Remove Trivia from expression in newFieldDeclaration

src/EditorFeatures/CSharpTest/CodeActions/IntroduceVariable/IntroduceVariableTests.cs

@@ -175,6 +175,26 @@ public async Task TestFieldFix2()
             await TestInRegularAndScriptAsync(code, expected, index: 1);
         }
 
+        [WorkItem(21747, "https://github.com/dotnet/roslyn/issues/21747")]
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsIntroduceVariable)]
+        public async Task TestTriviaFieldFix1()
+        {
+            var code =
+@"class C
+{
+    int i = (/* CommentLeading */ [|1 + 1|] /* CommentTrailing */) + (1 + 1);
+}";
+
+            var expected =
+@"class C
+{
+    private const int {|Rename:V|} = 1 + 1;
+    int i = /* CommentLeading */ V /* CommentTrailing */ + V;
+}";
+
+            await TestInRegularAndScriptAsync(code, expected, index: 1);
+        }
+
         [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsIntroduceVariable)]
         public async Task TestConstFieldFix1()
         {

src/Features/CSharp/Portable/IntroduceVariable/CSharpIntroduceVariableService_IntroduceField.cs

@@ -43,7 +43,7 @@ internal partial class CSharpIntroduceVariableService
                         SyntaxFactory.VariableDeclarator(
                             newNameToken.WithAdditionalAnnotations(RenameAnnotation.Create()),
                             null,
-                            SyntaxFactory.EqualsValueClause(expression))))).WithAdditionalAnnotations(Formatter.Annotation);
+                            SyntaxFactory.EqualsValueClause(expression.WithoutTrailingTrivia().WithoutLeadingTrivia()))))).WithAdditionalAnnotations(Formatter.Annotation);
 
             if (oldTypeDeclaration != null)
             {