AddValues (locals);
diff --git a/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/Mac/MacObjectValueTreeView.cs b/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/Mac/MacObjectValueTreeView.cs
index defc2afe67..c3607d30e2 100644
--- a/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/Mac/MacObjectValueTreeView.cs
+++ b/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/Mac/MacObjectValueTreeView.cs
@@ -348,19 +348,13 @@ namespace MonoDevelop.Debugger
 
 		public override void ExpandItem (NSObject item, bool expandChildren)
 		{
-			NSAnimationContext.BeginGrouping ();
-			NSAnimationContext.CurrentContext.Duration = 0;
 			base.ExpandItem (item, expandChildren);
-			NSAnimationContext.EndGrouping ();
 			OptimizeColumnSizes ();
 		}
 
 		public override void ExpandItem (NSObject item)
 		{
-			NSAnimationContext.BeginGrouping ();
-			NSAnimationContext.CurrentContext.Duration = 0;
 			base.ExpandItem (item);
-			NSAnimationContext.EndGrouping ();
 			OptimizeColumnSizes ();
 		}
 
@@ -376,19 +370,13 @@ namespace MonoDevelop.Debugger
 
 		public override void CollapseItem (NSObject item, bool collapseChildren)
 		{
-			NSAnimationContext.BeginGrouping ();
-			NSAnimationContext.CurrentContext.Duration = 0;
 			base.CollapseItem (item, collapseChildren);
-			NSAnimationContext.EndGrouping ();
 			OptimizeColumnSizes ();
 		}
 
 		public override void CollapseItem (NSObject item)
 		{
-			NSAnimationContext.BeginGrouping ();
-			NSAnimationContext.CurrentContext.Duration = 0;
 			base.CollapseItem (item);
-			NSAnimationContext.EndGrouping ();
 			OptimizeColumnSizes ();
 		}
 
@@ -551,7 +539,7 @@ namespace MonoDevelop.Debugger
 			if (disposed)
 				return;
 
-			dataSource.ReloadChildren (node);
+			dataSource.LoadChildren (node, startIndex, count);
 			OptimizeColumnSizes ();
 		}
 
diff --git a/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/Mac/MacObjectValueTreeViewDataSource.cs b/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/Mac/MacObjectValueTreeViewDataSource.cs
index 8a4c282cfe..f3d89fd23f 100644
--- a/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/Mac/MacObjectValueTreeViewDataSource.cs
+++ b/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/Mac/MacObjectValueTreeViewDataSource.cs
@@ -89,7 +89,10 @@ namespace MonoDevelop.Debugger
 			var value = new MacObjectValueNode (parent, node);
 			mapping[node] = value;
 
-			parent.Children.Insert (index, value);
+			if (index < parent.Children.Count)
+				parent.Children.Insert (index, value);
+			else
+				parent.Children.Add (value);
 
 			if (treeView.AllowExpanding) {
 				foreach (var child in node.Children)
@@ -181,7 +184,7 @@ namespace MonoDevelop.Debugger
 				removed[i].Dispose ();
 		}
 
-		public void ReloadChildren (ObjectValueNode node)
+		public void LoadChildren (ObjectValueNode node, int startIndex, int count)
 		{
 			if (!TryGetValue (node, out var parent))
 				return;
@@ -189,36 +192,66 @@ namespace MonoDevelop.Debugger
 			treeView.BeginUpdates ();
 
 			try {
-				NSIndexSet indexes;
+				int lastIndex = parent.Children.Count - 1;
+				bool needShowMore = !node.ChildrenLoaded;
+				bool haveShowMore = false;
+				NSIndexSet indexes = null;
 				NSRange range;
 
-				if (parent.Children.Count > 0) {
-					range = new NSRange (0, parent.Children.Count);
-					indexes = NSIndexSet.FromNSRange (range);
+				if (lastIndex >= 0 && parent.Children[lastIndex].Target is ShowMoreValuesObjectValueNode)
+					haveShowMore = true;
 
+				if (startIndex < parent.Children.Count) {
+					// Note: This can only happen if we have either a "Loading..." node or a "Show More" node.
 					var removed = new List<MacObjectValueNode> ();
-					foreach (var child in parent.Children)
-						Remove (child, removed);
-
-					parent.Children.Clear ();
-
-					if (parent.Target is RootObjectValueNode)
-						treeView.RemoveItems (indexes, null, NSTableViewAnimation.None);
-					else
-						treeView.RemoveItems (indexes, parent, NSTableViewAnimation.None);
-
-					for (int i = 0; i < removed.Count; i++)
-						removed[i].Dispose ();
+					int extra = parent.Children.Count - startIndex;
+
+					if (lastIndex == 0 && parent.Children[0].Target is LoadingObjectValueNode) {
+						// Remove the "Loading..." node
+						indexes = NSIndexSet.FromIndex (0);
+						Remove (parent.Children[0], removed);
+						parent.Children.Clear ();
+					} else if (haveShowMore && extra == 1) {
+						// Only remove the "Show More" node if we don't need it anymore...
+						if (!needShowMore) {
+							indexes = NSIndexSet.FromIndex (lastIndex);
+							Remove (parent.Children[lastIndex], removed);
+							parent.Children.RemoveAt (lastIndex);
+						}
+					} else {
+						// Unexpected, but let's try to deal with this...
+						range = new NSRange (startIndex, extra);
+						indexes = NSIndexSet.FromNSRange (range);
+
+						for (int i = parent.Children.Count - 1; i >= startIndex; i--) {
+							Remove (parent.Children[i], removed);
+							parent.Children.RemoveAt (i);
+						}
+
+						haveShowMore = false;
+					}
+
+					if (indexes != null) {
+						if (parent.Target is RootObjectValueNode)
+							treeView.RemoveItems (indexes, null, NSTableViewAnimation.None);
+						else
+							treeView.RemoveItems (indexes, parent, NSTableViewAnimation.None);
+
+						for (int i = 0; i < removed.Count; i++)
+							removed[i].Dispose ();
+					}
 				}
 
-				for (int i = 0; i < node.Children.Count; i++)
-					Add (parent, node.Children[i]);
+				for (int i = startIndex; i < startIndex + count; i++)
+					Insert (parent, i, node.Children[i]);
 
-				// if we did not load all the children, add a Show More node
-				if (!node.ChildrenLoaded)
+				// Add a "Show More" node only if we need one and don't already have one.
+				if (needShowMore && !haveShowMore) {
 					Add (parent, new ShowMoreValuesObjectValueNode (node));
+					count++;
+				}
 
-				range = new NSRange (0, parent.Children.Count);
+				range = new NSRange (startIndex, count);
 				indexes = NSIndexSet.FromNSRange (range);
 
 				if (parent.Target is RootObjectValueNode)
diff --git a/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/ObjectValueTreeViewController.cs b/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/ObjectValueTreeViewController.cs
index 0183375d4f..614204b8cc 100644
--- a/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/ObjectValueTreeViewController.cs
+++ b/main/src/addins/MonoDevelop.Debugger/MonoDevelop.Debugger/ObjectValue/ObjectValueTreeViewController.cs
@@ -670,21 +670,22 @@ namespace MonoDevelop.Debugger
 
 			node.IsExpanded = true;
 
-			int loadedCount = 0;
+			int index = node.Children.Count;
+			int count = 0;
+
 			if (node.IsEnumerable) {
 				// if we already have some loaded, don't load more - that is a specific user gesture
-				if (node.Children.Count == 0) {
+				if (index == 0) {
 					// page the children in, instead of loading them all at once
-					loadedCount = await FetchChildrenAsync (node, MaxEnumerableChildrenToFetch, cancellationTokenSource.Token);
+					count = await FetchChildrenAsync (node, MaxEnumerableChildrenToFetch, cancellationTokenSource.Token);
 				}
 			} else {
-				loadedCount = await FetchChildrenAsync (node, 0, cancellationTokenSource.Token);
+				count = await FetchChildrenAsync (node, -1, cancellationTokenSource.Token);
 			}
 
 			await Runtime.RunInMainThread (() => {
 				// tell the view about the children, even if there are, in fact, none
-				view.LoadNodeChildren (node, 0, node.Children.Count);
-
+				view.LoadNodeChildren (node, index, count);
 				view.OnNodeExpanded (node);
 			});
 		}