Allowing new lines in initializers (#1113)

closes #1110

Src/CSharpier.Tests/FormattingTests/TestFiles/cs/AnonymousObjectCreationExpressions_NewLines.expected.test

@@ -0,0 +1,9 @@
+var someObject = new
+{
+    NoLineAboveHere = 1,
+
+    ThisLineIsOkay = 2,
+
+    // comment
+    AndThisLine = 3,
+};

Src/CSharpier.Tests/FormattingTests/TestFiles/cs/AnonymousObjectCreationExpressions_NewLines.test

@@ -0,0 +1,10 @@
+var someObject = new
+{
+
+    NoLineAboveHere = 1,
+
+    ThisLineIsOkay = 2,
+
+    // comment
+    AndThisLine = 3,
+};

Src/CSharpier.Tests/FormattingTests/TestFiles/cs/InitializerExpressions_NewLines.expected.test

@@ -0,0 +1,9 @@
+var someObject = new SomeObject
+{
+    NoLineAboveHere = 1,
+
+    ThisLineIsOkay = 2,
+
+    // comment
+    AndThisLine = 3,
+};

Src/CSharpier.Tests/FormattingTests/TestFiles/cs/InitializerExpressions_NewLines.test

@@ -0,0 +1,10 @@
+var someObject = new SomeObject
+{
+
+    NoLineAboveHere = 1,
+
+    ThisLineIsOkay = 2,
+
+    // comment
+    AndThisLine = 3,
+};

Src/CSharpier/SyntaxPrinter/SyntaxNodePrinters/AnonymousObjectMemberDeclarator.cs

@@ -5,6 +5,14 @@ internal static class AnonymousObjectMemberDeclarator
     public static Doc Print(AnonymousObjectMemberDeclaratorSyntax node, FormattingContext context)
     {
         var docs = new List<Doc>();
+        if (
+            node.Parent is AnonymousObjectCreationExpressionSyntax parent
+            && node != parent.Initializers.First()
+        )
+        {
+            docs.Add(ExtraNewLines.Print(node));
+        }
+
         if (node.NameEquals != null)
         {
             docs.Add(Token.PrintWithSuffix(node.NameEquals.Name.Identifier, " ", context));

Src/CSharpier/SyntaxPrinter/SyntaxNodePrinters/AssignmentExpression.cs

@@ -4,9 +4,16 @@ internal static class AssignmentExpression
 {
     public static Doc Print(AssignmentExpressionSyntax node, FormattingContext context)
     {
+        Doc possibleNewLines = Doc.Null;
+
+        if (node.Parent is InitializerExpressionSyntax parent && node != parent.Expressions.First())
+        {
+            possibleNewLines = ExtraNewLines.Print(node);
+        }
+
         return RightHandSide.Print(
             node,
-            Doc.Concat(Node.Print(node.Left, context), " "),
+            Doc.Concat(possibleNewLines, Node.Print(node.Left, context), " "),
             Token.Print(node.OperatorToken, context),
             node.Right,
             context