Function regExpFeatures

scripts/js-api-tests.js:7468–7505

({ esbuild })

  },

  async regExpFeatures({ esbuild }) {
    const check = async (target, input, expected) =>
      assert.strictEqual((await esbuild.transform(input, { target })).code, expected)

    await Promise.all([
      // RegExpStickyAndUnicodeFlags
      check('es6', `x1 = /./y`, `x1 = /./y;\n`),
      check('es6', `x2 = /./u`, `x2 = /./u;\n`),
      check('es5', `x3 = /./y`, `x3 = new RegExp(".", "y");\n`),
      check('es5', `x4 = /./u`, `x4 = new RegExp(".", "u");\n`),

      // RegExpDotAllFlag
      check('es2018', `x1 = /a.b/s`, `x1 = /a.b/s;\n`),
      check('es2017', `x2 = /a.b/s`, `x2 = new RegExp("a.b", "s");\n`),

      // RegExpLookbehindAssertions
      check('es2018', `x1 = /(?<=x)/`, `x1 = /(?<=x)/;\n`),
      check('es2018', `x2 = /(?<!x)/`, `x2 = /(?<!x)/;\n`),
      check('es2017', `x3 = /(?<=x)/`, `x3 = new RegExp("(?<=x)");\n`),
      check('es2017', `x4 = /(?<!x)/`, `x4 = new RegExp("(?<!x)");\n`),

      // RegExpNamedCaptureGroups
      check('es2018', `x1 = /(?<a>b)/`, `x1 = /(?<a>b)/;\n`),
      check('es2017', `x2 = /(?<a>b)/`, `x2 = new RegExp("(?<a>b)");\n`),

      // RegExpUnicodePropertyEscapes
      check('es2018', `x1 = /\\p{Emoji}/u`, `x1 = /\\p{Emoji}/u;\n`),
      check('es2017', `x2 = /\\p{Emoji}/u`, `x2 = new RegExp("\\\\p{Emoji}", "u");\n`),

      // RegExpMatchIndices
      check('es2022', `x1 = /y/d`, `x1 = /y/d;\n`),
      check('es2021', `x2 = /y/d`, `x2 = new RegExp("y", "d");\n`),

      // RegExpSetNotation
      check('es2024', `x1 = /[\\p{White_Space}&&\\p{ASCII}]/v`, `x1 = /[\\p{White_Space}&&\\p{ASCII}]/v;\n`),
      check('es2022', `x2 = /[\\p{White_Space}&&\\p{ASCII}]/v`, `x2 = new RegExp("[\\\\p{White_Space}&&\\\\p{ASCII}]", "v");\n`),
    ])
  },

  // Future syntax
  nonIdArrayRest: ({ esbuild }) => futureSyntax(esbuild, 'let [...[x]] = y', 'es2015', 'es2016'),