from unittest import TestCase from unittest.mock import MagicMock from pyjsparser import parse from jasinta import interpret import std as jasinta_std class TestBasicAddition(TestCase): def setUp(self): self.mock_print = MagicMock() jasinta_std.lib["document"]["write"] = self.mock_print def test_interpret(self): s = """var a=3; var b=1; var c=a+b; document.write(c);""" interpret(parse(s)) self.mock_print.assert_called_with(4.0)