Function checkSchema

javascript/selenium-webdriver/project_bidi_schema.mjs:432–536

(schema)

 * @returns {string[]} One message per problem; empty when valid.
 */
export function checkSchema(schema) {
  const errors = []
  const has = (name) => Object.hasOwn(schema.types, name)
  const refsIn = (node) =>
    !node
      ? []
      : node.ref
        ? [node.ref]
        : node.list
          ? refsIn(node.list)
          : node.map
            ? refsIn(node.map)
            : node.union
              ? node.union.flatMap(refsIn)
              : node.record
                ? node.record.flatMap((f) => refsIn(f.type))
                : []
  const hasUnknown = (node) =>
    !node
      ? false
      : node.primitive === 'unknown'
        ? true
        : node.list
          ? hasUnknown(node.list)
          : node.map
            ? hasUnknown(node.map)
            : node.union
              ? node.union.some(hasUnknown)
              : node.record
                ? node.record.some((f) => hasUnknown(f.type))
                : false
  const hasEmptyInlineRecord = (node) =>
    !node
      ? false
      : Array.isArray(node.record)
        ? node.record.length === 0 || node.record.some((f) => hasEmptyInlineRecord(f.type))
        : node.list
          ? hasEmptyInlineRecord(node.list)
          : node.map
            ? hasEmptyInlineRecord(node.map)
            : node.union
              ? node.union.some(hasEmptyInlineRecord)
              : false
  const report = (where, node) => {
    for (const r of refsIn(node)) if (!has(r)) errors.push(`${where}: unresolved type ${r}`)
    if (hasUnknown(node)) errors.push(`${where}: projected to an unknown primitive (unhandled CDDL type)`)
    if (hasEmptyInlineRecord(node)) errors.push(`${where}: projected an empty inline record (dropped type reference)`)
  }

  for (const c of [...schema.commands, ...schema.events]) {
    report(c.method, c.params)
    report(c.method, c.result ?? null)
  }
  // A command/event whose envelope record carries real params must surface them —
  // guards the model builder's gap where an inline `params: {...}` (vs a named ref)
  // was dropped, leaving it parameterless while its type still required them.
  const envelopeParams = commandEnvelopeParams(schema.types)
  for (const c of [...schema.commands, ...schema.events]) {