added in support for YarnNodeParameter attribute.

This allows for tagging a string as part of a yarn action as being a node.
This doesn't do anything at run time but as part of editing the LSP now knows to offer autocomplete and warnings if the values of the parameter aren't a node in the project.

Author: McJones

Editor/Analysis/Action.cs

@@ -138,6 +138,8 @@ public struct Parameter
         public string? DefaultValueString;
         public bool IsParamsArray;
 
+        public AttributeData[]? Attributes;
+
         public readonly string? YarnTypeString => Type.GetYarnTypeString();
     }
 
@@ -287,7 +289,17 @@ public string ToJSON()
                 }
                 else
                 {
-                    paramObject["Type"] = p.YarnTypeString;
+                    // there is one special case of the regular types
+                    // if the parameter has the YarnNodeParameterAttribute on it then we want to say it's a node and not a string
+                    var isANodeType = p.Attributes?.Count(a => a.AttributeClass?.Name == "YarnNodeParameterAttribute") > 0;
+                    if (isANodeType && p.Type.SpecialType == SpecialType.System_String)
+                    {
+                        paramObject["Type"] = "node";
+                    }
+                    else
+                    {
+                        paramObject["Type"] = p.YarnTypeString;
+                    }
                 }
 
                 return paramObject;

Editor/Analysis/Analyser.cs

@@ -865,6 +865,16 @@ private static List<Parameter> GetParams(IMethodSymbol symbol, XElement? documen
             {
                 logger?.WriteLine($"\t{param.Name} is a {param.Type.ToDisplayString()}");
 
+                List<AttributeData> attributes = new List<AttributeData>();
+                foreach (var attribute in param.GetAttributes())
+                {
+                    if (attribute.AttributeClass?.BaseType?.Name == "YarnParameterAttribute")
+                    {
+                        logger?.WriteLine($"\t\tattribute: {attribute.AttributeClass?.Name}");
+                        attributes.Add(attribute);
+                    }
+                }
+
                 parameterDocumentation.TryGetValue(param.Name, out var paramDoc);
                 var p = new Parameter
                 {
@@ -873,6 +883,7 @@ private static List<Parameter> GetParams(IMethodSymbol symbol, XElement? documen
                     Type = param.Type,
                     Description = paramDoc,
                     IsParamsArray = param.IsParams,
+                    Attributes = attributes.Count() == 0 ? null : attributes.ToArray(),
                     DefaultValueString = param.HasExplicitDefaultValue ? param.ExplicitDefaultValue?.ToString() : null,
                 };
                 parameters.Add(p);

Runtime/Commands/YarnNodeParameterAttribute.cs

@@ -0,0 +1,15 @@
+/*
+Yarn Spinner is licensed to you under the terms found in the file LICENSE.md.
+*/
+
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+#nullable enable
+
+namespace Yarn.Unity.Attributes
+{
+    public class YarnNodeParameterAttribute: YarnParameterAttribute {}
+}

Runtime/Commands/YarnNodeParameterAttribute.cs.meta

@@ -0,0 +1,18 @@
+/*
+Yarn Spinner is licensed to you under the terms found in the file LICENSE.md.
+*/
+
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+#nullable enable
+
+namespace Yarn.Unity.Attributes
+{
+    [AttributeUsage(AttributeTargets.Parameter, Inherited = false)]
+    public abstract class YarnParameterAttribute : Attribute
+    {
+    }
+}