src/language-js/parser-flow.js/parse
function parse(text, parsers, opts) {
  // Inline the require to avoid loading all the JS if we don't use it
  const flowParser = require("flow-parser");

  const ast = flowParser.parse(text, {
    enums: true,
    esproposal_decorators: true,
    esproposal_class_instance_fields: true,
    esproposal_class_static_fields: true,
    esproposal_export_star_as: true,
    esproposal_optional_chaining: true,
    esproposal_nullish_coalescing: true,
  });

  if (ast.errors.length > 0) {
    const { loc } = ast.errors[0];
    throw createError(ast.errors[0].message, {
      start: { line: loc.start.line, column: loc.start.column + 1 },
      end: { line: loc.end.line, column: loc.end.column + 1 },
    });
  }

  return postprocess(ast, { ...opts, originalText: text });
}