From e353b08e8fdbe6ef3af24917f0c556413a1e6c26 Mon Sep 17 00:00:00 2001
From: Tanay Parikh <TanayParikh@users.noreply.github.com>
Date: Wed, 19 Aug 2020 14:52:03 -0700
Subject: [PATCH] Fix Add Using Added to Wrong Line (#2414)

* Fix Add Using Added to Wrong Line

Fixes: https://github.com/dotnet/aspnetcore/issues/25019

* PR Feedback
---
 .../AddUsingsCodeActionResolver.cs            |  3 +-
 .../RazorLanguageServer.cs                    |  2 +-
 .../AddUsingsCodeActionResolverTest.cs        | 36 ++++++++++++++++++-
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/CodeActions/AddUsingsCodeActionResolver.cs b/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/CodeActions/AddUsingsCodeActionResolver.cs
index 53bbb6e86c3..eb420367736 100644
--- a/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/CodeActions/AddUsingsCodeActionResolver.cs
+++ b/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/CodeActions/AddUsingsCodeActionResolver.cs
@@ -157,8 +157,9 @@ private static WorkspaceEditDocumentChange GenerateSingleUsingEditsAtTop(
             VersionedTextDocumentIdentifier codeDocumentIdentifier,
             string newUsingNamespace)
         {
+            var head = new Position(0, 0);
+
             // If we don't have usings, insert after the last namespace or page directive, which ever comes later
-            var head = new Position(1, 0);
             var syntaxTreeRoot = codeDocument.GetSyntaxTree().Root;
             var lastNamespaceOrPageDirective = syntaxTreeRoot
                 .DescendantNodes()
diff --git a/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/RazorLanguageServer.cs b/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/RazorLanguageServer.cs
index 3c7f2d39de2..5e532977bc3 100644
--- a/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/RazorLanguageServer.cs
+++ b/src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/RazorLanguageServer.cs
@@ -63,7 +63,7 @@ public static Task<RazorLanguageServer> CreateAsync(Stream input, Stream output,
             Serializer.Instance.JsonSerializer.Converters.RegisterRazorConverters();
 
             // Custom ClientCapabilities deserializer to extract experimental capabilities
-            Serializer.Instance.JsonSerializer.Converters.Add(ExtendableClientCapabilitiesJsonConverter.Instance);
+            // Serializer.Instance.JsonSerializer.Converters.Add(ExtendableClientCapabilitiesJsonConverter.Instance);
 
             ILanguageServer server = null;
             server = OmniSharp.Extensions.LanguageServer.Server.LanguageServer.PreInit(options =>
diff --git a/src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/CodeActions/AddUsingsCodeActionResolverTest.cs b/src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/CodeActions/AddUsingsCodeActionResolverTest.cs
index 88bdd8fccf1..56afa9329b7 100644
--- a/src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/CodeActions/AddUsingsCodeActionResolverTest.cs
+++ b/src/Razor/test/Microsoft.AspNetCore.Razor.LanguageServer.Test/CodeActions/AddUsingsCodeActionResolverTest.cs
@@ -116,7 +116,7 @@ public async Task Handle_AddOneUsingToEmpty()
             Assert.True(addUsingsChange.IsTextDocumentEdit);
             Assert.Single(addUsingsChange.TextDocumentEdit.Edits);
             var firstEdit = addUsingsChange.TextDocumentEdit.Edits.First();
-            Assert.Equal(1, firstEdit.Range.Start.Line);
+            Assert.Equal(0, firstEdit.Range.Start.Line);
             Assert.Equal($"@using System{Environment.NewLine}", firstEdit.NewText);
         }
 
@@ -154,6 +154,40 @@ public async Task Handle_AddOneUsingToPage()
             Assert.Equal($"@using System{Environment.NewLine}", firstEdit.NewText);
         }
 
+        [Fact]
+        public async Task Handle_AddOneUsingToHTML()
+        {
+            // Arrange
+            var documentPath = "c:/Test.razor";
+            var documentUri = new Uri(documentPath);
+            var contents = $"<table>{Environment.NewLine}<tr>{Environment.NewLine}</tr>{Environment.NewLine}</table>";
+            var codeDocument = CreateCodeDocument(contents);
+
+            var resolver = new AddUsingsCodeActionResolver(new DefaultForegroundDispatcher(), CreateDocumentResolver(documentPath, codeDocument));
+            var actionParams = new AddUsingsCodeActionParams
+            {
+                Uri = documentUri,
+                Namespace = "System"
+            };
+            var data = JObject.FromObject(actionParams);
+
+            // Act
+            var workspaceEdit = await resolver.ResolveAsync(data, default);
+
+            // Assert
+            Assert.NotNull(workspaceEdit);
+            Assert.NotNull(workspaceEdit.DocumentChanges);
+            Assert.Single(workspaceEdit.DocumentChanges);
+
+            var documentChanges = workspaceEdit.DocumentChanges.ToArray();
+            var addUsingsChange = documentChanges[0];
+            Assert.True(addUsingsChange.IsTextDocumentEdit);
+            Assert.Single(addUsingsChange.TextDocumentEdit.Edits);
+            var firstEdit = addUsingsChange.TextDocumentEdit.Edits.First();
+            Assert.Equal(0, firstEdit.Range.Start.Line);
+            Assert.Equal($"@using System{Environment.NewLine}", firstEdit.NewText);
+        }
+
         [Fact]
         public async Task Handle_AddOneUsingToNamespace()
         {