[DotNetCore] Show SDK information before dependencies are restored

Fixed bug #56455 - Show SDK for project when not restored
https://bugzilla.xamarin.com/show_bug.cgi?id=56455

When a new .NET Core project is created the Dependencies - SDK folder
shows no items until the restore is completed. Now the SDK dependency
is shown (e.g. NETStandard.Library or Microsoft.NETCore.App) whilst
the dependencies are being restored and the updated information has
not yet been returned from MSBuild. This mirrors the behaviour of
Visual Studio on Windows.

3 files changed, 32 insertions, 0 deletions

diff --git a/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/PackageDependencyNode.cs b/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/PackageDependencyNode.cs
index 8067bbfed0..a459ee357a 100644
--- a/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/PackageDependencyNode.cs
+++ b/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/PackageDependencyNode.cs
@@ -66,6 +66,18 @@ namespace MonoDevelop.DotNetCore.NodeBuilders
 			version = packageReference.Metadata.GetValue ("Version", string.Empty);
 		}
 
+		public PackageDependencyNode (
+			DependenciesNode dependenciesNode,
+			string name,
+			bool topLevel,
+			bool readOnly)
+		{
+			this.dependenciesNode = dependenciesNode;
+			this.name = name;
+			IsTopLevel = topLevel;
+			IsReadOnly = readOnly;
+		}
+
 		public static PackageDependencyNode Create (
 			DependenciesNode dependenciesNode,
 			string dependencyName,
@@ -111,6 +123,9 @@ namespace MonoDevelop.DotNetCore.NodeBuilders
 
 		public string GetSecondaryLabel ()
 		{
+			if (string.IsNullOrEmpty (version))
+				return string.Empty;
+
 			return string.Format ("({0})", version);
 		}
 
diff --git a/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/SdkDependenciesNode.cs b/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/SdkDependenciesNode.cs
index 57bd391991..137084bee9 100644
--- a/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/SdkDependenciesNode.cs
+++ b/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/SdkDependenciesNode.cs
@@ -78,5 +78,16 @@ namespace MonoDevelop.DotNetCore.NodeBuilders
 		{
 			return ParentNode.PackageDependencyCache.GetDependency (dependency);
 		}
+
+		/// <summary>
+		/// Returns a SDK node for the project whilst the package dependencies are still loading.
+		/// </summary>
+		public IEnumerable<PackageDependencyNode> GetDefaultNodes ()
+		{
+			if (Project.TargetFramework.IsNetCoreApp ())
+				yield return new PackageDependencyNode (ParentNode, "Microsoft.NETCore.App", true, true);
+			else if (Project.TargetFramework.IsNetStandard ())
+				yield return new PackageDependencyNode (ParentNode, "NETStandard.Library", true, true);
+		}
 	}
 }
diff --git a/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/SdkDependenciesNodeBuilder.cs b/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/SdkDependenciesNodeBuilder.cs
index 2f6878cb38..305b59f2d2 100644
--- a/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/SdkDependenciesNodeBuilder.cs
+++ b/main/src/addins/MonoDevelop.DotNetCore/MonoDevelop.DotNetCore.NodeBuilders/SdkDependenciesNodeBuilder.cs
@@ -62,6 +62,8 @@ namespace MonoDevelop.DotNetCore.NodeBuilders
 			var dependenciesNode = (SdkDependenciesNode)dataObject;
 			if (dependenciesNode.LoadedDependencies) {
 				AddLoadedDependencyNodes (treeBuilder, dependenciesNode);
+			} else {
+				treeBuilder.AddChildren (dependenciesNode.GetDefaultNodes ());
 			}
 		}
 
@@ -73,6 +75,10 @@ namespace MonoDevelop.DotNetCore.NodeBuilders
 			} else if (frameworkNodes.Any ()) {
 				var frameworkNode = frameworkNodes.First ();
 				treeBuilder.AddChildren (frameworkNode.GetDependencyNodes ());
+			} else {
+				// Projects sometimes return no dependencies from MSBuild initially so
+				// add the default nodes until the dependencies are updated.
+				treeBuilder.AddChildren (dependenciesNode.GetDefaultNodes ());
 			}
 		}