Add With* convenience methods to SourceSpan

src/Compiler/Microsoft.CodeAnalysis.Razor.Compiler/src/Language/DefaultTagHelperResolutionPhase.ComponentTagHelperResolver.cs

@@ -195,15 +195,18 @@ private void ConvertToUnresolvedDirectiveAttribute(
             var directiveNameSpan = nameSpan;
             if (directiveNameSpan is SourceSpan ns && attributeName.StartsWith('@'))
             {
-                directiveNameSpan = new SourceSpan(ns.FilePath, ns.AbsoluteIndex + 1, ns.LineIndex, ns.CharacterIndex + 1, ns.Length - 1, ns.LineCount, ns.EndCharacterIndex);
+                directiveNameSpan = ns.WithAbsoluteIndex(ns.AbsoluteIndex + 1)
+                    .WithCharacterIndex(ns.CharacterIndex + 1)
+                    .WithLength(ns.Length - 1);
             }
 
             // Strip parameter suffix from OriginalAttributeSpan for parameter matches
             var parameterOriginalSpan = directiveNameSpan;
             if (match.IsParameterMatch && directiveAttributeName.HasParameter && parameterOriginalSpan is SourceSpan ps)
             {
                 var nameWithoutParamLen = directiveAttributeName.TextWithoutParameter.Length;
-                parameterOriginalSpan = new SourceSpan(ps.FilePath, ps.AbsoluteIndex, ps.LineIndex, ps.CharacterIndex, nameWithoutParamLen, ps.LineCount, ps.CharacterIndex + nameWithoutParamLen);
+                parameterOriginalSpan = ps.WithLength(nameWithoutParamLen)
+                    .WithEndCharacterIndex(ps.CharacterIndex + nameWithoutParamLen);
             }
 
             IntermediateNode directiveNode = match.IsParameterMatch && directiveAttributeName.HasParameter
@@ -869,14 +872,9 @@ private static void ConvertComponentAttributeToTagHelper(
                         var directiveNameSpan = attributeNameSpan;
                         if (directiveNameSpan is SourceSpan nameSpan && attributeName.StartsWith('@'))
                         {
-                            directiveNameSpan = new SourceSpan(
-                                nameSpan.FilePath,
-                                nameSpan.AbsoluteIndex + 1,
-                                nameSpan.LineIndex,
-                                nameSpan.CharacterIndex + 1,
-                                nameSpan.Length - 1,
-                                nameSpan.LineCount,
-                                nameSpan.EndCharacterIndex);
+                            directiveNameSpan = nameSpan.WithAbsoluteIndex(nameSpan.AbsoluteIndex + 1)
+                                .WithCharacterIndex(nameSpan.CharacterIndex + 1)
+                                .WithLength(nameSpan.Length - 1);
                         }
 
                         IntermediateNode directiveNode = match.IsParameterMatch && directiveAttributeName.HasParameter
@@ -983,7 +981,7 @@ private static void CopyAsTagHelperAttributeValues(HtmlAttributeIntermediateNode
                     var totalLength = source.Children[^1] is HtmlAttributeValueIntermediateNode lastValue && lastValue.Source is { } ls
                         ? (ls.AbsoluteIndex + ls.Length) - fs.AbsoluteIndex
                         : mergedText.Length;
-                    spanSource = new SourceSpan(fs.FilePath, fs.AbsoluteIndex, fs.LineIndex, fs.CharacterIndex, totalLength, fs.LineCount, fs.EndCharacterIndex);
+                    spanSource = fs.WithLength(totalLength);
                 }
 
                 mergedContent.Source = spanSource;
@@ -1044,14 +1042,11 @@ private static void CopyAsTagHelperAttributeValues(HtmlAttributeIntermediateNode
 
             var nameCharIndex = attrSource.CharacterIndex + nameIndex;
 
-            return new SourceSpan(
-                attrSource.FilePath,
-                attrSource.AbsoluteIndex + nameIndex,
-                attrSource.LineIndex,
-                nameCharIndex,
-                nameLength,
-                0,
-                nameCharIndex + nameLength);
+            return attrSource.WithAbsoluteIndex(attrSource.AbsoluteIndex + nameIndex)
+                .WithCharacterIndex(nameCharIndex)
+                .WithLength(nameLength)
+                .WithLineCount(0)
+                .WithEndCharacterIndex(nameCharIndex + nameLength);
         }
 
         private static SourceSpan? ComputeAttributeValueSpan(HtmlAttributeIntermediateNode htmlAttr)
@@ -1072,16 +1067,11 @@ private static void CopyAsTagHelperAttributeValues(HtmlAttributeIntermediateNode
                     var endIndex = lastSource.AbsoluteIndex + lastSource.Length;
                     var length = endIndex - childSource.AbsoluteIndex;
                     var endCharIndex = lastSource.CharacterIndex + lastSource.Length;
-                    return new SourceSpan(
-                        childSource.FilePath,
-                        childSource.AbsoluteIndex,
-                        childSource.LineIndex,
-                        childSource.CharacterIndex,
-                        length,
+                    return childSource.WithLength(length)
                         // Note: does not incorporate lastSource.LineCount; attribute values
                         // spanning multiple lines are uncommon and the old pipeline had the same limitation.
-                        lastSource.LineIndex - childSource.LineIndex,
-                        endCharIndex);
+                        .WithLineCount(lastSource.LineIndex - childSource.LineIndex)
+                        .WithEndCharacterIndex(endCharIndex);
                 }
 
                 return childSource;
@@ -1105,14 +1095,11 @@ private static void CopyAsTagHelperAttributeValues(HtmlAttributeIntermediateNode
 
             var valueCharIndex = attrSource.CharacterIndex + valueStart;
 
-            return new SourceSpan(
-                attrSource.FilePath,
-                attrSource.AbsoluteIndex + valueStart,
-                attrSource.LineIndex,
-                valueCharIndex,
-                valueLength,
-                0,
-                valueCharIndex + valueLength);
+            return attrSource.WithAbsoluteIndex(attrSource.AbsoluteIndex + valueStart)
+                .WithCharacterIndex(valueCharIndex)
+                .WithLength(valueLength)
+                .WithLineCount(0)
+                .WithEndCharacterIndex(valueCharIndex + valueLength);
         }
 
         /// <summary>

src/Compiler/Microsoft.CodeAnalysis.Razor.Compiler/src/Language/DefaultTagHelperResolutionPhase.cs

@@ -806,8 +806,10 @@ private static SourceSpan MergeSpans(SourceSpan a, SourceSpan b)
         var first = a.AbsoluteIndex <= b.AbsoluteIndex ? a : b;
         var last = a.AbsoluteIndex + a.Length >= b.AbsoluteIndex + b.Length ? a : b;
         var lineCount = (last.LineIndex + last.LineCount) - first.LineIndex;
-        return new SourceSpan(first.FilePath, start, first.LineIndex, first.CharacterIndex,
-            end - start, lineCount, last.EndCharacterIndex);
+        return first.WithAbsoluteIndex(start)
+            .WithLength(end - start)
+            .WithLineCount(lineCount)
+            .WithEndCharacterIndex(last.EndCharacterIndex);
     }
 
     /// <summary>
@@ -918,9 +920,10 @@ private static void EmitEscapedAtCSharpExpression(
         EmitExplicitExpressionTokens(expr, expressionSource.AbsoluteIndex, expressionSource.Length, sourceDocument);
 
         var exprLoc = sourceDocument.Text.Lines.GetLinePosition(expressionSource.AbsoluteIndex);
-        expr.Source = new SourceSpan(
-            expressionSource.FilePath, expressionSource.AbsoluteIndex,
-            exprLoc.Line, exprLoc.Character, expressionSource.Length, 0, exprLoc.Character + expressionSource.Length);
+        expr.Source = expressionSource.WithLineIndex(exprLoc.Line)
+            .WithCharacterIndex(exprLoc.Character)
+            .WithLineCount(0)
+            .WithEndCharacterIndex(exprLoc.Character + expressionSource.Length);
         target.Children.Add(expr);
     }
 
@@ -1002,14 +1005,9 @@ private static bool AreAllChildrenOfType<T>(IntermediateNodeCollection children)
             return null;
         }
 
-        return new SourceSpan(
-            s.FilePath,
-            s.AbsoluteIndex - prefixLength,
-            s.LineIndex,
-            s.CharacterIndex - prefixLength,
-            s.Length + prefixLength,
-            s.LineCount,
-            s.EndCharacterIndex);
+        return s.WithAbsoluteIndex(s.AbsoluteIndex - prefixLength)
+            .WithCharacterIndex(s.CharacterIndex - prefixLength)
+            .WithLength(s.Length + prefixLength);
     }
 
     /// <summary>
@@ -1102,9 +1100,11 @@ private static void TryAddMalformedEndTagDiagnostic(
         var diagSource = elementNode.Source;
         if (elementNode.EndTagSpan is SourceSpan ets)
         {
-            diagSource = new SourceSpan(
-                ets.FilePath, ets.AbsoluteIndex + 2, ets.LineIndex, ets.CharacterIndex + 2,
-                tagName.Length, 0, ets.CharacterIndex + 2 + tagName.Length);
+            diagSource = ets.WithAbsoluteIndex(ets.AbsoluteIndex + 2)
+                .WithCharacterIndex(ets.CharacterIndex + 2)
+                .WithLength(tagName.Length)
+                .WithLineCount(0)
+                .WithEndCharacterIndex(ets.CharacterIndex + 2 + tagName.Length);
         }
 
         if (diagSource is SourceSpan ds)

src/Compiler/Microsoft.CodeAnalysis.Razor.Compiler/src/Language/SourceSpan.cs

@@ -9,7 +9,7 @@
 
 namespace Microsoft.AspNetCore.Razor.Language;
 
-public struct SourceSpan : IEquatable<SourceSpan>
+public readonly struct SourceSpan : IEquatable<SourceSpan>
 {
     public static readonly SourceSpan Undefined = new SourceSpan(SourceLocation.Undefined, 0);
 
@@ -126,4 +126,12 @@ public readonly int CompareByStartThenLength(SourceSpan other)
 
         return Length.CompareTo(other.Length);
     }
+
+    public readonly SourceSpan WithFilePath(string filePath) => new(filePath, AbsoluteIndex, LineIndex, CharacterIndex, Length, LineCount, EndCharacterIndex);
+    public readonly SourceSpan WithAbsoluteIndex(int absoluteIndex) => new(FilePath, absoluteIndex, LineIndex, CharacterIndex, Length, LineCount, EndCharacterIndex);
+    public readonly SourceSpan WithLineIndex(int lineIndex) => new(FilePath, AbsoluteIndex, lineIndex, CharacterIndex, Length, LineCount, EndCharacterIndex);
+    public readonly SourceSpan WithCharacterIndex(int characterIndex) => new(FilePath, AbsoluteIndex, LineIndex, characterIndex, Length, LineCount, EndCharacterIndex);
+    public readonly SourceSpan WithLength(int length) => new(FilePath, AbsoluteIndex, LineIndex, CharacterIndex, length, LineCount, EndCharacterIndex);
+    public readonly SourceSpan WithLineCount(int lineCount) => new(FilePath, AbsoluteIndex, LineIndex, CharacterIndex, Length, lineCount, EndCharacterIndex);
+    public readonly SourceSpan WithEndCharacterIndex(int endCharacterIndex) => new(FilePath, AbsoluteIndex, LineIndex, CharacterIndex, Length, LineCount, endCharacterIndex);
 }