Fix crash upon adding variable in the plan editor with empty default name

Also default to float when expected type is not specified.

blackboard/blackboard_plan.cpp

@@ -434,7 +434,7 @@ void BlackboardPlan::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("sync_with_base_plan"), &BlackboardPlan::sync_with_base_plan);
 	ClassDB::bind_method(D_METHOD("set_parent_scope_plan_provider", "callable"), &BlackboardPlan::set_parent_scope_plan_provider);
 	ClassDB::bind_method(D_METHOD("get_parent_scope_plan_provider"), &BlackboardPlan::get_parent_scope_plan_provider);
-	ClassDB::bind_method(D_METHOD("create_blackboard", "node", "parent_scope"), &BlackboardPlan::create_blackboard);
+	ClassDB::bind_method(D_METHOD("create_blackboard", "node", "parent_scope"), &BlackboardPlan::create_blackboard, DEFVAL(Ref<Blackboard>()));
 	ClassDB::bind_method(D_METHOD("populate_blackboard", "blackboard", "overwrite", "node"), &BlackboardPlan::populate_blackboard);
 
 	// To avoid cluttering the member namespace, we do not export unnecessary properties in this class.

doc/source/classes/class_blackboardplan.rst

@@ -35,7 +35,7 @@ Methods
    :widths: auto
 
    +---------------------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------+
-   | :ref:`Blackboard<class_Blackboard>`         | :ref:`create_blackboard<class_BlackboardPlan_method_create_blackboard>` **(** Node node, :ref:`Blackboard<class_Blackboard>` parent_scope **)**                   |
+   | :ref:`Blackboard<class_Blackboard>`         | :ref:`create_blackboard<class_BlackboardPlan_method_create_blackboard>` **(** Node node, :ref:`Blackboard<class_Blackboard>` parent_scope=null **)**              |
    +---------------------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------+
    | :ref:`BlackboardPlan<class_BlackboardPlan>` | :ref:`get_base_plan<class_BlackboardPlan_method_get_base_plan>` **(** **)** |const|                                                                               |
    +---------------------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------+
@@ -87,7 +87,7 @@ Method Descriptions
 
 .. rst-class:: classref-method
 
-:ref:`Blackboard<class_Blackboard>` **create_blackboard** **(** Node node, :ref:`Blackboard<class_Blackboard>` parent_scope **)**
+:ref:`Blackboard<class_Blackboard>` **create_blackboard** **(** Node node, :ref:`Blackboard<class_Blackboard>` parent_scope=null **)**
 
 Constructs a new instance of a :ref:`Blackboard<class_Blackboard>` using this plan. If ``NodePath`` prefetching is enabled, ``node`` will be used to retrieve node instances for ``NodePath`` variables and substitute their values.
 

doc_classes/BlackboardPlan.xml

@@ -11,7 +11,7 @@
 		<method name="create_blackboard">
 			<return type="Blackboard" />
 			<param index="0" name="node" type="Node" />
-			<param index="1" name="parent_scope" type="Blackboard" />
+			<param index="1" name="parent_scope" type="Blackboard" default="null" />
 			<description>
 				Constructs a new instance of a [Blackboard] using this plan. If [NodePath] prefetching is enabled, [param node] will be used to retrieve node instances for [NodePath] variables and substitute their values.
 			</description>

editor/blackboard_plan_editor.cpp

@@ -48,7 +48,7 @@ void BlackboardPlanEditor::_add_var() {
 	ERR_FAIL_NULL(plan);
 
 	int suffix = 1;
-	StringName var_name = default_var_name;
+	StringName var_name = default_var_name == StringName() ? "var" : default_var_name;
 	while (plan->has_var(var_name)) {
 		suffix += 1;
 		var_name = String(default_var_name) + itos(suffix);

editor/editor_property_variable_name.cpp

@@ -106,7 +106,8 @@ void EditorPropertyVariableName::_status_pressed() {
 	ERR_FAIL_NULL(plan);
 	if (!plan->has_var(name_edit->get_text())) {
 		BlackboardPlanEditor::get_singleton()->set_defaults(name_edit->get_text(),
-				expected_type, default_hint, default_hint_string, default_value);
+				expected_type == Variant::NIL ? Variant::FLOAT : expected_type,
+				default_hint, default_hint_string, default_value);
 	}
 	BlackboardPlanEditor::get_singleton()->edit_plan(plan);
 	BlackboardPlanEditor::get_singleton()->popup_centered();

editor/editor_property_variable_name.h

@@ -77,7 +77,7 @@ public:
 	virtual void _update_property() override;
 #endif
 
-	void setup(const Ref<BlackboardPlan> &p_plan, bool p_allow_empty, Variant::Type p_type = Variant::FLOAT, PropertyHint p_hint = PROPERTY_HINT_NONE, String p_hint_string = "", Variant p_default_value = Variant());
+	void setup(const Ref<BlackboardPlan> &p_plan, bool p_allow_empty, Variant::Type p_type = Variant::NIL, PropertyHint p_hint = PROPERTY_HINT_NONE, String p_hint_string = "", Variant p_default_value = Variant());
 	EditorPropertyVariableName();
 };