From fcefe43db929ef4c172410b2de140779f1e1dd2e Mon Sep 17 00:00:00 2001
From: Semyon Proshev <Semyon.Proshev@jetbrains.com>
Date: Thu, 30 Nov 2017 17:46:59 +0300
Subject: [PATCH] Improve ignoring access to namedtuple's protected members
 (PY-27148)

---
 .../PyProtectedMemberInspection.java          |  1 -
 .../stdlib/PyStdlibInspectionExtension.kt     | 26 +++++++++++++++++++
 .../PyProtectedMemberInspection/namedTuple.py | 18 +++++++++++--
 .../typingNamedTuple.py                       | 21 +++++++++++++++
 .../PyProtectedMemberInspectionTest.java      |  5 ++++
 5 files changed, 68 insertions(+), 3 deletions(-)
 create mode 100644 python/testData/inspections/PyProtectedMemberInspection/typingNamedTuple.py

diff --git a/python/src/com/jetbrains/python/inspections/PyProtectedMemberInspection.java b/python/src/com/jetbrains/python/inspections/PyProtectedMemberInspection.java
index f37b3b060618..777cc117bf4d 100644
--- a/python/src/com/jetbrains/python/inspections/PyProtectedMemberInspection.java
+++ b/python/src/com/jetbrains/python/inspections/PyProtectedMemberInspection.java
@@ -91,7 +91,6 @@ public class PyProtectedMemberInspection extends PyInspection {
     }
 
     private void checkReference(@NotNull final PyReferenceExpression node, @NotNull final PyExpression qualifier) {
-      if (myTypeEvalContext.getType(qualifier) instanceof PyNamedTupleType) return;
       final String name = node.getName();
       final List<LocalQuickFix> quickFixes = new ArrayList<>();
       quickFixes.add(new PyRenameElementQuickFix());
diff --git a/python/src/com/jetbrains/python/inspections/stdlib/PyStdlibInspectionExtension.kt b/python/src/com/jetbrains/python/inspections/stdlib/PyStdlibInspectionExtension.kt
index f9d4b3a9c2e1..a310283474ac 100644
--- a/python/src/com/jetbrains/python/inspections/stdlib/PyStdlibInspectionExtension.kt
+++ b/python/src/com/jetbrains/python/inspections/stdlib/PyStdlibInspectionExtension.kt
@@ -5,6 +5,7 @@ import com.intellij.psi.PsiReference
 import com.jetbrains.python.PyNames
 import com.jetbrains.python.codeInsight.stdlib.PyNamedTupleType
 import com.jetbrains.python.codeInsight.stdlib.PyStdlibClassMembersProvider
+import com.jetbrains.python.codeInsight.typing.PyTypingTypeProvider
 import com.jetbrains.python.inspections.PyInspectionExtension
 import com.jetbrains.python.psi.PyElement
 import com.jetbrains.python.psi.PyFunction
@@ -15,6 +16,10 @@ import com.jetbrains.python.psi.types.TypeEvalContext
 
 class PyStdlibInspectionExtension : PyInspectionExtension() {
 
+  companion object {
+    private val NAMEDTUPLE_SPECIAL_ATTRIBUTES = setOf("_make", "_asdict", "_replace", "_source", "_fields")
+  }
+
   override fun ignoreInitNewSignatures(original: PyFunction, complementary: PyFunction): Boolean {
     return PyNames.TYPE_ENUM == complementary.containingClass?.qualifiedName
   }
@@ -39,4 +44,25 @@ class PyStdlibInspectionExtension : PyInspectionExtension() {
 
     return false
   }
+
+  override fun ignoreProtectedSymbol(expression: PyReferenceExpression, context: TypeEvalContext): Boolean {
+    val qualifier = expression.qualifier
+
+    if (qualifier != null && expression.referencedName in NAMEDTUPLE_SPECIAL_ATTRIBUTES) {
+      val qualifierType = context.getType(qualifier)
+
+      if (qualifierType is PyNamedTupleType) {
+        return true
+      }
+
+      val isTypingNT: (PyClassLikeType?) -> Boolean =
+        { it is PyNamedTupleType || it != null && PyTypingTypeProvider.NAMEDTUPLE == it.classQName }
+
+      if (qualifierType is PyClassLikeType && qualifierType.getAncestorTypes(context).find(isTypingNT) != null) {
+        return true
+      }
+    }
+
+    return false
+  }
 }
\ No newline at end of file
diff --git a/python/testData/inspections/PyProtectedMemberInspection/namedTuple.py b/python/testData/inspections/PyProtectedMemberInspection/namedTuple.py
index 905088a1ba69..7dd33d20eb3a 100644
--- a/python/testData/inspections/PyProtectedMemberInspection/namedTuple.py
+++ b/python/testData/inspections/PyProtectedMemberInspection/namedTuple.py
@@ -1,6 +1,20 @@
 from collections import namedtuple
 
-i = namedtuple('Point', ['x', 'y'], verbose=True)
-i._replace( **{"a":"a"})
+
+class Cat1(namedtuple("Cat", "name age")):
+    pass
+c1 = Cat1("name", 5)
+print(c1._make)
+print(c1._asdict)
+print(c1._replace)
+print(c1._source)
+print(c1._fields)
 
 
+Cat2 = namedtuple("Cat2", "name age")
+c2 = Cat2("name", 5)
+print(c2._make)
+print(c2._asdict)
+print(c2._replace)
+print(c2._source)
+print(c2._fields)
\ No newline at end of file
diff --git a/python/testData/inspections/PyProtectedMemberInspection/typingNamedTuple.py b/python/testData/inspections/PyProtectedMemberInspection/typingNamedTuple.py
new file mode 100644
index 000000000000..a57c8a33a7ef
--- /dev/null
+++ b/python/testData/inspections/PyProtectedMemberInspection/typingNamedTuple.py
@@ -0,0 +1,21 @@
+from typing import NamedTuple
+
+
+class Cat1(NamedTuple):
+    name: str
+    age: int
+c1 = Cat1("name", 5)
+print(c1._make)
+print(c1._asdict)
+print(c1._replace)
+print(c1._source)
+print(c1._fields)
+
+
+Cat2 = NamedTuple("Cat2", name=str, age=int)
+c2 = Cat2("name", 5)
+print(c2._make)
+print(c2._asdict)
+print(c2._replace)
+print(c2._source)
+print(c2._fields)
\ No newline at end of file
diff --git a/python/testSrc/com/jetbrains/python/inspections/PyProtectedMemberInspectionTest.java b/python/testSrc/com/jetbrains/python/inspections/PyProtectedMemberInspectionTest.java
index 1a693d18402b..5292e09b2118 100644
--- a/python/testSrc/com/jetbrains/python/inspections/PyProtectedMemberInspectionTest.java
+++ b/python/testSrc/com/jetbrains/python/inspections/PyProtectedMemberInspectionTest.java
@@ -79,6 +79,11 @@ public class PyProtectedMemberInspectionTest extends PyInspectionTestCase {
     runWithLanguageLevel(LanguageLevel.PYTHON35, this::doMultiFileTest);
   }
 
+  // PY-27148
+  public void testTypingNamedTuple() {
+    runWithLanguageLevel(LanguageLevel.PYTHON36, this::doTest);
+  }
+
   @NotNull
   @Override
   protected Class<? extends PyInspection> getInspectionClass() {