Merge pull request #11685 from CyrusNajmabadi/preserveAttributeOnSingleLine

Keep attribute on the same line as a member if they started on a single line

Fixes #11572 

src/Workspaces/CSharp/Portable/Formatting/Rules/SpacingFormattingRule.cs

@@ -182,6 +182,17 @@ public override AdjustSpacesOperation GetAdjustSpacesOperation(SyntaxToken previ
                 return AdjustSpacesOperationZeroOrOne(optionSet, CSharpFormattingOptions.SpaceWithinSquareBrackets);
             }
 
+            // attribute case ] *
+            // Place a space between the attribute and the next member if they're on the same line.
+            if (previousKind == SyntaxKind.CloseBracketToken && previousToken.Parent.IsKind(SyntaxKind.AttributeList))
+            {
+                var attributeOwner = previousToken.Parent?.Parent;
+                if (attributeOwner is MemberDeclarationSyntax)
+                {
+                    return CreateAdjustSpacesOperation(1, AdjustSpacesOption.ForceSpacesIfOnSingleLine);
+                }
+            }
+
             // For spacing delimiters - after colon
             if (previousToken.IsColonInTypeBaseList())
             {

src/Workspaces/CSharp/Portable/Formatting/Rules/SuppressFormattingRule.cs

@@ -2,6 +2,7 @@
 
 using System.Collections.Generic;
 using System.Composition;
+using Microsoft.CodeAnalysis.CSharp.Extensions;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Formatting.Rules;
 using Microsoft.CodeAnalysis.Options;
@@ -64,8 +65,24 @@ private void AddSpecificNodesSuppressOperations(List<SuppressOperation> list, Sy
             var memberDeclNode = node as MemberDeclarationSyntax;
             if (memberDeclNode != null)
             {
+                // Attempt to keep the part of a member that follows hte attributes on a single
+                // line if that's how it's currently written.
                 var tokens = memberDeclNode.GetFirstAndLastMemberDeclarationTokensAfterAttributes();
                 AddSuppressWrappingIfOnSingleLineOperation(list, tokens.Item1, tokens.Item2);
+                
+                var attributes = memberDeclNode.GetAttributes();
+                if (attributes.Count > 0)
+                {
+                    // Also, If the member is on single line with its attributes on it, then keep 
+                    // it on a single line.  This is for code like the following:
+                    //
+                    //      [Import] public int Field1;
+                    //      [Import] public int Field2;
+                    AddSuppressWrappingIfOnSingleLineOperation(list,
+                        node.GetFirstToken(includeZeroWidth: true),
+                        node.GetLastToken(includeZeroWidth: true));
+                }
+
                 var propertyDeclNode = node as PropertyDeclarationSyntax;
                 if (propertyDeclNode?.Initializer != null && propertyDeclNode?.AccessorList != null)
                 {

src/Workspaces/CSharpTest/Formatting/FormattingTests.cs

@@ -3317,8 +3317,7 @@ public async Task Attributes1()
         {
             await AssertFormatAsync(@"class Program
 {
-    [Flags]
-    public void Method() { }
+    [Flags] public void Method() { }
 }", @"class Program
 {
         [   Flags       ]       public       void       Method      (       )           {           }
@@ -7401,6 +7400,22 @@ public void M()
             await AssertFormatAsync(code, code);
         }
 
+        [Fact, Trait(Traits.Feature, Traits.Features.Formatting)]
+        [WorkItem(11572, "https://github.com/dotnet/roslyn/issues/11572")]
+        public async Task FormatAttributeOnSameLineAsField()
+        {
+            await AssertFormatAsync(
+@"
+class C
+{
+    [Attr] int i;
+}",
+@"
+class C {
+    [Attr]   int   i;
+}");
+        }
+
         [Fact, Trait(Traits.Feature, Traits.Features.Formatting)]
         [WorkItem(6628, "https://github.com/dotnet/roslyn/issues/6628")]
         public async Task FormatOnElseBlockBracesOnSameLineRemainsInSameLine_2()