Fix code review comments

Author: Lakshmi Priya Sekar

src/Microsoft.DotNet.CodeFormatting/Rules/HasNoCustomCopyrightHeaderFormattingRule.cs

@@ -21,16 +21,21 @@ internal sealed class HasNoCustomCopyrightHeaderFormattingRule : IFormattingRule
         private static string StartMarker { get; set;}
         private static string EndMarker { get; set; }
 
+        private const string FileNotFoundError = "The specified CopyrightHeader.md file was not found.";
+
+        private const string FileSyntaxError = "There should be exactly 3 lines in CopyrightHeader.md.";
+
         public async Task<Document> ProcessAsync(Document document, CancellationToken cancellationToken)
         {
             var syntaxNode = await document.GetSyntaxRootAsync(cancellationToken) as CSharpSyntaxNode;
             if (syntaxNode == null)
                 return document;
 
-            var triviaList = syntaxNode.GetLeadingTrivia();
-
             // SetHeaders
-            SetHeaders();
+            if (!SetHeaders())
+                return document;
+
+            var triviaList = syntaxNode.GetLeadingTrivia();
 
             SyntaxTrivia start;
             SyntaxTrivia end;
@@ -113,25 +118,30 @@ private static bool IsEndOfXmlHeader(SyntaxTrivia trivia, out SyntaxTrivia end)
                          .FirstOrDefault();
         }
 
-        private static void SetHeaders()
+        private static bool SetHeaders()
         {
             var filePath = Path.Combine(
                 Path.GetDirectoryName(Uri.UnescapeDataString(new UriBuilder(Assembly.GetExecutingAssembly().CodeBase).Path)),
                 "CopyrightHeader.md");
 
             if (!File.Exists(filePath))
             {
-                RulerMarker = "";
-                StartMarker = "";
-                EndMarker = "";
+                FileNotFoundError.WriteConsoleError(1, "CopyrightHeader.md");
+                return false;
             }
-            else
+
+            var lines = File.ReadAllLines(filePath).Where(l => !l.StartsWith("##") && !l.Equals("")).ToArray();
+            if (lines.Count() != 3)
             {
-                var lines = File.ReadAllLines(filePath).Where(l => !l.StartsWith("##") && !l.Equals("")).ToArray();
-                RulerMarker = lines[0];
-                StartMarker = lines[1];
-                EndMarker = lines[2];
+                FileSyntaxError.WriteConsoleError(1, "CopyrightHeader.md");
+                return false;
             }
-        }
+
+            RulerMarker = lines[0];
+            StartMarker = lines[1];
+            EndMarker = lines[2];
+
+            return true;
+        }       
     }
 }

src/Microsoft.DotNet.CodeFormatting/Rules/HasNoIllegalHeadersFormattingRule.cs

@@ -60,18 +60,15 @@ private static SyntaxTriviaList RemoveTrivia(SyntaxTriviaList leadingTrivia, Syn
         {
             SyntaxTriviaList newTrivia = leadingTrivia;
             var index = leadingTrivia.IndexOf(trivia);
-            if (leadingTrivia.ElementAt(index + 1).CSharpKind() == SyntaxKind.EndOfLineTrivia)
+
+            // Remove trivia
+            newTrivia = newTrivia.RemoveAt(index);
+
+            if (index < newTrivia.Count && newTrivia.ElementAt(index).CSharpKind() == SyntaxKind.EndOfLineTrivia)
             {
-                // Remove trivia
-                newTrivia = newTrivia.RemoveAt(index);
                 // Remove end of line after trivia
                 newTrivia = newTrivia.RemoveAt(index);
             }
-            else
-            {
-                // Remove trivia
-                newTrivia = newTrivia.RemoveAt(index);
-            }
 
             return newTrivia;
         }

src/Microsoft.DotNet.CodeFormatting/Rules/HasNoNewLineBeforeEndBraceFormattingRule.cs

@@ -74,16 +74,17 @@ private static IEnumerable<SyntaxTrivia> RemoveNewLinesFromBotton(IEnumerable<Sy
                 }
             }
 
+            var newTrivia = trivia.Take(elementsToRemoveAtEnd + 1);
+
             if (addWhitespace)
             {
-                var newTrivia = trivia.Take(elementsToRemoveAtEnd + 1);
                 if (newTrivia.Last().IsDirective)
                     return newTrivia.AddWhiteSpaceTrivia();
 
                 return newTrivia.AddNewLine().AddWhiteSpaceTrivia();
             }
 
-            return trivia.Take(elementsToRemoveAtEnd + 1);
+            return newTrivia;
         }
     }
 }