validation: Disallow instantiating abstract classes

blueprintcompiler/gir.py

@@ -236,6 +236,10 @@ class Class(GirNode, GirType):
         self.own_properties = {child["name"]: Property(self, child) for child in xml.get_elements("property")}
         self.own_signals = {child["name"]: Signal(self, child) for child in xml.get_elements("glib:signal")}
 
+    @property
+    def abstract(self):
+        return self.xml["abstract"] == "1"
+
     @property
     def signature(self):
         result = f"class {self.container.name}.{self.name}"

blueprintcompiler/language/gobject_object.py

@@ -61,6 +61,14 @@ class Object(AstNode):
         if self.tokens["class_name"] and not self.tokens["ignore_gir"] and self.gir_ns is not None:
             self.root.gir.validate_class(self.tokens["class_name"], self.tokens["namespace"])
 
+    @validate("namespace", "class_name")
+    def not_abstract(self):
+        if self.gir_class is not None and self.gir_class.abstract:
+            raise CompileError(
+                f"{self.gir_class.full_name} can't be instantiated because it's abstract",
+                hints=[f"did you mean to use a subclass of {self.gir_class.full_name}?"]
+            )
+
     @property
     def gir_ns(self):
         if not self.tokens["ignore_gir"]:

blueprintcompiler/language/gtk_menu.py

@@ -33,7 +33,7 @@ class Menu(Object):
 
     @property
     def gir_class(self):
-        return self.root.gir.namespaces["Gtk"].lookup_type("Gio.MenuModel")
+        return self.root.gir.namespaces["Gtk"].lookup_type("Gio.Menu")
 
 
 class MenuAttribute(BaseAttribute):

blueprintcompiler/language/gtkbuilder_template.py

@@ -33,6 +33,10 @@ class Template(Object):
         ObjectContent,
     ]
 
+    @validate()
+    def not_abstract(self):
+        pass # does not apply to templates
+
     def emit_xml(self, xml: XmlEmitter):
         if self.gir_class:
             parent = self.gir_class.glib_type_name

tests/sample_errors/a11y_prop_dne.blp

@@ -1,6 +1,6 @@
 using Gtk 4.0;
 
-Widget {
+Button {
   accessibility {
     not_a_prop: "Hello, world!";
   }

tests/sample_errors/a11y_prop_obj_dne.blp

@@ -1,6 +1,6 @@
 using Gtk 4.0;
 
-Widget {
+Button {
   accessibility {
     labelled-by: not_an_object;
   }

tests/sample_errors/a11y_prop_type.blp

@@ -1,6 +1,6 @@
 using Gtk 4.0;
 
-Widget {
+Button {
   accessibility {
     orientation: 1;
   }

tests/sample_errors/abstract_class.blp

@@ -0,0 +1,4 @@
+using Gtk 4.0;
+
+template MyWidget : Gtk.Widget {}
+Gtk.Widget {}

tests/sample_errors/abstract_class.err

@@ -0,0 +1 @@
+4,1,10,Gtk.Widget can't be instantiated because it's abstract

tests/sample_errors/assign_inline_menu.err

@@ -1 +1 @@
-4,3,15,Cannot assign Gio.MenuModel to string
+4,3,15,Cannot assign Gio.Menu to string

tests/sample_errors/filters_in_non_file_filter.blp

@@ -1,6 +1,6 @@
 using Gtk 4.0;
 
-Widget {
+Button {
   mime-types []
   patterns []
   suffixes []

tests/sample_errors/filters_in_non_file_filter.err

@@ -1,3 +1,3 @@
-4,3,13,Gtk.Widget is not a Gtk.FileFilter, so it doesn't have file filter properties
+4,3,13,Gtk.Button is not a Gtk.FileFilter, so it doesn't have file filter properties
-5,3,11,Gtk.Widget is not a Gtk.FileFilter, so it doesn't have file filter properties
+5,3,11,Gtk.Button is not a Gtk.FileFilter, so it doesn't have file filter properties
-6,3,11,Gtk.Widget is not a Gtk.FileFilter, so it doesn't have file filter properties
+6,3,11,Gtk.Button is not a Gtk.FileFilter, so it doesn't have file filter properties

tests/sample_errors/obj_in_string_list.blp

@@ -6,4 +6,4 @@ StringList {
   ]
 }
 
-Widget id {}
+Button id {}

tests/sample_errors/obj_in_string_list.err

@@ -1 +1 @@
-5,5,2,Cannot assign Gtk.Widget to string
+5,5,2,Cannot assign Gtk.Button to string

tests/sample_errors/widgets_in_non_size_group.blp

@@ -1,5 +1,5 @@
 using Gtk 4.0;
 
-Widget {
+Button {
   widgets []
 }

tests/sample_errors/widgets_in_non_size_group.err

@@ -1 +1 @@
-4,3,7,Gtk.Widget is not a Gtk.SizeGroup, so it doesn't have size group properties
+4,3,7,Gtk.Button is not a Gtk.SizeGroup, so it doesn't have size group properties

tests/test_samples.py

@@ -164,6 +164,7 @@ class TestSamples(unittest.TestCase):
         self.assert_sample_error("a11y_prop_dne")
         self.assert_sample_error("a11y_prop_obj_dne")
         self.assert_sample_error("a11y_prop_type")
+        self.assert_sample_error("abstract_class")
         self.assert_sample_error("assign_inline_menu")
         self.assert_sample_error("action_widget_float_response")
         self.assert_sample_error("action_widget_have_no_id")