PY-21220 Handle moved classes that contain both __init__ and __new__

I changed behavior of PyClassImpl#NameFinder processor, so that it
always tries to find an element with the first of the names passed to
its constructor. In particular, #findInitOrNew() returns __init__
unless there was only __new__ defined in the class. Otherwise its
behavior contradicts with the method's javadoc.

python/testSrc/com/jetbrains/python/PyResolveTest.java

@@ -30,6 +30,7 @@ import com.jetbrains.python.psi.impl.PyBuiltinCache;
 import com.jetbrains.python.psi.impl.PyPsiUtils;
 import com.jetbrains.python.psi.impl.PythonLanguageLevelPusher;
 import com.jetbrains.python.psi.resolve.ImportedResolveResult;
+import com.jetbrains.python.psi.types.TypeEvalContext;
 
 public class PyResolveTest extends PyResolveTestCase {
   @Override
@@ -70,6 +71,22 @@ public class PyResolveTest extends PyResolveTestCase {
     assertEquals(PyNames.INIT, ((PyFunction)target).getName());
   }
 
+  public void testInitOrNewReturnsInitWhenNewIsFirst() {
+    doTestInitOrNewReturnsInit();
+  }
+  
+  public void testInitOrNewReturnsInitWhenNewIsLast() {
+    doTestInitOrNewReturnsInit();
+  }
+
+  private void doTestInitOrNewReturnsInit() {
+    myFixture.configureByFile("resolve/" + getTestName(false) + ".py");
+    final PyClass pyClass = PsiTreeUtil.findChildOfType(myFixture.getFile(), PyClass.class);
+    assertNotNull(pyClass);
+    final PyFunction init = pyClass.findInitOrNew(false, TypeEvalContext.userInitiated(myFixture.getProject(), myFixture.getFile()));
+    assertEquals(PyNames.INIT, init.getName());
+  }
+
   public void testToConstructorInherited() {
     ResolveResult[] targets = multiResolve();
     assertEquals(2, targets.length); // to class, to init

python/testSrc/com/jetbrains/python/refactoring/PyMoveTest.java

@@ -376,6 +376,11 @@ public class PyMoveTest extends PyTestCase {
     doMoveSymbolTest("FOO", "b.py");
   }
 
+  // PY-21220
+  public void testReferenceToClassWithNewInMovedSymbol() {
+    doMoveSymbolTest("fnToMove", "toFile.py");
+  }
+
   private void doMoveFileTest(String fileName, String toDirName) {
     Project project = myFixture.getProject();
     PsiManager manager = PsiManager.getInstance(project);