From a13764a6b7bbe4bc6d7aac09023fa49c009fc221 Mon Sep 17 00:00:00 2001
From: Morgan Bartholomew <morgan.bartholomew@jetbrains.com>
Date: Fri, 5 Sep 2025 11:56:19 +0000
Subject: [PATCH] [python] PY-81651 respect explicit `Any` on binary operators

Merge-request: IJ-MR-174645
Merged-by: Morgan Bartholomew <morgan.bartholomew@jetbrains.com>

GitOrigin-RevId: 9062f58b163d99f526f2bb0c3ebfa29039508f54
---
 .../psi/impl/PyBinaryExpressionImpl.java       | 18 ++++++++++--------
 .../ComparisonOperators.py                     |  2 +-
 .../com/jetbrains/python/Py3TypeTest.java      | 15 +++++++++++++++
 3 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/python/python-psi-impl/src/com/jetbrains/python/psi/impl/PyBinaryExpressionImpl.java b/python/python-psi-impl/src/com/jetbrains/python/psi/impl/PyBinaryExpressionImpl.java
index 5451d98720d9..09d53f29f2f5 100644
--- a/python/python-psi-impl/src/com/jetbrains/python/psi/impl/PyBinaryExpressionImpl.java
+++ b/python/python-psi-impl/src/com/jetbrains/python/psi/impl/PyBinaryExpressionImpl.java
@@ -68,15 +68,17 @@ public class PyBinaryExpressionImpl extends PyElementImpl implements PyBinaryExp
       return PyBuiltinCache.getInstance(this).getBoolType();
     }
     PyType callResultType = PyCallExpressionHelper.getCallType(this, context, key);
-    if (callResultType != null) {
-      boolean bothOperandsAreKnown = operandIsKnown(getLeftExpression(), context) && operandIsKnown(getRightExpression(), context);
-      // TODO requires weak union. See PyTypeCheckerInspectionTest#testBinaryExpressionWithUnknownOperand
-      return bothOperandsAreKnown ? callResultType : PyUnionType.createWeakType(callResultType);
+    if (callResultType == null) {
+      if (referencedName != null && PyNames.COMPARISON_OPERATORS.contains(referencedName)) {
+        // we don't know if it was explicit or not, so we form an unsafe union of Any and bool
+        // TODO: when { explicit Any -> Any, Unknown -> UnsafeUnion[bool | Any] }
+        return PyUnsafeUnionType.unsafeUnion(null, PyBuiltinCache.getInstance(this).getBoolType());
+      }
+      return null;
     }
-    if (referencedName != null && PyNames.COMPARISON_OPERATORS.contains(referencedName)) {
-      return PyBuiltinCache.getInstance(this).getBoolType();
-    }
-    return null;
+    boolean bothOperandsAreKnown = operandIsKnown(getLeftExpression(), context) && operandIsKnown(getRightExpression(), context);
+    // TODO requires weak union. See PyTypeCheckerInspectionTest#testBinaryExpressionWithUnknownOperand
+    return bothOperandsAreKnown ? callResultType : PyUnionType.createWeakType(callResultType);
   }
 
   private static boolean operandIsKnown(@Nullable PyExpression operand, @NotNull TypeEvalContext context) {
diff --git a/python/testData/inspections/PyTypeCheckerInspection/ComparisonOperators.py b/python/testData/inspections/PyTypeCheckerInspection/ComparisonOperators.py
index 3b745411b446..0f9b83515070 100644
--- a/python/testData/inspections/PyTypeCheckerInspection/ComparisonOperators.py
+++ b/python/testData/inspections/PyTypeCheckerInspection/ComparisonOperators.py
@@ -11,7 +11,7 @@ def test():
     c = C()
     f(<warning descr="Expected type 'str', got 'bool' instead">1 < 2</warning>)
     f(<warning descr="Expected type 'str', got 'bool' instead">o == o</warning>)
-    f(<warning descr="Expected type 'str', got 'bool' instead">o >= o</warning>)
+    f(o >= o)
     f(<warning descr="Expected type 'str', got 'bool' instead">'foo' > 'bar'</warning>)
     f(<warning descr="Expected type 'str', got 'bool' instead"><warning descr="Expected type 'int', got 'C' instead">c</warning> < 1</warning>)
     f(<warning descr="Expected type 'str', got 'List[Any]' instead">c > 1</warning>)
diff --git a/python/testSrc/com/jetbrains/python/Py3TypeTest.java b/python/testSrc/com/jetbrains/python/Py3TypeTest.java
index b512b53957a9..696c8396a105 100644
--- a/python/testSrc/com/jetbrains/python/Py3TypeTest.java
+++ b/python/testSrc/com/jetbrains/python/Py3TypeTest.java
@@ -1,6 +1,7 @@
 // Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.jetbrains.python;
 
+import com.intellij.idea.TestFor;
 import com.intellij.openapi.project.Project;
 import com.intellij.psi.PsiFile;
 import com.jetbrains.python.fixtures.PyTestCase;
@@ -3975,6 +3976,20 @@ public class Py3TypeTest extends PyTestCase {
       """);
   }
 
+  @TestFor(issues="PY-81651")
+  public void testEqWithAny() {
+    // the actual result is `Any`, but we don't have the technology yet
+    doTest("UnsafeUnion[Any, bool]", """
+      from typing import Any
+      
+      class A:
+          def __eq__(self, other) -> Any:
+            return "hello :)"
+
+      expr = A() == 1
+      """);
+  }
+
   private void doTest(final String expectedType, final String text) {
     myFixture.configureByText(PythonFileType.INSTANCE, text);
     final PyExpression expr = myFixture.findElementByText("expr", PyExpression.class);