fixed PY-3245 Should complain about named param after *args on Python ≤2.5

python/src/com/jetbrains/python/validation/CompatibilityVisitor.java

@@ -430,6 +430,17 @@ public abstract class CompatibilityVisitor extends PyAnnotator {
     super.visitPyCallExpression(node);
     int len = 0;
     StringBuilder message = new StringBuilder(myCommonMessage);
+
+    if (myVersionsToProcess.contains(LanguageLevel.PYTHON24) || myVersionsToProcess.contains(LanguageLevel.PYTHON25)) {
+      boolean hasStar = false;
+      for (PyExpression argument : node.getArguments()) {
+        if (hasStar && argument instanceof PyKeywordArgument) {
+          registerProblem(argument, "Python version < 2.6 doesn't support this syntax. Named parameter cannot appear past *arg or **kwarg.");
+        }
+        if (argument instanceof PyStarArgument) hasStar = true;
+      }
+    }
+
     for (int i = 0; i != myVersionsToProcess.size(); ++i) {
       LanguageLevel languageLevel = myVersionsToProcess.get(i);
       if (!languageLevel.isPy3K()) {

python/testData/inspections/PyCompatibilityInspection/callExpression.py

@@ -6,4 +6,11 @@ class A(B):
 <warning descr="Python version 3.0, 3.1 do not have method reduce">reduce()</warning>
 <warning descr="Python version 2.4 does not have method all">all()</warning>
 
-<warning descr="Python version 3.0, 3.1 do not have method buffer">buffer()</warning>
+<warning descr="Python version 3.0, 3.1 do not have method buffer">buffer()</warning>
+
+def foo(a,b,c):
+  print (a,b,c)
+
+args=['b']
+foo('a', c='c', *args) # OK
+foo('a', *args, <warning descr="Python version < 2.6 doesn't support this syntax. Named parameter cannot appear past *arg or **kwarg.">c='c'</warning>) # Not OK

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

@@ -49,7 +49,13 @@ public class PyArgumentListInspectionTest extends PyTestCase {
   }
   
   public void testPy1268() {
-    doTest();
+    PythonLanguageLevelPusher.setForcedLanguageLevel(myFixture.getProject(), LanguageLevel.PYTHON30);
+    try {
+      doTest();
+    }
+    finally {
+      PythonLanguageLevelPusher.setForcedLanguageLevel(myFixture.getProject(), null);
+    }
   }
   
   public void testInstanceMethodAsLambda() {