Added some tests which cover a few end to end sceanrios

Author: jaredpar

src/Microsoft.DotNet.CodeFormatting.Tests/Microsoft.DotNet.CodeFormatting.Tests.csproj

@@ -106,6 +106,7 @@
   <ItemGroup>
     <Compile Include="CodeFormattingTestBase.cs" />
     <Compile Include="Rules\BracesRuleTests.cs" />
+    <Compile Include="Rules\CombinationTest.cs" />
     <Compile Include="Rules\ExplicitThisRuleTests.cs" />
     <Compile Include="Rules\ExplicitVisibilityRuleTests.cs" />
     <Compile Include="Rules\HasNewLineBeforeFirstNamespaceFormattingRuleTests.cs" />

src/Microsoft.DotNet.CodeFormatting.Tests/Rules/CombinationTest.cs

@@ -0,0 +1,85 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.CodeAnalysis;
+using Xunit;
+
+namespace Microsoft.DotNet.CodeFormatting.Tests
+{
+    /// <summary>
+    /// A test which runs all rules on a given piece of code 
+    /// </summary>
+    public sealed class CombinationTest : CodeFormattingTestBase
+    {
+        private static FormattingEngineImplementation s_formattingEngine;
+
+        static CombinationTest()
+        {
+            s_formattingEngine = (FormattingEngineImplementation)FormattingEngine.Create(Enumerable.Empty<string>(), Enumerable.Empty<string>());
+        }
+
+        protected override async Task<Document> RewriteDocumentAsync(Document document)
+        {
+            var solution = await s_formattingEngine.FormatCoreAsync(
+                document.Project.Solution,
+                new[] { document.Id },
+                CancellationToken.None);
+            return solution.GetDocument(document.Id);
+        }
+
+        [Fact]
+        public void FieldUse()
+        {
+            var text = @"
+class C {
+    int field;
+
+    void M() {
+        N(this.field);
+    }
+}";
+
+            var expected = @"
+internal class C
+{
+    private int _field;
+
+    private void M()
+    {
+        N(_field);
+    }
+}";
+
+            Verify(text, expected, runFormatter: false);
+        }
+
+        [Fact]
+        public void FieldAssignment()
+        {
+            var text = @"
+class C {
+    int field;
+
+    void M() {
+        this.field = 42;
+    }
+}";
+
+            var expected = @"
+internal class C
+{
+    private int _field;
+
+    private void M()
+    {
+        _field = 42;
+    }
+}";
+
+            Verify(text, expected, runFormatter: false);
+        }
+    }
+}

src/Microsoft.DotNet.CodeFormatting/Filters/IgnoreDesignerGeneratedCodeFilter.cs

@@ -14,6 +14,11 @@ internal sealed class IgnoreDesignerGeneratedCodeFilter : IFormattingFilter
     {
         public Task<bool> ShouldBeProcessedAsync(Document document)
         {
+            if (document.FilePath == null)
+            {
+                return Task.FromResult(true);
+            }
+
             var isDesignerGenerated = document.FilePath.EndsWith(".Designer.cs", StringComparison.OrdinalIgnoreCase);
             return Task.FromResult(!isDesignerGenerated);
         }

src/Microsoft.DotNet.CodeFormatting/FormattingEngineImplementation.cs

@@ -63,15 +63,21 @@ private async Task FormatAsync(Workspace workspace, IReadOnlyList<DocumentId> do
             watch.Start();
 
             var originalSolution = workspace.CurrentSolution;
+            var solution = await FormatCoreAsync(originalSolution, documentIds, cancellationToken);
+
+            watch.Stop();
+
+            await SaveChanges(solution, originalSolution, cancellationToken);
+            Console.WriteLine("Total time {0}", watch.Elapsed);
+        }
+
+        internal async Task<Solution> FormatCoreAsync(Solution originalSolution, IReadOnlyList<DocumentId> documentIds, CancellationToken cancellationToken)
+        {
             var solution = originalSolution;
             solution = await RunSyntaxPass(solution, documentIds, cancellationToken);
             solution = await RunLocalSemanticPass(solution, documentIds, cancellationToken);
             solution = await RunGlobalSemanticPass(solution, documentIds, cancellationToken);
-
-            await SaveChanges(solution, originalSolution, cancellationToken);
-
-            watch.Stop();
-            Console.WriteLine("Total time {0}", watch.Elapsed);
+            return solution;
         }
 
         private async Task SaveChanges(Solution solution, Solution originalSolution, CancellationToken cancellationToken)