[jsinterp] Fixing types and operators

- Adds `jsbuilt_ins.nan` and `jsbuilt_ins.infinity`
- Adds arithmetic operator overload to
  `jsbuilt_ins.jsnumber.JSNumberPrototype`
- Adds equality operator overload to `jsinterp.Reference`
- Adds better strict equality and typeof operator in `tstream`

youtube_dl/jsinterp2/jsbuilt_ins/__init__.py

@@ -10,6 +10,7 @@ from . import jsnumber
 
 from .base import null, undefined
 from .jsboolean import false, true
+from .jsnumber import infinity, nan
 
 
 def _eval(code):

youtube_dl/jsinterp2/jsbuilt_ins/jsnumber.py

@@ -16,6 +16,34 @@ class JSNumberPrototype(JSObjectPrototype):
             self.value = value
             self.own = {}
 
+    def __add__(self, other):
+        if isinstance(other, JSNumberPrototype):
+            other = other.value
+        return JSNumberPrototype(self.value + other)
+
+    def __sub__(self, other):
+        if isinstance(other, JSNumberPrototype):
+            other = other.value
+        return JSNumberPrototype(self.value - other)
+
+    def __mul__(self, other):
+        if isinstance(other, JSNumberPrototype):
+            other = other.value
+        return JSNumberPrototype(self.value * other)
+
+    def __div__(self, other):
+        if isinstance(other, JSNumberPrototype):
+            other = other.value
+        return JSNumberPrototype(self.value / other)
+
+    def __neg__(self):
+        return JSNumberPrototype(-self.value)
+
+    def __pos__(self):
+        return JSNumberPrototype(+self.value)
+
+    # __invert__?
+
     @staticmethod
     def _constructor(value=None):
         return JSNumber.construct(value)
@@ -53,6 +81,10 @@ class JSNumberPrototype(JSObjectPrototype):
     }
 
 
+nan = JSNumberPrototype(float('nan'))
+infinity = JSNumberPrototype(float('inf'))
+
+
 class JSNumber(JSObject):
     @staticmethod
     def call(value=None):
@@ -68,7 +100,7 @@ class JSNumber(JSObject):
         'prototype': JSNumberPrototype(),
         'MAX_VALUE': 1.7976931348623157 * 10 ** 308,
         'MIN_VALUE': 5 * 10 ** (-324),
-        'NAN': float('nan'),
-        'NEGATIVE_INFINITY': float('-inf'),
-        'POSITIVE_INFINITY': float('inf'),
+        'NAN': nan,
+        'NEGATIVE_INFINITY': infinity * -1,
+        'POSITIVE_INFINITY': infinity,
     }

youtube_dl/jsinterp2/jsinterp.py

@@ -25,10 +25,13 @@ class Context(object):
 
 
 class Reference(object):
-    def __init__(self, value, parent=None):
+    def __init__(self, value, parent_key=None):
         super(Reference, self).__init__()
         self._value = value
-        self._parent = parent
+        if parent_key is not None:
+            self._parent, self._name = parent_key
+        else:
+            self._parent = self._name = None
 
     def getvalue(self, deep=False):
         value = self._value
@@ -46,10 +49,9 @@ class Reference(object):
     def putvalue(self, value):
         if self._parent is None:
             raise ExtractorError('Trying to set a read-only reference')
-        parent, key = self._parent
-        if not hasattr(parent, '__setitem__'):
+        if not hasattr(self._parent, '__setitem__'):
             raise ExtractorError('Unknown reference')
-        parent.__setitem__(key, Reference(value, (parent, key)))
+        self._parent.__setitem__(self._name, Reference(value, (self._parent, self._name)))
         self._value = value
         return value
 
@@ -60,6 +62,14 @@ class Reference(object):
                 str(self._value), parent.__class__.__name__, id(parent), key)
         return '<Reference value: %s, parent: %s>' % (self._value, None)
 
+    def __eq__(self, other):
+        if isinstance(other, Reference):
+            return self._parent is other._parent and self._name == other._name
+        return False
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
 
 class JSInterpreter(object):
     # TODO support json

youtube_dl/jsinterp2/tstream.py

@@ -16,6 +16,35 @@ from .jsgrammar import (
     UNARY_OPERATORS_RE,
     TokenTypes
 )
+from .jsbuilt_ins import false, true, nan
+from .jsbuilt_ins.internals import jstype, undefined_type, null_type, number_type, boolean_type, string_type
+
+
+def convert_to_unary(token_value):
+    return {TokenTypes.ADD: _UNARY_OPERATORS['+'], TokenTypes.SUB: _UNARY_OPERATORS['-']}[token_value[0]]
+
+
+def strict_equal(x, y):
+    from .jsinterp import Reference
+
+    if jstype(x) != jstype(y):
+        return False
+    if jstype(x) in (undefined_type, null_type):
+        return True
+    if jstype(x) is number_type:
+        if x is nan or y is nan:
+            return False
+        if x.value == y.value:
+            return True
+        return False
+    if jstype(x):
+        return x.value == y.value
+    if jstype(x) is boolean_type:
+        return (x is true and y is true) or (x is false and y is false)
+    if isinstance(x, Reference):
+        return isinstance(y, Reference) and x == y
+    return False
+
 
 _PUNCTUATIONS = {
     '{': TokenTypes.COPEN,
@@ -35,8 +64,8 @@ _LOGICAL_OPERATORS = {
     '||': (TokenTypes.OR, lambda cur, right: cur or right)
 }
 _UNARY_OPERATORS = {
-    '+': (TokenTypes.PLUS, lambda cur: cur),
-    '-': (TokenTypes.NEG, lambda cur: cur * -1),
+    '+': (TokenTypes.PLUS, operator.pos),
+    '-': (TokenTypes.NEG, operator.neg),
     '++': (TokenTypes.INC, lambda cur: cur + 1),
     '--': (TokenTypes.DEC, lambda cur: cur - 1),
     '!': (TokenTypes.NOT, operator.not_),
@@ -44,7 +73,7 @@ _UNARY_OPERATORS = {
     # XXX define these operators
     'delete': (TokenTypes.DEL, None),
     'void': (TokenTypes.VOID, None),
-    'typeof': (TokenTypes.TYPE, lambda cur: type(cur))
+    'typeof': (TokenTypes.TYPE, lambda cur: _type_strings[jstype(cur)])
 }
 _RELATIONS = {
     '<': (TokenTypes.LT, operator.lt),
@@ -54,8 +83,8 @@ _RELATIONS = {
     # XXX check python and JavaScript equality difference
     '==': (TokenTypes.EQ, operator.eq),
     '!=': (TokenTypes.NE, operator.ne),
-    '===': (TokenTypes.SEQ, lambda cur, right: cur == right and type(cur) == type(right)),
-    '!==': (TokenTypes.SNE, lambda cur, right: not cur == right or not type(cur) == type(right)),
+    '===': (TokenTypes.SEQ, strict_equal),
+    '!==': (TokenTypes.SNE, lambda cur, right: not strict_equal(cur, right)),
     'in': (TokenTypes.IN, operator.contains),
     'instanceof': (TokenTypes.INSTANCEOF, lambda cur, right: isinstance(cur, right))
 }
@@ -100,9 +129,13 @@ _input_element = re.compile(r'\s*(?:%(comment)s|%(token)s|%(lop)s|%(uop)s|%(aop)
 
 _line_terminator = re.compile(LINETERMINATORSEQ_RE)
 
-
-def convert_to_unary(token_value):
-    return {TokenTypes.ADD: _UNARY_OPERATORS['+'], TokenTypes.SUB: _UNARY_OPERATORS['-']}[token_value[0]]
+_type_strings = {
+    undefined_type: 'undefinied',
+    null_type: 'null',
+    boolean_type: 'boolean',
+    number_type: 'number',
+    string_type: 'string'
+}
 
 
 class Token(object):