PY-14234 Fix false positive when underscored module imported inside the package

python/src/com/jetbrains/python/inspections/PyProtectedMemberInspection.java

@@ -21,6 +21,7 @@ import com.intellij.codeInspection.ProblemHighlightType;
 import com.intellij.codeInspection.ProblemsHolder;
 import com.intellij.codeInspection.ui.MultipleCheckboxOptionsPanel;
 import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.psi.PsiDirectory;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiElementVisitor;
 import com.intellij.psi.PsiReference;
@@ -85,8 +86,18 @@ public class PyProtectedMemberInspection extends PyInspection {
       if (!(statement instanceof PyFromImportStatement)) return;
       final PyReferenceExpression importReferenceExpression = node.getImportReferenceExpression();
       final PyReferenceExpression importSource = ((PyFromImportStatement)statement).getImportSource();
-      if (importReferenceExpression != null && importSource != null)
+      if (importReferenceExpression != null && importSource != null && !isImportFromTheSamePackage(importSource)) {
         checkReference(importReferenceExpression, importSource);
+      }
+    }
+
+    private boolean isImportFromTheSamePackage(PyReferenceExpression importSource) {
+      PsiDirectory directory = importSource.getContainingFile().getContainingDirectory();
+      if (PyUtil.isPackage(directory, true, importSource.getContainingFile()) &&
+          directory.getName().equals(importSource.getName())) {
+        return true;
+      }
+      return false;
     }
 
     @Override

python/testData/inspections/PyProtectedMemberInspection/importFromTheSamePackage/my_package/_package_internal_module.py

@@ -0,0 +1,2 @@
+def very_smart_func(param):
+    return None

python/testData/inspections/PyProtectedMemberInspection/importFromTheSamePackage/my_package/my_public_module.py

@@ -0,0 +1,3 @@
+from my_package import _package_internal_module # False positive here
+
+_package_internal_module.very_smart_func("spam")

python/testSrc/com/jetbrains/python/inspections/PyProtectedMemberInspectionTest.java

@@ -69,6 +69,15 @@ public class PyProtectedMemberInspectionTest extends PyTestCase {
     myFixture.checkHighlighting(false, false, true);
   }
 
+  //PY-14234
+  public void testImportFromTheSamePackage() {
+    String path = getTestName(true);
+    myFixture.copyDirectoryToProject(path + "/my_package", "./my_package");
+    myFixture.configureByFile("/my_package/my_public_module.py");
+    myFixture.enableInspections(PyProtectedMemberInspection.class);
+    myFixture.checkHighlighting(false, false, true);
+  }
+
   public void testModule() {
     myFixture.configureByFiles(getTestName(true) + ".py", "tmp.py");
     myFixture.enableInspections(PyProtectedMemberInspection.class);