SONARPY-1887 Resolve the fact that a class has a metaclass across its type hierarchy (#1811)

Author: maksim-grebeniuk-sonarsource

python-checks/src/test/resources/checks/nonCallableCalled.py

@@ -84,8 +84,7 @@ class Factory: ...
   class Base(metaclass=Factory): ...
   class A(Base): ...
   a = A()
-  # TODO: resolve type hierarchy and metaclasses
-  a() # Noncompliant
+  a()
 
 
 def decorators():

python-frontend/src/main/java/org/sonar/python/types/v2/ClassType.java

@@ -148,7 +148,12 @@ public TriBool hasMember(String memberName) {
   }
 
   public boolean hasMetaClass() {
-    return !this.metaClasses.isEmpty();
+    return !this.metaClasses.isEmpty() ||
+           this.superClasses()
+             .stream()
+             .filter(ClassType.class::isInstance)
+             .map(ClassType.class::cast)
+             .anyMatch(ClassType::hasMetaClass);
   }
 
   public TriBool instancesHaveMember(String memberName) {

python-frontend/src/test/java/org/sonar/python/semantic/v2/TypeInferenceV2Test.java

@@ -1185,6 +1185,47 @@ def f():
       .isEqualTo("int");
   }
 
+  @Test
+  void inferClassHierarchyHasMetaClass() {
+    var root = inferTypes("""
+      class CustomMetaClass:
+        ...
+      
+      class ParentClass(metaclass=CustomMetaClass):
+        ...
+      
+      class ChildClass(ParentClass):
+        ...
+      
+      def f():
+        a = ChildClass()
+        a
+      """);
+
+
+    var childClassType = TreeUtils.firstChild(root.statements().statements().get(2), ClassDef.class::isInstance)
+      .map(ClassDef.class::cast)
+      .map(ClassDef::name)
+      .map(Expression::typeV2)
+      .map(ClassType.class::cast)
+      .get();
+
+    Assertions.assertThat(childClassType.hasMetaClass()).isTrue();
+
+    var aType = TreeUtils.firstChild(root.statements().statements().get(3), ExpressionStatement.class::isInstance)
+      .map(ExpressionStatement.class::cast)
+      .flatMap(expressionStatement -> TreeUtils.firstChild(expressionStatement, Name.class::isInstance))
+      .map(Name.class::cast)
+      .map(Expression::typeV2)
+      .get();
+
+    Assertions.assertThat(aType)
+      .isNotNull()
+      .isNotEqualTo(PythonType.UNKNOWN)
+      .extracting(PythonType::unwrappedType)
+      .isSameAs(childClassType);
+  }
+
   private static FileInput inferTypes(String lines) {
     return inferTypes(lines, new HashMap<>());
   }