[jsinterp] Actual JS interpreter

youtube_dl/jsinterp2/jsbuilt_ins/jsarray.py

@@ -59,11 +59,18 @@ def _shift(self):
     def _slice(self, start, end=None):
         from .utils import to_js
 
-        length = to_uint32(to_js(len(self.value)))
-        start = to_integer(to_js(start))
-        end = length if end is undefined else to_integer(to_js(end))
+        start = to_js(start)
+        end = to_js(end)
+        length = to_js(len(self.value))
+
+        length = to_uint32(length)
+        start = to_integer(start)
+        end = length if end is undefined else to_integer(end)
+
         start = min(start, length) if start > 0 else max(length + start, 0)
 
+        # TODO add jstest for it
+
         return self.value[start:end]
 
     def _sort(self, cmp):

youtube_dl/jsinterp2/jsinterp.py

@@ -241,9 +241,16 @@ def interpret_expression(self, expr):
 
         elif name is Token.ID:
             # XXX error handling (unknown id)
-            ref = (self.this[expr[1]] if expr[1] in self.this else
-                   self.global_vars[expr[1]])
-
+            id = expr[1]
+            try:
+                ref = (self.this[id] if id in self.this else
+                       self.global_vars[id])
+            except KeyError:
+                try:
+                    ref = Reference(self.extract_object(id))
+                except AttributeError:
+                    ref = Reference(self.extract_function(id))
+
         # literal
         elif name in token_keys:
             ref = Reference(expr[1])