def eval(self, expression, context=None):
if context is None:
context = js.ExecutionContext({})
if not isinstance(context, js.ExecutionContext):
context = js.ExecutionContext(context)
expression_ast = self.parser.parse(expression)
return js.get_value(expression_ast.eval(context))
def eval(self, stmt, context=None):
if context is None:
context = js.ExecutionContext({})
if not isinstance(context, js.ExecutionContext):
context = js.ExecutionContext(context)
stmt_ast = self.parser.parse(stmt)
return js.get_value(stmt_ast.eval(context))
def test_closure(self):
program = """var fibgen = function () {
var a = 0, b = 1;
return function () {
var old = a;
a = b;
b = b + old;
return old;
};
};
var fib = fibgen();
var f1 = fib();
var f2 = fib();
fib(); fib(); fib(); fib();
var f7 = fib();
fib(); fib(); fib(); fib();
var fib2 = fibgen();
fib2(); fib2(); fib2(); fib2();
var f5 = fib2();
fib(); // f12
"""
context = js.ExecutionContext({})
self.assertEqual(self.eval(program, context),
js.Completion(js.NORMAL, 89, js.EMPTY))
self.assertEqual(context['f1'], 0)
self.assertEqual(context['f2'], 1)
self.assertEqual(context['f5'], 3)
self.assertEqual(context['f7'], 8)
def test_object_set_property(self):
context = js.ExecutionContext(
{'x': js.Object({
'cheese': 7,
'ham': 3
})})
self.assertEqual(self.eval('x["cheese"] = 4', context), 4)
self.assertEqual(context['x']['cheese'], 4)
def test_object_set_new_property(self):
context = js.ExecutionContext(
{'x': js.Object({
'cheese': 7,
'ham': 3
})})
self.assertEqual(self.eval('x["spam"] = 2', context), 2)
self.assertEqual(context['x']['spam'], 2)
def test_shadowing(self):
program = """var x = 1;
var shadow = function () {
var x = 3; x += 1; return x;
};
shadow();"""
context = js.ExecutionContext({})
self.assertEqual(self.eval(program, context), js.Completion(js.NORMAL, 4, js.EMPTY))
self.assertEqual(context['x'], 1)
def test_console_object(self):
program = """var i = 0;
while (i < 10) {
console.log(i);
i++;
}
"""
out = StringIO()
context = js.ExecutionContext({'console': js.Console(out=out)})
self.assertEqual(self.eval(program, context), js.Completion(js.NORMAL, 9, js.EMPTY))
self.assertEqual(out.getvalue(), "0.0\n1.0\n2.0\n3.0\n4.0\n5.0\n6.0\n7.0\n8.0\n9.0\n")
def test_break_statement(self):
stmt = """while (x < 10) {
++x;
if (x % 3 == 0)
break;
++y;
}"""
context = js.ExecutionContext({'x': 0, 'y': 0})
self.assertEqual(self.eval(stmt, context), js.Completion(js.NORMAL, 2, js.EMPTY))
self.assertEqual(context['x'], 3)
self.assertEqual(context['y'], 2)
def test_continue_statement(self):
stmt = """while (x < 10) {
++x;
if (x % 2 == 0)
continue;
++y;
}"""
context = js.ExecutionContext({'x': 0, 'y': 0})
self.assertEqual(self.eval(stmt, context), js.Completion(js.NORMAL, 5, js.EMPTY))
self.assertEqual(context['x'], 10)
self.assertEqual(context['y'], 5)
def eval(self, context):
result_value = js.EMPTY
cntx = js.ExecutionContext(dict(), parent=context)
while True:
condition_value = js.get_value(self.condition.eval(cntx))
if not condition_value:
return js.Completion(js.NORMAL, result_value, js.EMPTY)
stmt = self.statement.eval(cntx)
if stmt.value is not js.EMPTY:
result_value = stmt.value
if stmt.type is js.BREAK:
return js.Completion(js.NORMAL, result_value, js.EMPTY)
elif js.is_abrupt(stmt) and stmt.type is not js.CONTINUE:
return stmt
def test_postfix_op(self):
context = js.ExecutionContext({'x': 3})
self.assertEqual(self.eval('x++', context), 3)
self.assertEqual(context['x'], 4)
self.assertEqual(self.eval('x--', context), 4)
self.assertEqual(context['x'], 3)
def test_prefix_op(self):
context = js.ExecutionContext({'x': 3})
self.assertEqual(self.eval('++x', context), 4)
self.assertEqual(context['x'], 4)
self.assertEqual(self.eval('--x', context), 3)
self.assertEqual(context['x'], 3)
def test_while_statement(self):
context = js.ExecutionContext({'x': 3})
self.assertEqual(self.eval('while (x < 5) ++x;', context),
js.Completion(js.NORMAL, 5, js.EMPTY))
self.assertEqual(context['x'], 5)
def test_do_while_statement(self):
context = js.ExecutionContext({'x': 3})
self.assertEqual(self.eval('do ++x; while (x < 3);', context),
js.Completion(js.NORMAL, 4, js.EMPTY))
self.assertEqual(context['x'], 4)
def test_variable_declaration_list(self):
context = js.ExecutionContext({})
self.assertEqual(self.eval('var x = 7, y = 5;', context),
js.EMPTY_COMPLETION)
self.assertEqual(context['x'], 7)
self.assertEqual(context['y'], 5)
def test_compound_assignment(self):
context = js.ExecutionContext({'x': 15})
self.assertEqual(self.eval('x /= 5 - 2', context), 5)
self.assertEqual(context['x'], 5)
def test_array_set_index(self):
context = js.ExecutionContext({'x': js.Array([9, 10, 'ala ma kota'])})
self.assertEqual(self.eval('x[2] = 11', context), 11)
self.assertEqual(context['x'], js.Array([9, 10, 11]))
