feat(vanilla): add testing infrastructure and tests (NK-wjnczv)

1 files changed, 1003 insertions, 0 deletions

diff --git a/vanilla/node_modules/undici/lib/web/webidl/index.js b/vanilla/node_modules/undici/lib/web/webidl/index.js
new file mode 100644
index 0000000..c783432
--- /dev/null
+++ b/vanilla/node_modules/undici/lib/web/webidl/index.js
@@ -0,0 +1,1003 @@
+'use strict'
+
+const assert = require('node:assert')
+const { types, inspect } = require('node:util')
+const { runtimeFeatures } = require('../../util/runtime-features')
+
+const UNDEFINED = 1
+const BOOLEAN = 2
+const STRING = 3
+const SYMBOL = 4
+const NUMBER = 5
+const BIGINT = 6
+const NULL = 7
+const OBJECT = 8 // function and object
+
+const FunctionPrototypeSymbolHasInstance = Function.call.bind(Function.prototype[Symbol.hasInstance])
+
+/** @type {import('../../../types/webidl').Webidl} */
+const webidl = {
+  converters: {},
+  util: {},
+  errors: {},
+  is: {}
+}
+
+/**
+ * @description Instantiate an error.
+ *
+ * @param {Object} opts
+ * @param {string} opts.header
+ * @param {string} opts.message
+ * @returns {TypeError}
+ */
+webidl.errors.exception = function (message) {
+  return new TypeError(`${message.header}: ${message.message}`)
+}
+
+/**
+ * @description Instantiate an error when conversion from one type to another has failed.
+ *
+ * @param {Object} opts
+ * @param {string} opts.prefix
+ * @param {string} opts.argument
+ * @param {string[]} opts.types
+ * @returns {TypeError}
+ */
+webidl.errors.conversionFailed = function (opts) {
+  const plural = opts.types.length === 1 ? '' : ' one of'
+  const message =
+    `${opts.argument} could not be converted to` +
+    `${plural}: ${opts.types.join(', ')}.`
+
+  return webidl.errors.exception({
+    header: opts.prefix,
+    message
+  })
+}
+
+/**
+ * @description Instantiate an error when an invalid argument is provided
+ *
+ * @param {Object} context
+ * @param {string} context.prefix
+ * @param {string} context.value
+ * @param {string} context.type
+ * @returns {TypeError}
+ */
+webidl.errors.invalidArgument = function (context) {
+  return webidl.errors.exception({
+    header: context.prefix,
+    message: `"${context.value}" is an invalid ${context.type}.`
+  })
+}
+
+// https://webidl.spec.whatwg.org/#implements
+webidl.brandCheck = function (V, I) {
+  if (!FunctionPrototypeSymbolHasInstance(I, V)) {
+    const err = new TypeError('Illegal invocation')
+    err.code = 'ERR_INVALID_THIS' // node compat.
+    throw err
+  }
+}
+
+webidl.brandCheckMultiple = function (List) {
+  const prototypes = List.map((c) => webidl.util.MakeTypeAssertion(c))
+
+  return (V) => {
+    if (prototypes.every(typeCheck => !typeCheck(V))) {
+      const err = new TypeError('Illegal invocation')
+      err.code = 'ERR_INVALID_THIS' // node compat.
+      throw err
+    }
+  }
+}
+
+webidl.argumentLengthCheck = function ({ length }, min, ctx) {
+  if (length < min) {
+    throw webidl.errors.exception({
+      message: `${min} argument${min !== 1 ? 's' : ''} required, ` +
+               `but${length ? ' only' : ''} ${length} found.`,
+      header: ctx
+    })
+  }
+}
+
+webidl.illegalConstructor = function () {
+  throw webidl.errors.exception({
+    header: 'TypeError',
+    message: 'Illegal constructor'
+  })
+}
+
+webidl.util.MakeTypeAssertion = function (I) {
+  return (O) => FunctionPrototypeSymbolHasInstance(I, O)
+}
+
+// https://tc39.es/ecma262/#sec-ecmascript-data-types-and-values
+webidl.util.Type = function (V) {
+  switch (typeof V) {
+    case 'undefined': return UNDEFINED
+    case 'boolean': return BOOLEAN
+    case 'string': return STRING
+    case 'symbol': return SYMBOL
+    case 'number': return NUMBER
+    case 'bigint': return BIGINT
+    case 'function':
+    case 'object': {
+      if (V === null) {
+        return NULL
+      }
+
+      return OBJECT
+    }
+  }
+}
+
+webidl.util.Types = {
+  UNDEFINED,
+  BOOLEAN,
+  STRING,
+  SYMBOL,
+  NUMBER,
+  BIGINT,
+  NULL,
+  OBJECT
+}
+
+webidl.util.TypeValueToString = function (o) {
+  switch (webidl.util.Type(o)) {
+    case UNDEFINED: return 'Undefined'
+    case BOOLEAN: return 'Boolean'
+    case STRING: return 'String'
+    case SYMBOL: return 'Symbol'
+    case NUMBER: return 'Number'
+    case BIGINT: return 'BigInt'
+    case NULL: return 'Null'
+    case OBJECT: return 'Object'
+  }
+}
+
+webidl.util.markAsUncloneable = runtimeFeatures.has('markAsUncloneable')
+  ? require('node:worker_threads').markAsUncloneable
+  : () => {}
+
+// https://webidl.spec.whatwg.org/#abstract-opdef-converttoint
+webidl.util.ConvertToInt = function (V, bitLength, signedness, flags) {
+  let upperBound
+  let lowerBound
+
+  // 1. If bitLength is 64, then:
+  if (bitLength === 64) {
+    // 1. Let upperBound be 2^53 − 1.
+    upperBound = Math.pow(2, 53) - 1
+
+    // 2. If signedness is "unsigned", then let lowerBound be 0.
+    if (signedness === 'unsigned') {
+      lowerBound = 0
+    } else {
+      // 3. Otherwise let lowerBound be −2^53 + 1.
+      lowerBound = Math.pow(-2, 53) + 1
+    }
+  } else if (signedness === 'unsigned') {
+    // 2. Otherwise, if signedness is "unsigned", then:
+
+    // 1. Let lowerBound be 0.
+    lowerBound = 0
+
+    // 2. Let upperBound be 2^bitLength − 1.
+    upperBound = Math.pow(2, bitLength) - 1
+  } else {
+    // 3. Otherwise:
+
+    // 1. Let lowerBound be -2^bitLength − 1.
+    lowerBound = Math.pow(-2, bitLength) - 1
+
+    // 2. Let upperBound be 2^bitLength − 1 − 1.
+    upperBound = Math.pow(2, bitLength - 1) - 1
+  }
+
+  // 4. Let x be ? ToNumber(V).
+  let x = Number(V)
+
+  // 5. If x is −0, then set x to +0.
+  if (x === 0) {
+    x = 0
+  }
+
+  // 6. If the conversion is to an IDL type associated
+  //    with the [EnforceRange] extended attribute, then:
+  if (webidl.util.HasFlag(flags, webidl.attributes.EnforceRange)) {
+    // 1. If x is NaN, +∞, or −∞, then throw a TypeError.
+    if (
+      Number.isNaN(x) ||
+      x === Number.POSITIVE_INFINITY ||
+      x === Number.NEGATIVE_INFINITY
+    ) {
+      throw webidl.errors.exception({
+        header: 'Integer conversion',
+        message: `Could not convert ${webidl.util.Stringify(V)} to an integer.`
+      })
+    }
+
+    // 2. Set x to IntegerPart(x).
+    x = webidl.util.IntegerPart(x)
+
+    // 3. If x < lowerBound or x > upperBound, then
+    //    throw a TypeError.
+    if (x < lowerBound || x > upperBound) {
+      throw webidl.errors.exception({
+        header: 'Integer conversion',
+        message: `Value must be between ${lowerBound}-${upperBound}, got ${x}.`
+      })
+    }
+
+    // 4. Return x.
+    return x
+  }
+
+  // 7. If x is not NaN and the conversion is to an IDL
+  //    type associated with the [Clamp] extended
+  //    attribute, then:
+  if (!Number.isNaN(x) && webidl.util.HasFlag(flags, webidl.attributes.Clamp)) {
+    // 1. Set x to min(max(x, lowerBound), upperBound).
+    x = Math.min(Math.max(x, lowerBound), upperBound)
+
+    // 2. Round x to the nearest integer, choosing the
+    //    even integer if it lies halfway between two,
+    //    and choosing +0 rather than −0.
+    if (Math.floor(x) % 2 === 0) {
+      x = Math.floor(x)
+    } else {
+      x = Math.ceil(x)
+    }
+
+    // 3. Return x.
+    return x
+  }
+
+  // 8. If x is NaN, +0, +∞, or −∞, then return +0.
+  if (
+    Number.isNaN(x) ||
+    (x === 0 && Object.is(0, x)) ||
+    x === Number.POSITIVE_INFINITY ||
+    x === Number.NEGATIVE_INFINITY
+  ) {
+    return 0
+  }
+
+  // 9. Set x to IntegerPart(x).
+  x = webidl.util.IntegerPart(x)
+
+  // 10. Set x to x modulo 2^bitLength.
+  x = x % Math.pow(2, bitLength)
+
+  // 11. If signedness is "signed" and x ≥ 2^bitLength − 1,
+  //    then return x − 2^bitLength.
+  if (signedness === 'signed' && x >= Math.pow(2, bitLength) - 1) {
+    return x - Math.pow(2, bitLength)
+  }
+
+  // 12. Otherwise, return x.
+  return x
+}
+
+// https://webidl.spec.whatwg.org/#abstract-opdef-integerpart
+webidl.util.IntegerPart = function (n) {
+  // 1. Let r be floor(abs(n)).
+  const r = Math.floor(Math.abs(n))
+
+  // 2. If n < 0, then return -1 × r.
+  if (n < 0) {
+    return -1 * r
+  }
+
+  // 3. Otherwise, return r.
+  return r
+}
+
+webidl.util.Stringify = function (V) {
+  const type = webidl.util.Type(V)
+
+  switch (type) {
+    case SYMBOL:
+      return `Symbol(${V.description})`
+    case OBJECT:
+      return inspect(V)
+    case STRING:
+      return `"${V}"`
+    case BIGINT:
+      return `${V}n`
+    default:
+      return `${V}`
+  }
+}
+
+webidl.util.IsResizableArrayBuffer = function (V) {
+  if (types.isArrayBuffer(V)) {
+    return V.resizable
+  }
+
+  if (types.isSharedArrayBuffer(V)) {
+    return V.growable
+  }
+
+  throw webidl.errors.exception({
+    header: 'IsResizableArrayBuffer',
+    message: `"${webidl.util.Stringify(V)}" is not an array buffer.`
+  })
+}
+
+webidl.util.HasFlag = function (flags, attributes) {
+  return typeof flags === 'number' && (flags & attributes) === attributes
+}
+
+// https://webidl.spec.whatwg.org/#es-sequence
+webidl.sequenceConverter = function (converter) {
+  return (V, prefix, argument, Iterable) => {
+    // 1. If Type(V) is not Object, throw a TypeError.
+    if (webidl.util.Type(V) !== OBJECT) {
+      throw webidl.errors.exception({
+        header: prefix,
+        message: `${argument} (${webidl.util.Stringify(V)}) is not iterable.`
+      })
+    }
+
+    // 2. Let method be ? GetMethod(V, @@iterator).
+    /** @type {Generator} */
+    const method = typeof Iterable === 'function' ? Iterable() : V?.[Symbol.iterator]?.()
+    const seq = []
+    let index = 0
+
+    // 3. If method is undefined, throw a TypeError.
+    if (
+      method === undefined ||
+      typeof method.next !== 'function'
+    ) {
+      throw webidl.errors.exception({
+        header: prefix,
+        message: `${argument} is not iterable.`
+      })
+    }
+
+    // https://webidl.spec.whatwg.org/#create-sequence-from-iterable
+    while (true) {
+      const { done, value } = method.next()
+
+      if (done) {
+        break
+      }
+
+      seq.push(converter(value, prefix, `${argument}[${index++}]`))
+    }
+
+    return seq
+  }
+}
+
+// https://webidl.spec.whatwg.org/#es-to-record
+webidl.recordConverter = function (keyConverter, valueConverter) {
+  return (O, prefix, argument) => {
+    // 1. If Type(O) is not Object, throw a TypeError.
+    if (webidl.util.Type(O) !== OBJECT) {
+      throw webidl.errors.exception({
+        header: prefix,
+        message: `${argument} ("${webidl.util.TypeValueToString(O)}") is not an Object.`
+      })
+    }
+
+    // 2. Let result be a new empty instance of record<K, V>.
+    const result = {}
+
+    if (!types.isProxy(O)) {
+      // 1. Let desc be ? O.[[GetOwnProperty]](key).
+      const keys = [...Object.getOwnPropertyNames(O), ...Object.getOwnPropertySymbols(O)]
+
+      for (const key of keys) {
+        const keyName = webidl.util.Stringify(key)
+
+        // 1. Let typedKey be key converted to an IDL value of type K.
+        const typedKey = keyConverter(key, prefix, `Key ${keyName} in ${argument}`)
+
+        // 2. Let value be ? Get(O, key).
+        // 3. Let typedValue be value converted to an IDL value of type V.
+        const typedValue = valueConverter(O[key], prefix, `${argument}[${keyName}]`)
+
+        // 4. Set result[typedKey] to typedValue.
+        result[typedKey] = typedValue
+      }
+
+      // 5. Return result.
+      return result
+    }
+
+    // 3. Let keys be ? O.[[OwnPropertyKeys]]().
+    const keys = Reflect.ownKeys(O)
+
+    // 4. For each key of keys.
+    for (const key of keys) {
+      // 1. Let desc be ? O.[[GetOwnProperty]](key).
+      const desc = Reflect.getOwnPropertyDescriptor(O, key)
+
+      // 2. If desc is not undefined and desc.[[Enumerable]] is true:
+      if (desc?.enumerable) {
+        // 1. Let typedKey be key converted to an IDL value of type K.
+        const typedKey = keyConverter(key, prefix, argument)
+
+        // 2. Let value be ? Get(O, key).
+        // 3. Let typedValue be value converted to an IDL value of type V.
+        const typedValue = valueConverter(O[key], prefix, argument)
+
+        // 4. Set result[typedKey] to typedValue.
+        result[typedKey] = typedValue
+      }
+    }
+
+    // 5. Return result.
+    return result
+  }
+}
+
+webidl.interfaceConverter = function (TypeCheck, name) {
+  return (V, prefix, argument) => {
+    if (!TypeCheck(V)) {
+      throw webidl.errors.exception({
+        header: prefix,
+        message: `Expected ${argument} ("${webidl.util.Stringify(V)}") to be an instance of ${name}.`
+      })
+    }
+
+    return V
+  }
+}
+
+webidl.dictionaryConverter = function (converters) {
+  return (dictionary, prefix, argument) => {
+    const dict = {}
+
+    if (dictionary != null && webidl.util.Type(dictionary) !== OBJECT) {
+      throw webidl.errors.exception({
+        header: prefix,
+        message: `Expected ${dictionary} to be one of: Null, Undefined, Object.`
+      })
+    }
+
+    for (const options of converters) {
+      const { key, defaultValue, required, converter } = options
+
+      if (required === true) {
+        if (dictionary == null || !Object.hasOwn(dictionary, key)) {
+          throw webidl.errors.exception({
+            header: prefix,
+            message: `Missing required key "${key}".`
+          })
+        }
+      }
+
+      let value = dictionary?.[key]
+      const hasDefault = defaultValue !== undefined
+
+      // Only use defaultValue if value is undefined and
+      // a defaultValue options was provided.
+      if (hasDefault && value === undefined) {
+        value = defaultValue()
+      }
+
+      // A key can be optional and have no default value.
+      // When this happens, do not perform a conversion,
+      // and do not assign the key a value.
+      if (required || hasDefault || value !== undefined) {
+        value = converter(value, prefix, `${argument}.${key}`)
+
+        if (
+          options.allowedValues &&
+          !options.allowedValues.includes(value)
+        ) {
+          throw webidl.errors.exception({
+            header: prefix,
+            message: `${value} is not an accepted type. Expected one of ${options.allowedValues.join(', ')}.`
+          })
+        }
+
+        dict[key] = value
+      }
+    }
+
+    return dict
+  }
+}
+
+webidl.nullableConverter = function (converter) {
+  return (V, prefix, argument) => {
+    if (V === null) {
+      return V
+    }
+
+    return converter(V, prefix, argument)
+  }
+}
+
+/**
+ * @param {*} value
+ * @returns {boolean}
+ */
+webidl.is.USVString = function (value) {
+  return (
+    typeof value === 'string' &&
+    value.isWellFormed()
+  )
+}
+
+webidl.is.ReadableStream = webidl.util.MakeTypeAssertion(ReadableStream)
+webidl.is.Blob = webidl.util.MakeTypeAssertion(Blob)
+webidl.is.URLSearchParams = webidl.util.MakeTypeAssertion(URLSearchParams)
+webidl.is.File = webidl.util.MakeTypeAssertion(File)
+webidl.is.URL = webidl.util.MakeTypeAssertion(URL)
+webidl.is.AbortSignal = webidl.util.MakeTypeAssertion(AbortSignal)
+webidl.is.MessagePort = webidl.util.MakeTypeAssertion(MessagePort)
+
+webidl.is.BufferSource = function (V) {
+  return types.isArrayBuffer(V) || (
+    ArrayBuffer.isView(V) &&
+    types.isArrayBuffer(V.buffer)
+  )
+}
+
+// https://webidl.spec.whatwg.org/#dfn-get-buffer-source-copy
+webidl.util.getCopyOfBytesHeldByBufferSource = function (bufferSource) {
+  // 1. Let jsBufferSource be the result of converting bufferSource to a JavaScript value.
+  const jsBufferSource = bufferSource
+
+  // 2. Let jsArrayBuffer be jsBufferSource.
+  let jsArrayBuffer = jsBufferSource
+
+  // 3. Let offset be 0.
+  let offset = 0
+
+  // 4. Let length be 0.
+  let length = 0
+
+  // 5. If jsBufferSource has a [[ViewedArrayBuffer]] internal slot, then:
+  if (types.isTypedArray(jsBufferSource) || types.isDataView(jsBufferSource)) {
+    // 5.1. Set jsArrayBuffer to jsBufferSource.[[ViewedArrayBuffer]].
+    jsArrayBuffer = jsBufferSource.buffer
+
+    // 5.2. Set offset to jsBufferSource.[[ByteOffset]].
+    offset = jsBufferSource.byteOffset
+
+    // 5.3. Set length to jsBufferSource.[[ByteLength]].
+    length = jsBufferSource.byteLength
+  } else {
+    // 6. Otherwise:
+
+    // 6.1. Assert: jsBufferSource is an ArrayBuffer or SharedArrayBuffer object.
+    assert(types.isAnyArrayBuffer(jsBufferSource))
+
+    // 6.2. Set length to jsBufferSource.[[ArrayBufferByteLength]].
+    length = jsBufferSource.byteLength
+  }
+
+  // 7. If IsDetachedBuffer(jsArrayBuffer) is true, then return the empty byte sequence.
+  if (jsArrayBuffer.detached) {
+    return new Uint8Array(0)
+  }
+
+  // 8. Let bytes be a new byte sequence of length equal to length.
+  const bytes = new Uint8Array(length)
+
+  // 9. For i in the range offset to offset + length − 1, inclusive,
+  //    set bytes[i − offset] to GetValueFromBuffer(jsArrayBuffer, i, Uint8, true, Unordered).
+  const view = new Uint8Array(jsArrayBuffer, offset, length)
+  bytes.set(view)
+
+  // 10. Return bytes.
+  return bytes
+}
+
+// https://webidl.spec.whatwg.org/#es-DOMString
+webidl.converters.DOMString = function (V, prefix, argument, flags) {
+  // 1. If V is null and the conversion is to an IDL type
+  //    associated with the [LegacyNullToEmptyString]
+  //    extended attribute, then return the DOMString value
+  //    that represents the empty string.
+  if (V === null && webidl.util.HasFlag(flags, webidl.attributes.LegacyNullToEmptyString)) {
+    return ''
+  }
+
+  // 2. Let x be ? ToString(V).
+  if (typeof V === 'symbol') {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} is a symbol, which cannot be converted to a DOMString.`
+    })
+  }
+
+  // 3. Return the IDL DOMString value that represents the
+  //    same sequence of code units as the one the
+  //    ECMAScript String value x represents.
+  return String(V)
+}
+
+// https://webidl.spec.whatwg.org/#es-ByteString
+webidl.converters.ByteString = function (V, prefix, argument) {
+  // 1. Let x be ? ToString(V).
+  if (typeof V === 'symbol') {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} is a symbol, which cannot be converted to a ByteString.`
+    })
+  }
+
+  const x = String(V)
+
+  // 2. If the value of any element of x is greater than
+  //    255, then throw a TypeError.
+  for (let index = 0; index < x.length; index++) {
+    if (x.charCodeAt(index) > 255) {
+      throw new TypeError(
+        'Cannot convert argument to a ByteString because the character at ' +
+        `index ${index} has a value of ${x.charCodeAt(index)} which is greater than 255.`
+      )
+    }
+  }
+
+  // 3. Return an IDL ByteString value whose length is the
+  //    length of x, and where the value of each element is
+  //    the value of the corresponding element of x.
+  return x
+}
+
+/**
+ * @param {unknown} value
+ * @returns {string}
+ * @see https://webidl.spec.whatwg.org/#es-USVString
+ */
+webidl.converters.USVString = function (value) {
+  // TODO: rewrite this so we can control the errors thrown
+  if (typeof value === 'string') {
+    return value.toWellFormed()
+  }
+  return `${value}`.toWellFormed()
+}
+
+// https://webidl.spec.whatwg.org/#es-boolean
+webidl.converters.boolean = function (V) {
+  // 1. Let x be the result of computing ToBoolean(V).
+  // https://262.ecma-international.org/10.0/index.html#table-10
+  const x = Boolean(V)
+
+  // 2. Return the IDL boolean value that is the one that represents
+  //    the same truth value as the ECMAScript Boolean value x.
+  return x
+}
+
+// https://webidl.spec.whatwg.org/#es-any
+webidl.converters.any = function (V) {
+  return V
+}
+
+// https://webidl.spec.whatwg.org/#es-long-long
+webidl.converters['long long'] = function (V, prefix, argument) {
+  // 1. Let x be ? ConvertToInt(V, 64, "signed").
+  const x = webidl.util.ConvertToInt(V, 64, 'signed', 0, prefix, argument)
+
+  // 2. Return the IDL long long value that represents
+  //    the same numeric value as x.
+  return x
+}
+
+// https://webidl.spec.whatwg.org/#es-unsigned-long-long
+webidl.converters['unsigned long long'] = function (V, prefix, argument) {
+  // 1. Let x be ? ConvertToInt(V, 64, "unsigned").
+  const x = webidl.util.ConvertToInt(V, 64, 'unsigned', 0, prefix, argument)
+
+  // 2. Return the IDL unsigned long long value that
+  //    represents the same numeric value as x.
+  return x
+}
+
+// https://webidl.spec.whatwg.org/#es-unsigned-long
+webidl.converters['unsigned long'] = function (V, prefix, argument) {
+  // 1. Let x be ? ConvertToInt(V, 32, "unsigned").
+  const x = webidl.util.ConvertToInt(V, 32, 'unsigned', 0, prefix, argument)
+
+  // 2. Return the IDL unsigned long value that
+  //    represents the same numeric value as x.
+  return x
+}
+
+// https://webidl.spec.whatwg.org/#es-unsigned-short
+webidl.converters['unsigned short'] = function (V, prefix, argument, flags) {
+  // 1. Let x be ? ConvertToInt(V, 16, "unsigned").
+  const x = webidl.util.ConvertToInt(V, 16, 'unsigned', flags, prefix, argument)
+
+  // 2. Return the IDL unsigned short value that represents
+  //    the same numeric value as x.
+  return x
+}
+
+// https://webidl.spec.whatwg.org/#idl-ArrayBuffer
+webidl.converters.ArrayBuffer = function (V, prefix, argument, flags) {
+  // 1. If V is not an Object, or V does not have an
+  //    [[ArrayBufferData]] internal slot, then throw a
+  //    TypeError.
+  // 2. If IsSharedArrayBuffer(V) is true, then throw a
+  //    TypeError.
+  // see: https://tc39.es/ecma262/#sec-properties-of-the-arraybuffer-instances
+  if (
+    webidl.util.Type(V) !== OBJECT ||
+    !types.isArrayBuffer(V)
+  ) {
+    throw webidl.errors.conversionFailed({
+      prefix,
+      argument: `${argument} ("${webidl.util.Stringify(V)}")`,
+      types: ['ArrayBuffer']
+    })
+  }
+
+  // 3. If the conversion is not to an IDL type associated
+  //    with the [AllowResizable] extended attribute, and
+  //    IsResizableArrayBuffer(V) is true, then throw a
+  //    TypeError.
+  if (!webidl.util.HasFlag(flags, webidl.attributes.AllowResizable) && webidl.util.IsResizableArrayBuffer(V)) {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} cannot be a resizable ArrayBuffer.`
+    })
+  }
+
+  // 4. Return the IDL ArrayBuffer value that is a
+  //    reference to the same object as V.
+  return V
+}
+
+// https://webidl.spec.whatwg.org/#idl-SharedArrayBuffer
+webidl.converters.SharedArrayBuffer = function (V, prefix, argument, flags) {
+  // 1. If V is not an Object, or V does not have an
+  //    [[ArrayBufferData]] internal slot, then throw a
+  //    TypeError.
+  // 2. If IsSharedArrayBuffer(V) is false, then throw a
+  //    TypeError.
+  // see: https://tc39.es/ecma262/#sec-properties-of-the-sharedarraybuffer-instances
+  if (
+    webidl.util.Type(V) !== OBJECT ||
+    !types.isSharedArrayBuffer(V)
+  ) {
+    throw webidl.errors.conversionFailed({
+      prefix,
+      argument: `${argument} ("${webidl.util.Stringify(V)}")`,
+      types: ['SharedArrayBuffer']
+    })
+  }
+
+  // 3. If the conversion is not to an IDL type associated
+  //    with the [AllowResizable] extended attribute, and
+  //    IsResizableArrayBuffer(V) is true, then throw a
+  //    TypeError.
+  if (!webidl.util.HasFlag(flags, webidl.attributes.AllowResizable) && webidl.util.IsResizableArrayBuffer(V)) {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} cannot be a resizable SharedArrayBuffer.`
+    })
+  }
+
+  // 4. Return the IDL SharedArrayBuffer value that is a
+  //    reference to the same object as V.
+  return V
+}
+
+// https://webidl.spec.whatwg.org/#dfn-typed-array-type
+webidl.converters.TypedArray = function (V, T, prefix, argument, flags) {
+  // 1. Let T be the IDL type V is being converted to.
+
+  // 2. If Type(V) is not Object, or V does not have a
+  //    [[TypedArrayName]] internal slot with a value
+  //    equal to T’s name, then throw a TypeError.
+  if (
+    webidl.util.Type(V) !== OBJECT ||
+    !types.isTypedArray(V) ||
+    V.constructor.name !== T.name
+  ) {
+    throw webidl.errors.conversionFailed({
+      prefix,
+      argument: `${argument} ("${webidl.util.Stringify(V)}")`,
+      types: [T.name]
+    })
+  }
+
+  // 3. If the conversion is not to an IDL type associated
+  //    with the [AllowShared] extended attribute, and
+  //    IsSharedArrayBuffer(V.[[ViewedArrayBuffer]]) is
+  //    true, then throw a TypeError.
+  if (!webidl.util.HasFlag(flags, webidl.attributes.AllowShared) && types.isSharedArrayBuffer(V.buffer)) {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} cannot be a view on a shared array buffer.`
+    })
+  }
+
+  // 4. If the conversion is not to an IDL type associated
+  //    with the [AllowResizable] extended attribute, and
+  //    IsResizableArrayBuffer(V.[[ViewedArrayBuffer]]) is
+  //    true, then throw a TypeError.
+  if (!webidl.util.HasFlag(flags, webidl.attributes.AllowResizable) && webidl.util.IsResizableArrayBuffer(V.buffer)) {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} cannot be a view on a resizable array buffer.`
+    })
+  }
+
+  // 5. Return the IDL value of type T that is a reference
+  //    to the same object as V.
+  return V
+}
+
+// https://webidl.spec.whatwg.org/#idl-DataView
+webidl.converters.DataView = function (V, prefix, argument, flags) {
+  // 1. If Type(V) is not Object, or V does not have a
+  //    [[DataView]] internal slot, then throw a TypeError.
+  if (webidl.util.Type(V) !== OBJECT || !types.isDataView(V)) {
+    throw webidl.errors.conversionFailed({
+      prefix,
+      argument: `${argument} ("${webidl.util.Stringify(V)}")`,
+      types: ['DataView']
+    })
+  }
+
+  // 2. If the conversion is not to an IDL type associated
+  //    with the [AllowShared] extended attribute, and
+  //    IsSharedArrayBuffer(V.[[ViewedArrayBuffer]]) is true,
+  //    then throw a TypeError.
+  if (!webidl.util.HasFlag(flags, webidl.attributes.AllowShared) && types.isSharedArrayBuffer(V.buffer)) {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} cannot be a view on a shared array buffer.`
+    })
+  }
+
+  // 3. If the conversion is not to an IDL type associated
+  //    with the [AllowResizable] extended attribute, and
+  //    IsResizableArrayBuffer(V.[[ViewedArrayBuffer]]) is
+  //    true, then throw a TypeError.
+  if (!webidl.util.HasFlag(flags, webidl.attributes.AllowResizable) && webidl.util.IsResizableArrayBuffer(V.buffer)) {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} cannot be a view on a resizable array buffer.`
+    })
+  }
+
+  // 4. Return the IDL DataView value that is a reference
+  //    to the same object as V.
+  return V
+}
+
+// https://webidl.spec.whatwg.org/#ArrayBufferView
+webidl.converters.ArrayBufferView = function (V, prefix, argument, flags) {
+  if (
+    webidl.util.Type(V) !== OBJECT ||
+    !types.isArrayBufferView(V)
+  ) {
+    throw webidl.errors.conversionFailed({
+      prefix,
+      argument: `${argument} ("${webidl.util.Stringify(V)}")`,
+      types: ['ArrayBufferView']
+    })
+  }
+
+  if (!webidl.util.HasFlag(flags, webidl.attributes.AllowShared) && types.isSharedArrayBuffer(V.buffer)) {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} cannot be a view on a shared array buffer.`
+    })
+  }
+
+  if (!webidl.util.HasFlag(flags, webidl.attributes.AllowResizable) && webidl.util.IsResizableArrayBuffer(V.buffer)) {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} cannot be a view on a resizable array buffer.`
+    })
+  }
+
+  return V
+}
+
+// https://webidl.spec.whatwg.org/#BufferSource
+webidl.converters.BufferSource = function (V, prefix, argument, flags) {
+  if (types.isArrayBuffer(V)) {
+    return webidl.converters.ArrayBuffer(V, prefix, argument, flags)
+  }
+
+  if (types.isArrayBufferView(V)) {
+    flags &= ~webidl.attributes.AllowShared
+
+    return webidl.converters.ArrayBufferView(V, prefix, argument, flags)
+  }
+
+  // Make this explicit for easier debugging
+  if (types.isSharedArrayBuffer(V)) {
+    throw webidl.errors.exception({
+      header: prefix,
+      message: `${argument} cannot be a SharedArrayBuffer.`
+    })
+  }
+
+  throw webidl.errors.conversionFailed({
+    prefix,
+    argument: `${argument} ("${webidl.util.Stringify(V)}")`,
+    types: ['ArrayBuffer', 'ArrayBufferView']
+  })
+}
+
+// https://webidl.spec.whatwg.org/#AllowSharedBufferSource
+webidl.converters.AllowSharedBufferSource = function (V, prefix, argument, flags) {
+  if (types.isArrayBuffer(V)) {
+    return webidl.converters.ArrayBuffer(V, prefix, argument, flags)
+  }
+
+  if (types.isSharedArrayBuffer(V)) {
+    return webidl.converters.SharedArrayBuffer(V, prefix, argument, flags)
+  }
+
+  if (types.isArrayBufferView(V)) {
+    flags |= webidl.attributes.AllowShared
+    return webidl.converters.ArrayBufferView(V, prefix, argument, flags)
+  }
+
+  throw webidl.errors.conversionFailed({
+    prefix,
+    argument: `${argument} ("${webidl.util.Stringify(V)}")`,
+    types: ['ArrayBuffer', 'SharedArrayBuffer', 'ArrayBufferView']
+  })
+}
+
+webidl.converters['sequence<ByteString>'] = webidl.sequenceConverter(
+  webidl.converters.ByteString
+)
+
+webidl.converters['sequence<sequence<ByteString>>'] = webidl.sequenceConverter(
+  webidl.converters['sequence<ByteString>']
+)
+
+webidl.converters['record<ByteString, ByteString>'] = webidl.recordConverter(
+  webidl.converters.ByteString,
+  webidl.converters.ByteString
+)
+
+webidl.converters.Blob = webidl.interfaceConverter(webidl.is.Blob, 'Blob')
+
+webidl.converters.AbortSignal = webidl.interfaceConverter(
+  webidl.is.AbortSignal,
+  'AbortSignal'
+)
+
+/**
+ * [LegacyTreatNonObjectAsNull]
+ * callback EventHandlerNonNull = any (Event event);
+ * typedef EventHandlerNonNull? EventHandler;
+ * @param {*} V
+ */
+webidl.converters.EventHandlerNonNull = function (V) {
+  if (webidl.util.Type(V) !== OBJECT) {
+    return null
+  }
+
+  // [I]f the value is not an object, it will be converted to null, and if the value is not callable,
+  // it will be converted to a callback function value that does nothing when called.
+  if (typeof V === 'function') {
+    return V
+  }
+
+  return () => {}
+}
+
+webidl.attributes = {
+  Clamp: 1 << 0,
+  EnforceRange: 1 << 1,
+  AllowShared: 1 << 2,
+  AllowResizable: 1 << 3,
+  LegacyNullToEmptyString: 1 << 4
+}
+
+module.exports = {
+  webidl
+}