Compute visualizer graph layout in the language server (MSAGL)

src/Bicep.LangServer.IntegrationTests/Features/Visualization/VisualGraphUpdateTests.cs

@@ -26,7 +26,7 @@ public class VisualGraphUpdateTests
         public TestContext? TestContext { get; set; }
 
         [TestMethod]
-        public async Task Initial_request_with_null_current_returns_a_full_add_delta()
+        public async Task VisualGraphUpdate_ForNullCurrent_ReturnsFullAddDelta()
         {
             using var helper = await StartServerAndOpenAsync();
             var client = helper.Helper.Client;
@@ -60,11 +60,12 @@ public async Task Initial_request_with_null_current_returns_a_full_add_delta()
             result.Patches.OfType<GraphPatch.RemoveNode>().Should().BeEmpty();
             result.Patches.OfType<GraphPatch.RemoveEdge>().Should().BeEmpty();
             result.Patches.OfType<GraphPatch.UpdateNode>().Should().BeEmpty();
+            result.Patches.OfType<GraphPatch.SetNodeLayout>().Should().BeEmpty();
             result.Patches.OfType<GraphPatch.SetErrorCount>().Single().ErrorCount.Should().Be(0);
         }
 
         [TestMethod]
-        public async Task Request_with_matching_current_returns_only_metadata_refresh()
+        public async Task VisualGraphUpdate_ForMatchingCurrent_ReturnsOnlyMetadataRefresh()
         {
             using var helper = await StartServerAndOpenAsync();
             var client = helper.Helper.Client;
@@ -92,11 +93,61 @@ public async Task Request_with_matching_current_returns_only_metadata_refresh()
             result.Patches.OfType<GraphPatch.RemoveNode>().Should().BeEmpty();
             result.Patches.OfType<GraphPatch.AddEdge>().Should().BeEmpty();
             result.Patches.OfType<GraphPatch.RemoveEdge>().Should().BeEmpty();
+            result.Patches.OfType<GraphPatch.SetNodeLayout>().Should().BeEmpty();
             result.Patches.OfType<GraphPatch.UpdateNode>().Select(patch => patch.NodeId)
                 .Should().BeEquivalentTo("res1", "res2", "mod1", "mod1::res3");
             result.Patches.OfType<GraphPatch.SetErrorCount>().Single().ErrorCount.Should().Be(0);
         }
 
+        [TestMethod]
+        public async Task VisualGraphLayout_ForMeasuredMatchingCurrent_ReturnsLayoutPatches()
+        {
+            using var helper = await StartServerAndOpenAsync();
+            var client = helper.Helper.Client;
+
+            var initial = await client.SendRequest(
+                new VisualGraphUpdateParams(new TextDocumentIdentifier(helper.MainUri), Current: null),
+                default);
+
+            var renderedNodes = initial.Patches.OfType<GraphPatch.AddNode>()
+                .Select(patch => new RenderedGraphNode(patch.Node.Id, patch.Node.Kind, patch.Node.ParentId, 180, 72))
+                .ToList();
+            var renderedEdges = initial.Patches.OfType<GraphPatch.AddEdge>()
+                .Select(patch => new RenderedGraphEdge(patch.Edge.Id, patch.Edge.SourceId, patch.Edge.TargetId))
+                .ToList();
+
+            var result = await client.SendRequest(
+                new VisualGraphLayoutParams(
+                    new TextDocumentIdentifier(helper.MainUri),
+                    new RenderedGraph(renderedNodes, renderedEdges),
+                    Options: null),
+                default);
+
+            result.Status.Should().Be(VisualGraphLayoutStatus.Ok);
+            result.Patches.Should().AllBeOfType<GraphPatch.SetNodeLayout>();
+            result.Patches.OfType<GraphPatch.SetNodeLayout>().Select(patch => patch.NodeId)
+                .Should().BeEquivalentTo("res1", "res2", "mod1", "mod1::res3");
+            result.Patches.OfType<GraphPatch.SetNodeLayout>().Select(patch => patch.Layout)
+                .Should().OnlyContain(layout => double.IsFinite(layout.X) && double.IsFinite(layout.Y));
+        }
+
+        [TestMethod]
+        public async Task VisualGraphLayout_ForStaleMeasuredCurrent_ReturnsGraphChanged()
+        {
+            using var helper = await StartServerAndOpenAsync();
+            var client = helper.Helper.Client;
+            var stale = new RenderedGraph(
+                Nodes: [new RenderedGraphNode("missing", GraphNodeKind.Resource, ParentId: null, Width: 180, Height: 72)],
+                Edges: []);
+
+            var result = await client.SendRequest(
+                new VisualGraphLayoutParams(new TextDocumentIdentifier(helper.MainUri), stale, Options: null),
+                default);
+
+            result.Status.Should().Be(VisualGraphLayoutStatus.GraphChanged);
+            result.Patches.Should().BeEmpty();
+        }
+
         private async Task<TestServer> StartServerAndOpenAsync()
         {
             var diagnosticsListener = new MultipleMessageListener<PublishDiagnosticsParams>();

src/Bicep.LangServer.UnitTests/Features/Visualization/GraphPatchSerializationTests.cs

@@ -28,7 +28,7 @@ private static GraphPatch Deserialize(JToken token) =>
         token.ToObject<GraphPatch>(Serializer) ?? throw new InvalidOperationException("Deserialization returned null.");
 
     [TestMethod]
-    public void ClearGraph_round_trips_and_emits_camelCase_op()
+    public void ClearGraph_WhenSerialized_RoundTripsWithCamelCaseOp()
     {
         var patch = new GraphPatch.ClearGraph();
 
@@ -39,7 +39,7 @@ public void ClearGraph_round_trips_and_emits_camelCase_op()
     }
 
     [TestMethod]
-    public void AddNode_round_trips_with_camelCase_fields()
+    public void AddNode_WhenSerialized_RoundTripsWithCamelCaseFields()
     {
         var node = new GraphNode(
             Id: "res:foo",
@@ -62,7 +62,7 @@ public void AddNode_round_trips_with_camelCase_fields()
     }
 
     [TestMethod]
-    public void RemoveNode_round_trips()
+    public void RemoveNode_WhenSerialized_RoundTrips()
     {
         var patch = new GraphPatch.RemoveNode("res:foo");
 
@@ -74,7 +74,7 @@ public void RemoveNode_round_trips()
     }
 
     [TestMethod]
-    public void UpdateNode_round_trips_with_partial_changes()
+    public void UpdateNode_WithPartialChanges_RoundTrips()
     {
         var patch = new GraphPatch.UpdateNode("res:foo", new GraphNodeChanges(HasError: true));
 
@@ -85,7 +85,7 @@ public void UpdateNode_round_trips_with_partial_changes()
     }
 
     [TestMethod]
-    public void AddEdge_round_trips()
+    public void AddEdge_WhenSerialized_RoundTrips()
     {
         var patch = new GraphPatch.AddEdge(new GraphEdge("e1", "res:a", "res:b"));
 
@@ -96,7 +96,7 @@ public void AddEdge_round_trips()
     }
 
     [TestMethod]
-    public void RemoveEdge_round_trips()
+    public void RemoveEdge_WhenSerialized_RoundTrips()
     {
         var patch = new GraphPatch.RemoveEdge("e1");
 
@@ -108,7 +108,7 @@ public void RemoveEdge_round_trips()
     }
 
     [TestMethod]
-    public void SetNodeLayout_round_trips()
+    public void SetNodeLayout_WhenSerialized_RoundTrips()
     {
         var patch = new GraphPatch.SetNodeLayout("res:foo", new NodeLayout(12.5, -3.25));
 
@@ -119,7 +119,7 @@ public void SetNodeLayout_round_trips()
     }
 
     [TestMethod]
-    public void SetErrorCount_round_trips_with_camelCase_op()
+    public void SetErrorCount_WhenSerialized_RoundTripsWithCamelCaseOp()
     {
         var patch = new GraphPatch.SetErrorCount(3);
 
@@ -131,7 +131,7 @@ public void SetErrorCount_round_trips_with_camelCase_op()
     }
 
     [TestMethod]
-    public void Unknown_op_throws()
+    public void Deserialize_WithUnknownOp_Throws()
     {
         var json = new JObject { ["op"] = "bogus" };