Simplified SyntaxTree.IsEmpty()

Author: sharwell

StyleCop.Analyzers/StyleCop.Analyzers/Helpers/SyntaxTreeHelpers.cs

@@ -68,12 +68,9 @@ public static bool IsWhitespaceOnly(this SyntaxTree tree, CancellationToken canc
                 && TriviaHelper.IndexOfFirstNonWhitespaceTrivia(firstToken.LeadingTrivia) == -1;
         }
 
-        public static bool IsEmpty(this SyntaxTree tree, CancellationToken cancellationToken)
+        public static bool IsEmpty(this SyntaxTree tree)
         {
-            var root = tree.GetRoot(cancellationToken);
-            var firstToken = root.GetFirstToken(includeZeroWidth: true);
-
-            return firstToken.IsKind(SyntaxKind.EndOfFileToken) && firstToken.FullSpan.IsEmpty;
+            return tree.Length == 0;
         }
     }
 }

StyleCop.Analyzers/StyleCop.Analyzers/LayoutRules/SA1518UseLineEndingsCorrectlyAtEndOfFile.cs

@@ -72,6 +72,12 @@ public override void Initialize(AnalysisContext context)
 
         private static void HandleSyntaxTree(SyntaxTreeAnalysisContext context, StyleCopSettings settings)
         {
+            if (context.Tree.IsEmpty())
+            {
+                // Empty files never contain line endings.
+                return;
+            }
+
             var endOfFileToken = context.Tree.GetRoot().GetLastToken(includeZeroWidth: true);
             TextSpan reportedSpan = new TextSpan(endOfFileToken.SpanStart, 0);
 
@@ -185,12 +191,6 @@ private static void HandleSyntaxTree(SyntaxTreeAnalysisContext context, StyleCop
                 break;
             }
 
-            if (context.Tree.IsEmpty(context.CancellationToken))
-            {
-                // Empty files never contain line endings.
-                return;
-            }
-
             context.ReportDiagnostic(Diagnostic.Create(descriptorToReport, Location.Create(context.Tree, reportedSpan)));
         }
     }