parser.test.js

const Tokenizer = require('./tokenizer')
const Parser = require('./parser')
const token = Tokenizer.tokenEnum

const parseString = str => {
  const tokenizer = new Tokenizer(str)
  const tokens = tokenizer.scanTokens()
  const parser = new Parser(tokens)
  return parser
}

describe('Expression Parsing', () => {
  test('Parses primary characters correctly', () => {
    const primaries = [
      // Numbers
      `3`,
      `321`,
      `.3`,
      `.321`,
      `321.123`,

      // Strings
      `""`,
      `"hello"`,
      `"
        <strong>
          Independent Woman
        </strong>
      "`,
      // True
      `true`,
      // False
      `false`,
      // Nil
      `nil`
    ]
    for (let primary of primaries) {
      expect(parseString(primary).expression()).toMatchSnapshot()
    }
  })

  test('Parses unaries correctly', () => {
    const unaries = [`-3`, `!3`]
    for (const u of unaries) {
      expect(parseString(u).expression()).toMatchSnapshot()
    }
  })

  test('Parses multiplication correctly', () => {
    const mult = [`3 * 1`, `-2 * 2`, `-3 * -3`, `3 / 1`, `-2 / 2`, `-3 / -3`]
    for (const u of mult) {
      expect(parseString(u).expression()).toMatchSnapshot()
    }
  })

  test('Parses addition correctly', () => {
    const add = [`3 + 1`, `-2 + 2`, `-3 + -3`, `3 - 1`, `-2 - 2`, `-3 - -3`]
    for (const u of add) {
      expect(parseString(u).expression()).toMatchSnapshot()
    }
  })

  test('Parses comparison correctly', () => {
    const comp = [`3 > 1`, `2 < 2`, `3 <= 3`, `3 >= 1`]
    for (const u of comp) {
      expect(parseString(u).expression()).toMatchSnapshot()
    }
  })

  test('Parses equality correctly', () => {
    const equals = [`3 == 3`, `3 != 2`, `3 != -3`, `-3 != -3`, `!true != true`, `!true == !true`]
    for (const u of equals) {
      expect(parseString(u).expression()).toMatchSnapshot()
    }
  })
})