Setting to remove braces from single-line blocks

Underanalyzer/Decompiler/AST/IASTNode.cs

@@ -15,4 +15,9 @@ public interface IASTNode<T>
     /// Prints this node using the provided printer.
     /// </summary>
     public void Print(ASTPrinter printer);
+
+    /// <summary>
+    /// Calculates and returns whether the node will require multiple lines when printed.
+    /// </summary>
+    public bool RequiresMultipleLines(ASTPrinter printer);
 }

Underanalyzer/Decompiler/AST/Nodes/ArrayInitNode.cs

@@ -49,6 +49,18 @@ public void Print(ASTPrinter printer)
         printer.Write(']');
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        for (int i = 0; i < Elements.Count; i++)
+        {
+            if (Elements[i].RequiresMultipleLines(printer))
+            {
+                return true;
+            }
+        }
+        return false;
+    }
+
     public IExpressionNode ResolveMacroType(ASTCleaner cleaner, IMacroType type)
     {
         if (type is IMacroTypeArrayInit typeArrayInit)

Underanalyzer/Decompiler/AST/Nodes/AssetReferenceNode.cs

@@ -1,4 +1,6 @@
-namespace Underanalyzer.Decompiler.AST;
+using System.Xml.Linq;
+
+namespace Underanalyzer.Decompiler.AST;
 
 /// <summary>
 /// Represents an asset reference in the AST.
@@ -33,6 +35,11 @@ public IExpressionNode Clean(ASTCleaner cleaner)
         return this;
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return false;
+    }
+
     public void Print(ASTPrinter printer)
     {
         string assetName = printer.Context.GameContext.GetAssetName(AssetType, AssetId);

Underanalyzer/Decompiler/AST/Nodes/AssignNode.cs

@@ -266,4 +266,9 @@ public void Print(ASTPrinter printer)
                 break;
         }
     }
+
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return Variable.RequiresMultipleLines(printer) || Value.RequiresMultipleLines(printer);
+    }
 }

Underanalyzer/Decompiler/AST/Nodes/BinaryNode.cs

@@ -156,6 +156,11 @@ public void Print(ASTPrinter printer)
         }
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return Left.RequiresMultipleLines(printer) || Right.RequiresMultipleLines(printer);
+    }
+
     public IExpressionNode ResolveMacroType(ASTCleaner cleaner, IMacroType type)
     {
         bool didAnything = false;

Underanalyzer/Decompiler/AST/Nodes/BlockLocalVarDeclNode.cs

@@ -32,4 +32,9 @@ public void Print(ASTPrinter printer)
             }
         }
     }
+
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return false;
+    }
 }

Underanalyzer/Decompiler/AST/Nodes/BlockNode.cs

@@ -270,6 +270,45 @@ public void Print(ASTPrinter printer)
         printer.PopFragmentContext();
     }
 
+    public void PrintSingleLine(ASTPrinter printer)
+    {
+        printer.PushFragmentContext(FragmentContext);
+
+        printer.EndLine();
+        printer.Indent();
+        printer.StartLine();
+        if (Children.Count != 1)
+        {
+            throw new DecompilerException("Expected only one child node when printing on single line");
+        }
+        Children[0].Print(printer);
+        if (Children[0].SemicolonAfter)
+        {
+            printer.Semicolon();
+        }
+        printer.Dedent();
+
+        printer.PopFragmentContext();
+    }
+
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        // If we have more than one child node, or zero child nodes, we need multiple lines
+        if (Children.Count > 1 || Children.Count == 0)
+        {
+            return true;
+        }
+
+        // If our single child needs multiple lines, so do we
+        if (Children[0].RequiresMultipleLines(printer))
+        {
+            return true;
+        }
+
+        // Other basic cases: all switch statements, and all struct initializations
+        return PartOfSwitch || printer.StructArguments is not null;
+    }
+
     /// <summary>
     /// Adds a block-level local variable declaration node to the top of this block.
     /// </summary>

Underanalyzer/Decompiler/AST/Nodes/BooleanNode.cs

@@ -32,6 +32,11 @@ public void Print(ASTPrinter printer)
         printer.Write(Value ? "true" : "false");
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return false;
+    }
+
     public IExpressionNode ResolveMacroType(ASTCleaner cleaner, IMacroType type)
     {
         if (type is IMacroTypeConditional conditional)

Underanalyzer/Decompiler/AST/Nodes/BreakNode.cs

@@ -15,4 +15,9 @@ public void Print(ASTPrinter printer)
     {
         printer.Write("break");
     }
+
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return false;
+    }
 }

Underanalyzer/Decompiler/AST/Nodes/ConditionalNode.cs

@@ -79,6 +79,13 @@ public void Print(ASTPrinter printer)
         }
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return Condition.RequiresMultipleLines(printer) || 
+               True.RequiresMultipleLines(printer) || 
+               False.RequiresMultipleLines(printer);
+    }
+
     public IExpressionNode ResolveMacroType(ASTCleaner cleaner, IMacroType type)
     {
         if (type is IMacroTypeConditional conditional)

Underanalyzer/Decompiler/AST/Nodes/ContinueNode.cs

@@ -15,4 +15,9 @@ public void Print(ASTPrinter printer)
     {
         printer.Write("continue");
     }
+
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return false;
+    }
 }

Underanalyzer/Decompiler/AST/Nodes/DoUntilLoopNode.cs

@@ -40,20 +40,34 @@ public IStatementNode Clean(ASTCleaner cleaner)
     public void Print(ASTPrinter printer)
     {
         printer.Write("do");
-        if (printer.Context.Settings.OpenBlockBraceOnSameLine)
+        if (printer.Context.Settings.RemoveSingleLineBlockBraces && !Body.RequiresMultipleLines(printer))
         {
-            printer.Write(' ');
-            Body.Print(printer);
-            printer.Write(' ');
+            Body.PrintSingleLine(printer);
+            printer.EndLine();
+            printer.StartLine();
         }
         else
         {
-            Body.Print(printer);
-            printer.EndLine();
-            printer.StartLine();
+            if (printer.Context.Settings.OpenBlockBraceOnSameLine)
+            {
+                printer.Write(' ');
+                Body.Print(printer);
+                printer.Write(' ');
+            }
+            else
+            {
+                Body.Print(printer);
+                printer.EndLine();
+                printer.StartLine();
+            }
         }
         printer.Write("until (");
         Condition.Print(printer);
         printer.Write(')');
     }
+
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return true;
+    }
 }

Underanalyzer/Decompiler/AST/Nodes/DoubleNode.cs

@@ -115,6 +115,11 @@ public void Print(ASTPrinter printer)
         printer.Write(resultStr);
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return false;
+    }
+
     public IExpressionNode ResolveMacroType(ASTCleaner cleaner, IMacroType type)
     {
         if (type is IMacroTypeConditional conditional)

Underanalyzer/Decompiler/AST/Nodes/EnumDeclNode.cs

@@ -89,6 +89,11 @@ public void Print(ASTPrinter printer)
         printer.CloseBlock();
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return true;
+    }
+
     /// <summary>
     /// Generates enum declarations for the given context, returning a modified AST.
     /// </summary>

Underanalyzer/Decompiler/AST/Nodes/EnumValueNode.cs

@@ -62,6 +62,11 @@ public void Print(ASTPrinter printer)
         }
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return false;
+    }
+
     public IExpressionNode ResolveMacroType(ASTCleaner cleaner, IMacroType type)
     {
         if (type is IMacroTypeInt64 type64)

Underanalyzer/Decompiler/AST/Nodes/ExitNode.cs

@@ -39,4 +39,9 @@ public void Print(ASTPrinter printer)
         // TODO: check if we're inside of a function (or script in GMS2) and use "return" instead
         printer.Write("exit");
     }
+
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return false;
+    }
 }

Underanalyzer/Decompiler/AST/Nodes/ForLoopNode.cs

@@ -118,10 +118,22 @@ public void Print(ASTPrinter printer)
         }
         printer.Write(')');
 
-        if (printer.Context.Settings.OpenBlockBraceOnSameLine)
+        if (printer.Context.Settings.RemoveSingleLineBlockBraces && !Body.RequiresMultipleLines(printer))
         {
-            printer.Write(' ');
+            Body.PrintSingleLine(printer);
         }
-        Body.Print(printer);
+        else
+        {
+            if (printer.Context.Settings.OpenBlockBraceOnSameLine)
+            {
+                printer.Write(' ');
+            }
+            Body.Print(printer);
+        }
+    }
+
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return true;
     }
 }

Underanalyzer/Decompiler/AST/Nodes/FunctionCallNode.cs

@@ -138,6 +138,18 @@ public void Print(ASTPrinter printer)
         printer.Write(')');
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        foreach (IExpressionNode arg in Arguments)
+        {
+            if (arg.RequiresMultipleLines(printer))
+            {
+                return true;
+            }
+        }
+        return false;
+    }
+
     public IMacroType GetExpressionMacroType(ASTCleaner cleaner)
     {
         return cleaner.GlobalMacroResolver.ResolveReturnValueType(cleaner, Function.Name.Content);

Underanalyzer/Decompiler/AST/Nodes/FunctionDeclNode.cs

@@ -225,6 +225,11 @@ public void Print(ASTPrinter printer)
         Body.Print(printer);
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return true;
+    }
+
     public IExpressionNode ResolveMacroType(ASTCleaner cleaner, IMacroType type)
     {
         if (type is IMacroTypeConditional conditional)

Underanalyzer/Decompiler/AST/Nodes/FunctionReferenceNode.cs

@@ -35,6 +35,11 @@ public void Print(ASTPrinter printer)
         printer.Write(printer.LookupFunction(Function));
     }
 
+    public bool RequiresMultipleLines(ASTPrinter printer)
+    {
+        return false;
+    }
+
     public IExpressionNode ResolveMacroType(ASTCleaner cleaner, IMacroType type)
     {
         if (type is IMacroTypeConditional conditional)