Add a staticmethod case to ^P test.

python/testData/paramInfo/Staticmethod.py

@@ -0,0 +1,6 @@
+class A(object):
+  @staticmethod
+  def foo(a, b):
+    return a,b
+
+A().foo(<arg1>1, <arg2>2)

python/testSrc/com/jetbrains/python/PyParameterInfoTest.java

@@ -350,7 +350,13 @@ public class PyParameterInfoTest extends LightMarkedTestCase {
   }
 
 
-  // TODO: add method tests with decorators when a mock SDK is available
+  public void testStaticmethod() throws Exception {
+    Map<String, PsiElement> marks = loadTest();
+    assertEquals("Test data sanity", marks.size(), 2);
+
+    feignCtrlP(marks.get("<arg1>").getTextOffset()).check("a,b", new String[]{"a,"});
+    feignCtrlP(marks.get("<arg2>").getTextOffset()).check("a,b", new String[]{"b"});
+  }
 
   /**
    * Imitates pressing of Ctrl+P; fails if results are not as expected.