From aea9e8688f1116680c29d4e17986215ce0d2f0b2 Mon Sep 17 00:00:00 2001
From: Mikhail Golubev <mikhail.golubev@jetbrains.com>
Date: Wed, 22 Oct 2025 17:20:30 +0300
Subject: [PATCH] [python] PY-85031 Use PyAstNamedParameter.isSelf when
 reporting legacy positional-only parameters

It correctly takes into account the first argument of `__new__` that is also implicit,
and thus should be excluded when reporting positional-only parameters following
non-positional-only ones.

GitOrigin-RevId: abf09c6be5e49c21c12264d22bf63a51018fdcd6
---
 .../com/jetbrains/python/psi/impl/PyFunctionImpl.java    | 9 ---------
 .../validation/PyParameterListAnnotatorVisitor.java      | 4 +---
 .../highlighting/historicalPositionalOnlyParameters.py   | 3 ++-
 3 files changed, 3 insertions(+), 13 deletions(-)

diff --git a/python/python-psi-impl/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java b/python/python-psi-impl/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java
index 2215d2a8c6aa..ddbefd0d82dc 100644
--- a/python/python-psi-impl/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java
+++ b/python/python-psi-impl/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java
@@ -790,15 +790,6 @@ public class PyFunctionImpl extends PyBaseElementImpl<PyFunctionStub> implements
     return getStubOrPsiChild(PyStubElementTypes.ANNOTATION);
   }
 
-  /**
-   * is `function` a method or a classmethod
-   */
-  public static boolean isMethod(PyFunction function) {
-    final var isMethod = ScopeUtil.getScopeOwner(function) instanceof PyClass;
-    final var modifier = function.getModifier();
-    return (isMethod && modifier == null) || modifier == CLASSMETHOD;
-  }
-
   /**
    * @param self should be this
    */
diff --git a/python/python-psi-impl/src/com/jetbrains/python/validation/PyParameterListAnnotatorVisitor.java b/python/python-psi-impl/src/com/jetbrains/python/validation/PyParameterListAnnotatorVisitor.java
index 617fd0ee286b..b65d43f96179 100644
--- a/python/python-psi-impl/src/com/jetbrains/python/validation/PyParameterListAnnotatorVisitor.java
+++ b/python/python-psi-impl/src/com/jetbrains/python/validation/PyParameterListAnnotatorVisitor.java
@@ -19,7 +19,6 @@ import com.intellij.lang.annotation.HighlightSeverity;
 import com.jetbrains.python.PyPsiBundle;
 import com.jetbrains.python.psi.*;
 import com.jetbrains.python.psi.impl.ParamHelper;
-import com.jetbrains.python.psi.impl.PyFunctionImpl;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.HashSet;
@@ -38,7 +37,6 @@ public class PyParameterListAnnotatorVisitor extends PyElementVisitor {
   @Override
   public void visitPyParameterList(final @NotNull PyParameterList paramlist) {
     final LanguageLevel languageLevel = LanguageLevel.forElement(paramlist);
-    final var hasImplicit = paramlist.getParent() instanceof PyFunction function && PyFunctionImpl.isMethod(function);
 
     ParamHelper.walkDownParamArray(
       paramlist.getParameters(),
@@ -55,7 +53,7 @@ public class PyParameterListAnnotatorVisitor extends PyElementVisitor {
         @Override
         public void visitNamedParameter(PyNamedParameter parameter, boolean first, boolean last) {
           final var name = parameter.getName();
-          if (!hadKeyword && name != null && !(hasImplicit && first) && !isPrivate(name)) {
+          if (!hadKeyword && name != null && !parameter.isSelf() && !isPrivate(name)) {
             hadKeyword = true;
           }
           else if (hadKeyword && !hadPositionalContainer && !hadSingleStar && name != null && !hadSlash && isPrivate(name)) {
diff --git a/python/testData/highlighting/historicalPositionalOnlyParameters.py b/python/testData/highlighting/historicalPositionalOnlyParameters.py
index d16df2b8969a..f023489d9e09 100644
--- a/python/testData/highlighting/historicalPositionalOnlyParameters.py
+++ b/python/testData/highlighting/historicalPositionalOnlyParameters.py
@@ -15,4 +15,5 @@ class A:
     @staticmethod
     def s1(__b): pass
     @staticmethod
-    def s1(a, <warning descr="Positional-only parameter follows parameter that is not positional-only">__b</warning>): pass
\ No newline at end of file
+    def s1(a, <warning descr="Positional-only parameter follows parameter that is not positional-only">__b</warning>): pass
+    def __new__(cls, __b): pass
\ No newline at end of file