Python: Modernise the py/not-named-self query.

RasmusWL · RasmusWL · commit a81bf720f537 · 2019-09-26T13:25:14.000+02:00
diff --git a/python/ql/src/Functions/NonSelf.ql b/python/ql/src/Functions/NonSelf.ql
@@ -16,39 +16,37 @@
 import python
 import semmle.python.libraries.Zope
 
-predicate first_arg_self(Function f) {
-    f.getArgName(0) = "self"
+predicate is_type_method(FunctionValue fv) {
+    exists(ClassValue c | c.declaredAttribute(_) = fv and c.getASuperType() = ClassValue::type())
 }
 
-predicate is_type_method(FunctionObject f) {
-    exists(ClassObject c | c.lookupAttribute(_) = f and c.getASuperType() = theTypeType())
-}
-
-predicate used_in_defining_scope(FunctionObject f) {
-    exists(Call c | 
-        c.getScope() = f.getFunction().getScope() and
-        c.getFunc().refersTo(f)
+predicate used_in_defining_scope(FunctionValue fv) {
+    exists(Call c |
+        c.getScope() = fv.getScope().getScope() and c.getFunc().pointsTo(fv)
     )
 }
 
-from Function f, PyFunctionObject func, string message
+from Function f, FunctionValue fv, string message
 where
-exists(ClassObject cls, string name |
-    cls.declaredAttribute(name) = func and cls.isNewStyle() and
+exists(ClassValue cls, string name |
+    cls.declaredAttribute(name) = fv and cls.isNewStyle() and
     not name = "__new__" and
     not name = "__metaclass__" and
     /* declared in scope */
-    f.getScope() = cls.getPyClass()
+    f.getScope() = cls.getScope()
 ) and
-not first_arg_self(f) and not is_type_method(func) and
-func.getFunction() = f and not f.getName() = "lambda" and
-not used_in_defining_scope(func) and
+not f.getArgName(0) = "self" and
+not is_type_method(fv) and
+fv.getScope() = f and
+not f.getName() = "lambda" and
+not used_in_defining_scope(fv) and
 (
   if exists(f.getArgName(0)) then
       message = "Normal methods should have 'self', rather than '" + f.getArgName(0) + "', as their first parameter."
   else
-      message = "Normal methods should have at least one parameter (the first of which should be 'self')." and not f.hasVarArg()
+      message = "Normal methods should have at least one parameter (the first of which should be 'self')." and
+      not f.hasVarArg()
 ) and
-not func instanceof ZopeInterfaceMethod
+not fv instanceof ZopeInterfaceMethodValue
 
 select f, message
diff --git a/python/ql/src/semmle/python/libraries/Zope.qll b/python/ql/src/semmle/python/libraries/Zope.qll
@@ -2,8 +2,10 @@
 
 import python
 
+private import semmle.python.pointsto.PointsTo
+
 /** A method that to a sub-class of `zope.interface.Interface` */
-class ZopeInterfaceMethod extends PyFunctionObject {
+deprecated class ZopeInterfaceMethod extends PyFunctionObject {
 
     /** Holds if this method belongs to a class that sub-classes `zope.interface.Interface` */
     ZopeInterfaceMethod() {
@@ -26,3 +28,20 @@ class ZopeInterfaceMethod extends PyFunctionObject {
     }
 
 }
+
+/** A method that belongs to a sub-class of `zope.interface.Interface` */
+class ZopeInterfaceMethodValue extends PythonFunctionValue {
+
+    /** Holds if this method belongs to a class that sub-classes `zope.interface.Interface` */
+    ZopeInterfaceMethodValue() {
+        exists(Value interface, ClassValue owner |
+            interface = Module::named("zope.interface").attr("Interface") and
+            owner.declaredAttribute(_) = this and
+            // `zope.interface.Interface` will be recognized as a Value by the pointsTo analysis,
+            // because it is the result of instantiating a "meta" class. getASuperType only returns
+            // ClassValues, so we do this little trick to make things work
+            Types::getBase(owner.getASuperType(), _) = interface
+        )
+    }
+
+}
diff --git a/python/ql/test/library-tests/types/functions/Zope.expected b/python/ql/test/library-tests/types/functions/Zope.expected
@@ -1 +1 @@
-| Function yes |
+| Function Z.yes |
diff --git a/python/ql/test/library-tests/types/functions/Zope.ql b/python/ql/test/library-tests/types/functions/Zope.ql
@@ -2,5 +2,5 @@
 import python
 import semmle.python.libraries.Zope
 
-from ZopeInterfaceMethod f
+from ZopeInterfaceMethodValue f
 select f.toString()
