Prevent recomputation of superclasses during first call to isNewStyleClass

python/src/com/jetbrains/python/psi/impl/PyClassImpl.java

@@ -1059,8 +1059,7 @@ public class PyClassImpl extends PyBaseElementImpl<PyClassStub> implements PyCla
       }
       if (type instanceof PyClassType) {
         final PyClass pyClass = ((PyClassType)type).getPyClass();
-        if (pyClass == objClass) return true;
-        if (hasNewStyleMetaClass(pyClass)) {
+        if (pyClass == objClass || hasNewStyleMetaClass(pyClass)) {
           return true;
         }
       }
@@ -1310,7 +1309,7 @@ public class PyClassImpl extends PyBaseElementImpl<PyClassStub> implements PyCla
   @NotNull
   private List<PyClassLikeType> getOldStyleAncestorTypes(@NotNull TypeEvalContext context) {
     final List<PyClassLikeType> results = new ArrayList<PyClassLikeType>();
-    final List<PyClassLikeType> toProcess = new ArrayList<PyClassLikeType>();
+    final Deque<PyClassLikeType> toProcess = new LinkedList<PyClassLikeType>();
     final Set<PyClassLikeType> seen = new HashSet<PyClassLikeType>();
     final Set<PyClassLikeType> visited = new HashSet<PyClassLikeType>();
     final PyType thisType = context.getType(this);
@@ -1318,15 +1317,17 @@ public class PyClassImpl extends PyBaseElementImpl<PyClassStub> implements PyCla
       toProcess.add((PyClassLikeType)thisType);
     }
     while (!toProcess.isEmpty()) {
-      final PyClassLikeType currentType = toProcess.remove(0);
-      visited.add(currentType);
+      final PyClassLikeType currentType = toProcess.pollFirst();
+      if (!visited.add(currentType)) {
+        continue;
+      }
       for (PyClassLikeType superType : currentType.getSuperClassTypes(context)) {
         if (superType == null || !seen.contains(superType)) {
           results.add(superType);
           seen.add(superType);
         }
         if (superType != null && !visited.contains(superType)) {
-          toProcess.add(superType);
+          toProcess.addLast(superType);
         }
       }
     }

python/testData/codeInsight/classMRO/TangledInheritance.py

@@ -1,4 +1,5 @@
 
+
 class Class001(object):
     unique_attr = 1
 
@@ -82,9 +83,11 @@ class Class020(Class019, Class018, Class017):
 class Class021(Class020, Class019, Class018):
     unique_attr = 21
 
+
 class Class022(Class021, Class020, Class019):
     unique_attr = 22
 
+
 class Class023(Class022, Class021, Class020):
     unique_attr = 23
 
@@ -110,8 +113,289 @@ class Class028(Class027, Class026, Class025):
 
 
 class Class029(Class028, Class027, Class026):
-
     unique_attr = 29
 
+
 class Class030(Class029, Class028, Class027):
     unique_attr = 30
+
+
+class Class031(Class030, Class029, Class028):
+    unique_attr = 31
+
+
+class Class032(Class031, Class030, Class029):
+    unique_attr = 32
+
+
+class Class033(Class032, Class031, Class030):
+    unique_attr = 33
+
+
+class Class034(Class033, Class032, Class031):
+    unique_attr = 34
+
+
+class Class035(Class034, Class033, Class032):
+    unique_attr = 35
+
+
+class Class036(Class035, Class034, Class033):
+    unique_attr = 36
+
+
+class Class037(Class036, Class035, Class034):
+    unique_attr = 37
+
+
+class Class038(Class037, Class036, Class035):
+    unique_attr = 38
+
+
+class Class039(Class038, Class037, Class036):
+    unique_attr = 39
+
+
+class Class040(Class039, Class038, Class037):
+    unique_attr = 40
+
+
+class Class041(Class040, Class039, Class038):
+    unique_attr = 41
+
+
+class Class042(Class041, Class040, Class039):
+    unique_attr = 42
+
+
+class Class043(Class042, Class041, Class040):
+    unique_attr = 43
+
+
+class Class044(Class043, Class042, Class041):
+    unique_attr = 44
+
+
+class Class045(Class044, Class043, Class042):
+    unique_attr = 45
+
+
+class Class046(Class045, Class044, Class043):
+    unique_attr = 46
+
+
+class Class047(Class046, Class045, Class044):
+    unique_attr = 47
+
+
+class Class048(Class047, Class046, Class045):
+    unique_attr = 48
+
+
+class Class049(Class048, Class047, Class046):
+    unique_attr = 49
+
+
+class Class050(Class049, Class048, Class047):
+    unique_attr = 50
+
+
+class Class051(Class050, Class049, Class048):
+    unique_attr = 51
+
+
+class Class052(Class051, Class050, Class049):
+    unique_attr = 52
+
+
+class Class053(Class052, Class051, Class050):
+    unique_attr = 53
+
+
+class Class054(Class053, Class052, Class051):
+    unique_attr = 54
+
+
+class Class055(Class054, Class053, Class052):
+    unique_attr = 55
+
+
+class Class056(Class055, Class054, Class053):
+    unique_attr = 56
+
+
+class Class057(Class056, Class055, Class054):
+    unique_attr = 57
+
+
+class Class058(Class057, Class056, Class055):
+    unique_attr = 58
+
+
+class Class059(Class058, Class057, Class056):
+    unique_attr = 59
+
+
+class Class060(Class059, Class058, Class057):
+    unique_attr = 60
+
+
+class Class061(Class060, Class059, Class058):
+    unique_attr = 61
+
+
+class Class062(Class061, Class060, Class059):
+    unique_attr = 62
+
+
+class Class063(Class062, Class061, Class060):
+    unique_attr = 63
+
+
+class Class064(Class063, Class062, Class061):
+    unique_attr = 64
+
+
+class Class065(Class064, Class063, Class062):
+    unique_attr = 65
+
+
+class Class066(Class065, Class064, Class063):
+    unique_attr = 66
+
+
+class Class067(Class066, Class065, Class064):
+    unique_attr = 67
+
+
+class Class068(Class067, Class066, Class065):
+    unique_attr = 68
+
+
+class Class069(Class068, Class067, Class066):
+    unique_attr = 69
+
+
+class Class070(Class069, Class068, Class067):
+    unique_attr = 70
+
+
+class Class071(Class070, Class069, Class068):
+    unique_attr = 71
+
+
+class Class072(Class071, Class070, Class069):
+    unique_attr = 72
+
+
+class Class073(Class072, Class071, Class070):
+    unique_attr = 73
+
+
+class Class074(Class073, Class072, Class071):
+    unique_attr = 74
+
+
+class Class075(Class074, Class073, Class072):
+    unique_attr = 75
+
+
+class Class076(Class075, Class074, Class073):
+    unique_attr = 76
+
+
+class Class077(Class076, Class075, Class074):
+    unique_attr = 77
+
+
+class Class078(Class077, Class076, Class075):
+    unique_attr = 78
+
+
+class Class079(Class078, Class077, Class076):
+    unique_attr = 79
+
+
+class Class080(Class079, Class078, Class077):
+    unique_attr = 80
+
+
+class Class081(Class080, Class079, Class078):
+    unique_attr = 81
+
+
+class Class082(Class081, Class080, Class079):
+    unique_attr = 82
+
+
+class Class083(Class082, Class081, Class080):
+    unique_attr = 83
+
+
+class Class084(Class083, Class082, Class081):
+    unique_attr = 84
+
+
+class Class085(Class084, Class083, Class082):
+    unique_attr = 85
+
+
+class Class086(Class085, Class084, Class083):
+    unique_attr = 86
+
+
+class Class087(Class086, Class085, Class084):
+    unique_attr = 87
+
+
+class Class088(Class087, Class086, Class085):
+    unique_attr = 88
+
+
+class Class089(Class088, Class087, Class086):
+    unique_attr = 89
+
+
+class Class090(Class089, Class088, Class087):
+    unique_attr = 90
+
+
+class Class091(Class090, Class089, Class088):
+    unique_attr = 91
+
+
+class Class092(Class091, Class090, Class089):
+    unique_attr = 92
+
+
+class Class093(Class092, Class091, Class090):
+    unique_attr = 93
+
+
+class Class094(Class093, Class092, Class091):
+    unique_attr = 94
+
+
+class Class095(Class094, Class093, Class092):
+    unique_attr = 95
+
+
+class Class096(Class095, Class094, Class093):
+    unique_attr = 96
+
+
+class Class097(Class096, Class095, Class094):
+    unique_attr = 97
+
+
+class Class098(Class097, Class096, Class095):
+    unique_attr = 98
+
+
+class Class099(Class098, Class097, Class096):
+    unique_attr = 99
+
+
+class Class100(Class099, Class098, Class097):
+    unique_attr = 100
+

python/testSrc/com/jetbrains/python/codeInsight/PyClassMROTest.java

@@ -72,16 +72,19 @@ public class PyClassMROTest extends PyTestCase {
     assertMRO(getClass("H"), "E", "F", "B", "G", "C", "D", "A", "object");
   }
 
-  public void testTangledInheritance() throws Exception {
+  public void testTangledInheritance() {
+    final int numClasses = 100;
+
     final List<String> expectedMRO = new ArrayList<String>();
-    for (int i = 29; i >= 1; i--) {
+    for (int i = numClasses - 1; i >= 1; i--) {
       expectedMRO.add(String.format("Class%03d", i));
     }
     expectedMRO.add("object");
+    final PyClass pyClass = getClass(String.format("Class%03d", numClasses));
     final long startTime = System.currentTimeMillis();
-    assertMRO(getClass("Class030"), ArrayUtil.toStringArray(expectedMRO));
+    assertMRO(pyClass, ArrayUtil.toStringArray(expectedMRO));
     final long elapsed = System.currentTimeMillis() - startTime;
-    assertTrue("Calculation of MRO takes too much time: " + elapsed + " ms", elapsed < 5000);
+    assertTrue("Calculation of MRO takes too much time: " + elapsed + " ms", elapsed < 1000);
   }
 
   public void assertMRO(@NotNull PyClass cls, @NotNull String... mro) {