Moved from Renderer to Writer

src/Microsoft.AspNetCore.Razor.Evolution/CodeGeneration/DefaultDocumentWriter.cs

@@ -183,6 +183,11 @@ namespace Microsoft.AspNetCore.Razor.Evolution.CodeGeneration
                 Context.BasicWriter.WriteCSharpExpression(Context, node);
             }
 
+            public override void VisitCSharpStatement(CSharpStatementIRNode node)
+            {
+                Context.BasicWriter.WriteCSharpStatement(Context, node);
+            }
+
             public override void VisitDefault(RazorIRNode node)
             {
                 // This is a temporary bridge to the renderer, which allows us to move functionality piecemeal

src/Microsoft.AspNetCore.Razor.Evolution/CodeGeneration/DesignTimeBasicWriter.cs

@@ -2,6 +2,7 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Linq;
 using Microsoft.AspNetCore.Razor.Evolution.Intermediate;
 
 namespace Microsoft.AspNetCore.Razor.Evolution.CodeGeneration
@@ -71,7 +72,55 @@ namespace Microsoft.AspNetCore.Razor.Evolution.CodeGeneration
 
         public override void WriteCSharpStatement(CSharpRenderingContext context, CSharpStatementIRNode node)
         {
-            throw new NotImplementedException();
+            var isWhitespaceStatement = true;
+            for (var i = 0; i < node.Children.Count; i++)
+            {
+                var token = node.Children[i] as RazorIRToken;
+                if (token == null || !string.IsNullOrWhiteSpace(token.Content))
+                {
+                    isWhitespaceStatement = false;
+                    break;
+                }
+            }
+
+            IDisposable linePragmaScope = null;
+            if (node.Source != null)
+            {
+                if (!isWhitespaceStatement)
+                {
+                    linePragmaScope = context.Writer.BuildLinePragma(node.Source.Value);
+                }
+
+                context.Writer.WritePadding(0, node.Source.Value, context);
+            }
+            else if (isWhitespaceStatement)
+            {
+                // Don't write whitespace if there is no line mapping for it.
+                return;
+            }
+
+            for (var i = 0; i < node.Children.Count; i++)
+            {
+                if (node.Children[i] is RazorIRToken token && token.IsCSharp)
+                {
+                    context.AddLineMappingFor(token);
+                    context.Writer.Write(token.Content);
+                }
+                else
+                {
+                    // There may be something else inside the statement like an extension node.
+                    context.RenderNode(node.Children[i]);
+                }
+            }
+
+            if (linePragmaScope != null)
+            {
+                linePragmaScope.Dispose();
+            }
+            else
+            {
+                context.Writer.WriteLine();
+            }
         }
 
         public override void WriteHtmlAttribute(CSharpRenderingContext context, HtmlAttributeIRNode node)

src/Microsoft.AspNetCore.Razor.Evolution/CodeGeneration/DesignTimeCSharpRenderer.cs

@@ -78,13 +78,22 @@ namespace Microsoft.AspNetCore.Razor.Evolution.CodeGeneration
 
         public override void VisitCSharpStatement(CSharpStatementIRNode node)
         {
-            var isWhitespaceToken = node.Children.All(child =>
+            // We can't remove this yet, because it's still used recursively in a few places.
-                child is RazorIRToken token && string.IsNullOrWhiteSpace(token.Content));
+            var isWhitespaceStatement = true;
+            for (var i = 0; i < node.Children.Count; i++)
+            {
+                var token = node.Children[i] as RazorIRToken;
+                if (token == null || !string.IsNullOrWhiteSpace(token.Content))
+                {
+                    isWhitespaceStatement = false;
+                    break;
+                }
+            }
 
             IDisposable linePragmaScope = null;
             if (node.Source != null)
             {
-                if (!isWhitespaceToken)
+                if (!isWhitespaceStatement)
                 {
                     linePragmaScope = Context.Writer.BuildLinePragma(node.Source.Value);
                 }
@@ -92,7 +101,7 @@ namespace Microsoft.AspNetCore.Razor.Evolution.CodeGeneration
                 var padding = BuildOffsetPadding(0, node.Source.Value, Context);
                 Context.Writer.Write(padding);
             }
-            else if (isWhitespaceToken)
+            else if (isWhitespaceStatement)
             {
                 // Don't write whitespace if there is no line mapping for it.
                 return;
@@ -102,7 +111,7 @@ namespace Microsoft.AspNetCore.Razor.Evolution.CodeGeneration
             {
                 if (node.Children[i] is RazorIRToken token && token.IsCSharp)
                 {
-                    Context.AddLineMappingFor(node);
+                    Context.AddLineMappingFor(token);
                     Context.Writer.Write(token.Content);
                 }
                 else

src/Microsoft.AspNetCore.Razor.Evolution/CodeGeneration/RuntimeBasicWriter.cs

@@ -2,6 +2,7 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
+using System.Linq;
 using Microsoft.AspNetCore.Razor.Evolution.Intermediate;
 
 namespace Microsoft.AspNetCore.Razor.Evolution.CodeGeneration
@@ -51,7 +52,48 @@ namespace Microsoft.AspNetCore.Razor.Evolution.CodeGeneration
 
         public override void WriteCSharpStatement(CSharpRenderingContext context, CSharpStatementIRNode node)
         {
-            throw new NotImplementedException();
+            var isWhitespaceStatement = true;
+            for (var i = 0; i < node.Children.Count; i++)
+            {
+                var token = node.Children[i] as RazorIRToken;
+                if (token == null || !string.IsNullOrWhiteSpace(token.Content))
+                {
+                    isWhitespaceStatement = false;
+                    break;
+                }
+            }
+
+            if (isWhitespaceStatement)
+            {
+                return;
+            }
+
+            IDisposable linePragmaScope = null;
+            if (node.Source != null)
+            {
+                linePragmaScope = context.Writer.BuildLinePragma(node.Source.Value);
+                context.Writer.WritePadding(0, node.Source.Value, context);
+            }
+
+            for (var i = 0; i < node.Children.Count; i++)
+            {
+                if (node.Children[i] is RazorIRToken token && token.IsCSharp)
+                {
+                    context.Writer.Write(token.Content);
+                }
+                else
+                {
+                    // There may be something else inside the statement like an extension node.
+                    context.RenderNode(node.Children[i]);
+                }
+            }
+
+            if (linePragmaScope == null)
+            {
+                context.Writer.WriteLine();
+            }
+
+            linePragmaScope?.Dispose();
         }
 
         public override void WriteHtmlAttribute(CSharpRenderingContext context, HtmlAttributeIRNode node)

src/Microsoft.AspNetCore.Razor.Evolution/CodeGeneration/RuntimeCSharpRenderer.cs

@@ -210,10 +210,19 @@ namespace Microsoft.AspNetCore.Razor.Evolution.CodeGeneration
 
         public override void VisitCSharpStatement(CSharpStatementIRNode node)
         {
-            var isWhitespaceToken = node.Children.All(child =>
+            // We can't remove this yet, because it's still used recursively in a few places.
-                child is RazorIRToken token && string.IsNullOrWhiteSpace(token.Content));
+            var isWhitespaceStatement = true;
+            for (var i = 0; i < node.Children.Count; i++)
+            {
+                var token = node.Children[i] as RazorIRToken;
+                if (token == null || !string.IsNullOrWhiteSpace(token.Content))
+                {
+                    isWhitespaceStatement = false;
+                    break;
+                }
+            }
 
-            if (isWhitespaceToken)
+            if (isWhitespaceStatement)
             {
                 return;
             }

test/Microsoft.AspNetCore.Razor.Evolution.Test/CodeGeneration/DesignTimeBasicWriterTest.cs

@@ -161,6 +161,177 @@ __o = i++;
 @"#line 1 ""test.cshtml""
   __o = i++;
 
+#line default
+#line hidden
+",
+                csharp,
+                ignoreLineEndingDifferences: true);
+        }
+
+        [Fact]
+        public void WriteCSharpStatement_WhitespaceContent_DoesNothing()
+        {
+            // Arrange
+            var writer = new DesignTimeBasicWriter();
+
+            var context = new CSharpRenderingContext()
+            {
+                Writer = new Legacy.CSharpCodeWriter(),
+            };
+
+            var node = new CSharpStatementIRNode();
+            RazorIRBuilder.Create(node)
+                .Add(new RazorIRToken()
+                {
+                    Kind = RazorIRToken.TokenKind.CSharp,
+                    Content = "  \t"
+                });
+
+            // Act
+            writer.WriteCSharpStatement(context, node);
+
+            // Assert
+            var csharp = context.Writer.Builder.ToString();
+            Assert.Empty(csharp);
+        }
+
+        [Fact]
+        public void WriteCSharpStatement_WhitespaceContentWithSource_WritesContent()
+        {
+            // Arrange
+            var writer = new DesignTimeBasicWriter();
+
+            var context = new CSharpRenderingContext()
+            {
+                Writer = new Legacy.CSharpCodeWriter(),
+                Options = RazorParserOptions.CreateDefaultOptions(),
+            };
+
+            var node = new CSharpStatementIRNode()
+            {
+                Source = new SourceSpan("test.cshtml", 0, 0, 0, 3),
+            };
+            RazorIRBuilder.Create(node)
+                .Add(new RazorIRToken()
+                {
+                    Kind = RazorIRToken.TokenKind.CSharp,
+                    Content = "    "
+                });
+
+            // Act
+            writer.WriteCSharpStatement(context, node);
+
+            // Assert
+            var csharp = context.Writer.Builder.ToString();
+            Assert.Equal(
+@"    
+",
+                csharp,
+                ignoreLineEndingDifferences: true);
+        }
+
+        [Fact]
+        public void WriteCSharpStatement_SkipsLinePragma_WithoutSource()
+        {
+            // Arrange
+            var writer = new DesignTimeBasicWriter();
+
+            var context = new CSharpRenderingContext()
+            {
+                Writer = new Legacy.CSharpCodeWriter(),
+            };
+
+            var node = new CSharpStatementIRNode();
+            RazorIRBuilder.Create(node)
+                .Add(new RazorIRToken()
+                {
+                    Kind = RazorIRToken.TokenKind.CSharp,
+                    Content = "if (true) { }"
+                });
+
+            // Act
+            writer.WriteCSharpStatement(context, node);
+
+            // Assert
+            var csharp = context.Writer.Builder.ToString();
+            Assert.Equal(
+@"if (true) { }
+",
+                csharp,
+                ignoreLineEndingDifferences: true);
+        }
+
+        [Fact]
+        public void WriteCSharpStatement_WritesLinePragma_WithSource()
+        {
+            // Arrange
+            var writer = new DesignTimeBasicWriter();
+
+            var context = new CSharpRenderingContext()
+            {
+                Writer = new Legacy.CSharpCodeWriter(),
+                Options = RazorParserOptions.CreateDefaultOptions(),
+            };
+
+            var node = new CSharpStatementIRNode()
+            {
+                Source = new SourceSpan("test.cshtml", 0, 0, 0, 13),
+            };
+            RazorIRBuilder.Create(node)
+                .Add(new RazorIRToken()
+                {
+                    Kind = RazorIRToken.TokenKind.CSharp,
+                    Content = "if (true) { }",
+                });
+
+            // Act
+            writer.WriteCSharpStatement(context, node);
+
+            // Assert
+            var csharp = context.Writer.Builder.ToString();
+            Assert.Equal(
+@"#line 1 ""test.cshtml""
+if (true) { }
+
+#line default
+#line hidden
+",
+                csharp,
+                ignoreLineEndingDifferences: true);
+        }
+
+        [Fact]
+        public void WriteCSharpStatement_WritesPadding_WithSource()
+        {
+            // Arrange
+            var writer = new DesignTimeBasicWriter();
+
+            var context = new CSharpRenderingContext()
+            {
+                Writer = new Legacy.CSharpCodeWriter(),
+                Options = RazorParserOptions.CreateDefaultOptions(),
+            };
+
+            var node = new CSharpStatementIRNode()
+            {
+                Source = new SourceSpan("test.cshtml", 0, 0, 0, 17),
+            };
+            RazorIRBuilder.Create(node)
+                .Add(new RazorIRToken()
+                {
+                    Kind = RazorIRToken.TokenKind.CSharp,
+                    Content = "    if (true) { }",
+                });
+
+            // Act
+            writer.WriteCSharpStatement(context, node);
+
+            // Assert
+            var csharp = context.Writer.Builder.ToString();
+            Assert.Equal(
+@"#line 1 ""test.cshtml""
+    if (true) { }
+
 #line default
 #line hidden
 ",

test/Microsoft.AspNetCore.Razor.Evolution.Test/CodeGeneration/RuntimeBasicWriterTest.cs

@@ -173,6 +173,142 @@ Test(i++);
 @"#line 1 ""test.cshtml""
    Test(i++);
 
+#line default
+#line hidden
+",
+                csharp,
+                ignoreLineEndingDifferences: true);
+        }
+
+        [Fact]
+        public void WriteCSharpStatement_WhitespaceContent_DoesNothing()
+        {
+            // Arrange
+            var writer = new RuntimeBasicWriter();
+
+            var context = new CSharpRenderingContext()
+            {
+                Writer = new Legacy.CSharpCodeWriter(),
+            };
+
+            var node = new CSharpStatementIRNode();
+            RazorIRBuilder.Create(node)
+                .Add(new RazorIRToken()
+                {
+                    Kind = RazorIRToken.TokenKind.CSharp,
+                    Content = "  \t"
+                });
+
+            // Act
+            writer.WriteCSharpStatement(context, node);
+
+            // Assert
+            var csharp = context.Writer.Builder.ToString();
+            Assert.Empty(csharp);
+        }
+
+        [Fact]
+        public void WriteCSharpStatement_SkipsLinePragma_WithoutSource()
+        {
+            // Arrange
+            var writer = new RuntimeBasicWriter();
+
+            var context = new CSharpRenderingContext()
+            {
+                Writer = new Legacy.CSharpCodeWriter(),
+            };
+
+            var node = new CSharpStatementIRNode();
+            RazorIRBuilder.Create(node)
+                .Add(new RazorIRToken()
+                {
+                    Kind = RazorIRToken.TokenKind.CSharp,
+                    Content = "if (true) { }"
+                });
+
+            // Act
+            writer.WriteCSharpStatement(context, node);
+
+            // Assert
+            var csharp = context.Writer.Builder.ToString();
+            Assert.Equal(
+@"if (true) { }
+",
+                csharp,
+                ignoreLineEndingDifferences: true);
+        }
+
+        [Fact]
+        public void WriteCSharpStatement_WritesLinePragma_WithSource()
+        {
+            // Arrange
+            var writer = new RuntimeBasicWriter();
+
+            var context = new CSharpRenderingContext()
+            {
+                Writer = new Legacy.CSharpCodeWriter(),
+                Options = RazorParserOptions.CreateDefaultOptions(),
+            };
+
+            var node = new CSharpStatementIRNode()
+            {
+                Source = new SourceSpan("test.cshtml", 0, 0, 0, 13),
+            };
+            RazorIRBuilder.Create(node)
+                .Add(new RazorIRToken()
+                {
+                    Kind = RazorIRToken.TokenKind.CSharp,
+                    Content = "if (true) { }",
+                });
+
+            // Act
+            writer.WriteCSharpStatement(context, node);
+
+            // Assert
+            var csharp = context.Writer.Builder.ToString();
+            Assert.Equal(
+@"#line 1 ""test.cshtml""
+if (true) { }
+
+#line default
+#line hidden
+",
+                csharp,
+                ignoreLineEndingDifferences: true);
+        }
+
+        [Fact]
+        public void WriteCSharpStatement_WritesPadding_WithSource()
+        {
+            // Arrange
+            var writer = new RuntimeBasicWriter();
+
+            var context = new CSharpRenderingContext()
+            {
+                Writer = new Legacy.CSharpCodeWriter(),
+                Options = RazorParserOptions.CreateDefaultOptions(),
+            };
+
+            var node = new CSharpStatementIRNode()
+            {
+                Source = new SourceSpan("test.cshtml", 0, 0, 0, 17),
+            };
+            RazorIRBuilder.Create(node)
+                .Add(new RazorIRToken()
+                {
+                    Kind = RazorIRToken.TokenKind.CSharp,
+                    Content = "    if (true) { }",
+                });
+
+            // Act
+            writer.WriteCSharpStatement(context, node);
+
+            // Assert
+            var csharp = context.Writer.Builder.ToString();
+            Assert.Equal(
+@"#line 1 ""test.cshtml""
+    if (true) { }
+
 #line default
 #line hidden
 ",