feat: Add parameters to Signals.

Author: fuzzybinary

src/dart/godot_dart/lib/src/annotations/godot_script.dart

@@ -21,12 +21,21 @@ class GodotExport {
   const GodotExport({this.name});
 }
 
+@immutable
+class SignalArgument {
+  final String name;
+  final Type type;
+
+  const SignalArgument(this.name, this.type);
+}
+
 /// Annotate a Godot Signal
 @immutable
 class GodotSignal {
   final String signalName;
+  final List<SignalArgument> args;
 
-  const GodotSignal(this.signalName);
+  const GodotSignal(this.signalName, {this.args = const []});
 }
 
 /// Annotate a field that should be visible to the Godot property inspector

src/dart/godot_dart_build/lib/src/godot_script_generator.dart

@@ -155,8 +155,16 @@ class GodotScriptAnnotationGenerator
     final signalName = reader.read('signalName').stringValue;
     buffer.writeln('  name: \'$signalName\',');
 
-    // TODO: Signals that take parameters....
-    buffer.writeln('  args:  [],');
+    final signalArguments = reader.read('args').listValue;
+    buffer.writeln('  args:  [');
+    for (final arg in signalArguments) {
+      final argReader = ConstantReader(arg);
+      final argName = argReader.read('name').stringValue;
+      final argType = argReader.read('type').typeValue;
+      buffer.writeln(
+          '    PropertyInfo(name: \'${argName}\', typeInfo: ${_typeInfoForType(argType)}),');
+    }
+    buffer.writeln(']');
     buffer.write(')');
 
     return buffer.toString();