shift-interpreter/test/evaluation/binary-expressions.test.ts

Shift-interpreter is an experimental JavaScript meta-interpreter useful for reverse engineering and analysis. One notable difference from other projects is that shift-interpreter retains state over an entire script but can be fed expressions and statement

import { assertResult, compare } from '../util';

const operators = [
  '==',
  '!=',
  '===',
  '!==',
  '<',
  '<=',
  '>',
  '>=',
  '<<',
  '>>',
  '>>>',
  '+',
  '-',
  '*',
  '/',
  '%',
  '**',
  ',',
  '&&',
  ',',
  '^',
  '&',
];
// const specialOps = ['in' , 'instanceof'];
describe('BinaryExpressions', () => {
  it('should evaluate operators the same as the host environment', () => {
    const sample = [2, 120, 1981, '2', 'hi', NaN, true, false, 1 / 0];
    const results = operators.flatMap(op =>
      sample.flatMap(l => sample.map(r => compare(`${JSON.stringify(l)} ${op} ${JSON.stringify(r)}`))),
    );
    results.forEach(result => assertResult(result));
  });
  it('should retain shortcircuit behavior', () => {
    assertResult(compare(`typeof x == 'string' && nonexistant()`));
  });
});