Add elastic trivia to Inline Declaration if necessary (#47916)

src/Analyzers/CSharp/CodeFixes/InlineDeclaration/CSharpInlineDeclarationCodeFixProvider.cs

@@ -288,7 +288,6 @@ private static DeclarationExpressionSyntax GetDeclarationExpression(
             SourceText sourceText, IdentifierNameSyntax identifier,
             TypeSyntax newType, VariableDeclaratorSyntax declaratorOpt)
         {
-            newType = newType.WithoutTrivia().WithAdditionalAnnotations(Formatter.Annotation);
             var designation = SyntaxFactory.SingleVariableDesignation(identifier.Identifier);
 
             if (declaratorOpt != null)
@@ -310,6 +309,15 @@ private static DeclarationExpressionSyntax GetDeclarationExpression(
                 }
             }
 
+            newType = newType.WithoutTrivia().WithAdditionalAnnotations(Formatter.Annotation);
+            // We need trivia between the type declaration and designation or this will generate
+            // "out inti", but we might have trivia in the form of comments etc from the original
+            // designation and in those cases adding elastic trivia will break formatting.
+            if (!designation.HasLeadingTrivia)
+            {
+                newType = newType.WithAppendedTrailingTrivia(SyntaxFactory.ElasticSpace);
+            }
+
             return SyntaxFactory.DeclarationExpression(newType, designation);
         }
 

src/Analyzers/CSharp/Tests/InlineDeclaration/CSharpInlineDeclarationTests.cs

@@ -2292,5 +2292,26 @@ await TestMissingAsync(@"
 {
 }", new TestParameters(TestOptions.Regular));
         }
+
+        [WorkItem(47041, "https://github.com/dotnet/roslyn/issues/47041")]
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsInlineDeclaration)]
+        public async Task CollectionInitializer()
+        {
+            await TestInRegularAndScript1Async(
+@"class C
+{
+    private List<Func<string, bool>> _funcs2 = new List<Func<string, bool>>()
+    {
+        s => { int [|i|] = 0; return int.TryParse(s, out i); }
+    };
+}",
+@"class C
+{
+    private List<Func<string, bool>> _funcs2 = new List<Func<string, bool>>()
+    {
+        s => { return int.TryParse(s, out int i); }
+    };
+}");
+        }
     }
 }