PY-84469 Consider ClassVar when matching protocol and a concrete class

GitOrigin-RevId: 76af969cfe9318049f02dc7f6bdd03fe20a9504f

python/python-psi-api/src/com/jetbrains/python/codeInsight/PyCustomMember.java

@@ -38,6 +38,8 @@ public class PyCustomMember extends UserDataHolderBase {
   private final PsiElement myTarget;
   private PyPsiPath myPsiPath;
 
+  private boolean myIsClassVar = false;
+
   boolean myFunction = false;
 
   /**
@@ -243,6 +245,16 @@ public class PyCustomMember extends UserDataHolderBase {
     return myFunction;
   }
 
+
+  public PyCustomMember asClassVar() {
+    myIsClassVar = true;
+    return this;
+  }
+
+  public boolean isClassVar() {
+    return myIsClassVar;
+  }
+
   /**
    * Checks if some reference points to this element
    *

python/python-psi-impl/resources/messages/PyPsiBundle.properties

@@ -1101,6 +1101,8 @@ INSP.protocol.newtype.cannot.be.used.with.protocol.classes=NewType cannot be use
 INSP.protocol.element.type.incompatible.with.protocol=Type of ''{0}'' is incompatible with ''{1}''
 INSP.protocol.cannot.instantiate.protocol.class=Cannot instantiate protocol class ''{0}''
 INSP.protocol.element.type.not.writable=''{0}'' is writable in protocol ''{1}''
+INSP.protocol.element.type.not.classvar=Cannot override class variable from protocol ''{0}'' with instance variable
+INSP.protocol.element.type.not.instancevar=Cannot override instance variable from protocol ''{0}'' with class variable
 
 # PyShadowingBuiltinsInspection
 INSP.NAME.shadowing.builtins=Shadowing built-in names

python/python-psi-impl/src/com/jetbrains/python/codeInsight/PyDataclassClassMembersProvider.java

@@ -51,7 +51,7 @@ public final class PyDataclassClassMembersProvider extends PyClassMembersProvide
       if (hasAttrs) {
         PyBuiltinCache builtinCache = PyBuiltinCache.getInstance(pyClass);
         PyClass objectClass = builtinCache.getClass(PyNames.OBJECT);
-        result.add(new PyCustomMember("__attrs_attrs__", objectClass));
+        result.add(new PyCustomMember("__attrs_attrs__", objectClass).asClassVar());
       }
 
       return CachedValueProvider.Result.create(result, PsiModificationTracker.MODIFICATION_COUNT);

python/python-psi-impl/src/com/jetbrains/python/psi/types/PyClassTypeImpl.java

@@ -17,6 +17,7 @@ import com.jetbrains.python.codeInsight.PyCustomMember;
 import com.jetbrains.python.codeInsight.PyCustomMemberUtils;
 import com.jetbrains.python.codeInsight.controlflow.ScopeOwner;
 import com.jetbrains.python.codeInsight.dataflow.scope.ScopeUtil;
+import com.jetbrains.python.codeInsight.typing.PyTypingTypeProvider;
 import com.jetbrains.python.psi.*;
 import com.jetbrains.python.psi.impl.*;
 import com.jetbrains.python.psi.impl.references.PyReferenceImpl;
@@ -607,7 +608,12 @@ public class PyClassTypeImpl extends UserDataHolderBase implements PyClassType {
             type = resolveContext.getTypeEvalContext().getType(typedElement);
           }
 
-          result.add(new PyTypeMember(element, type));
+          boolean isClassVar = false;
+          if (element instanceof PyAnnotationOwner && element instanceof PyTypeCommentOwner) {
+            isClassVar =
+              PyTypingTypeProvider.isClassVar((PyAnnotationOwner & PyTypeCommentOwner)element, resolveContext.getTypeEvalContext());
+          }
+          result.add(new PyTypeMember(element, type, isClassVar));
         }
       }
       return true;
@@ -689,12 +695,16 @@ public class PyClassTypeImpl extends UserDataHolderBase implements PyClassType {
 
     return ContainerUtil.map(results, result -> {
       PsiElement element = result.getElement();
+      boolean isClassVar = false;
+      if (element instanceof PyAnnotationOwner && element instanceof PyTypeCommentOwner) {
+        isClassVar = PyTypingTypeProvider.isClassVar((PyAnnotationOwner & PyTypeCommentOwner)element, context.getTypeEvalContext());
+      }
       if (element instanceof PyTypedElement typedElement) {
         return new PyTypeMember(typedElement,
-                                context.getTypeEvalContext().getType(typedElement), typedElement, typedElement, typedElement);
+                                context.getTypeEvalContext().getType(typedElement), isClassVar);
       }
       else {
-        return new PyTypeMember(element, null, element, element, element);
+        return new PyTypeMember(element, null, isClassVar);
       }
     });
   }

python/python-psi-impl/src/com/jetbrains/python/psi/types/PyTypeChecker.java

@@ -596,6 +596,12 @@ public final class PyTypeChecker {
         if (protocolMember.isDeletable() && !subclassElementMember.isDeletable()) {
           return false;
         }
+        boolean isProtocolMemberClassVar = protocolMember.isClassVar();
+        boolean isSubclassMemberClassVar = subclassElementMember.isClassVar();
+        if (isSubclassMemberClassVar != isProtocolMemberClassVar) {
+          return false;
+        }
+
         PyType subclassElementType = dropSelfIfNeeded(actual, subclassElementMember.getType(), matchContext.context);
         subclassElementType = substitute(subclassElementType, substitutions, matchContext.context);
         boolean matched = match(protocolElementType, subclassElementType, protocolContext).orElse(true);