Index: node_modules/node-gyp/lib/create-config-gypi.js
===================================================================
--- node_modules/node-gyp/lib/create-config-gypi.js	(revision 81bc7da776d8cda42939ef4ab350c88d13b4941f)
+++ node_modules/node-gyp/lib/create-config-gypi.js	(revision 81bc7da776d8cda42939ef4ab350c88d13b4941f)
@@ -0,0 +1,146 @@
+'use strict'
+
+const fs = require('graceful-fs')
+const log = require('npmlog')
+const path = require('path')
+
+function parseConfigGypi (config) {
+  // translated from tools/js2c.py of Node.js
+  // 1. string comments
+  config = config.replace(/#.*/g, '')
+  // 2. join multiline strings
+  config = config.replace(/'$\s+'/mg, '')
+  // 3. normalize string literals from ' into "
+  config = config.replace(/'/g, '"')
+  return JSON.parse(config)
+}
+
+async function getBaseConfigGypi ({ gyp, nodeDir }) {
+  // try reading $nodeDir/include/node/config.gypi first when:
+  // 1. --dist-url or --nodedir is specified
+  // 2. and --force-process-config is not specified
+  const shouldReadConfigGypi = (gyp.opts.nodedir || gyp.opts['dist-url']) && !gyp.opts['force-process-config']
+  if (shouldReadConfigGypi && nodeDir) {
+    try {
+      const baseConfigGypiPath = path.resolve(nodeDir, 'include/node/config.gypi')
+      const baseConfigGypi = await fs.promises.readFile(baseConfigGypiPath)
+      return parseConfigGypi(baseConfigGypi.toString())
+    } catch (err) {
+      log.warn('read config.gypi', err.message)
+    }
+  }
+
+  // fallback to process.config if it is invalid
+  return JSON.parse(JSON.stringify(process.config))
+}
+
+async function getCurrentConfigGypi ({ gyp, nodeDir, vsInfo }) {
+  const config = await getBaseConfigGypi({ gyp, nodeDir })
+  if (!config.target_defaults) {
+    config.target_defaults = {}
+  }
+  if (!config.variables) {
+    config.variables = {}
+  }
+
+  const defaults = config.target_defaults
+  const variables = config.variables
+
+  // don't inherit the "defaults" from the base config.gypi.
+  // doing so could cause problems in cases where the `node` executable was
+  // compiled on a different machine (with different lib/include paths) than
+  // the machine where the addon is being built to
+  defaults.cflags = []
+  defaults.defines = []
+  defaults.include_dirs = []
+  defaults.libraries = []
+
+  // set the default_configuration prop
+  if ('debug' in gyp.opts) {
+    defaults.default_configuration = gyp.opts.debug ? 'Debug' : 'Release'
+  }
+
+  if (!defaults.default_configuration) {
+    defaults.default_configuration = 'Release'
+  }
+
+  // set the target_arch variable
+  variables.target_arch = gyp.opts.arch || process.arch || 'ia32'
+  if (variables.target_arch === 'arm64') {
+    defaults.msvs_configuration_platform = 'ARM64'
+    defaults.xcode_configuration_platform = 'arm64'
+  }
+
+  // set the node development directory
+  variables.nodedir = nodeDir
+
+  // disable -T "thin" static archives by default
+  variables.standalone_static_library = gyp.opts.thin ? 0 : 1
+
+  if (process.platform === 'win32') {
+    defaults.msbuild_toolset = vsInfo.toolset
+    if (vsInfo.sdk) {
+      defaults.msvs_windows_target_platform_version = vsInfo.sdk
+    }
+    if (variables.target_arch === 'arm64') {
+      if (vsInfo.versionMajor > 15 ||
+          (vsInfo.versionMajor === 15 && vsInfo.versionMajor >= 9)) {
+        defaults.msvs_enable_marmasm = 1
+      } else {
+        log.warn('Compiling ARM64 assembly is only available in\n' +
+          'Visual Studio 2017 version 15.9 and above')
+      }
+    }
+    variables.msbuild_path = vsInfo.msBuild
+  }
+
+  // loop through the rest of the opts and add the unknown ones as variables.
+  // this allows for module-specific configure flags like:
+  //
+  //   $ node-gyp configure --shared-libxml2
+  Object.keys(gyp.opts).forEach(function (opt) {
+    if (opt === 'argv') {
+      return
+    }
+    if (opt in gyp.configDefs) {
+      return
+    }
+    variables[opt.replace(/-/g, '_')] = gyp.opts[opt]
+  })
+
+  return config
+}
+
+async function createConfigGypi ({ gyp, buildDir, nodeDir, vsInfo }) {
+  const configFilename = 'config.gypi'
+  const configPath = path.resolve(buildDir, configFilename)
+
+  log.verbose('build/' + configFilename, 'creating config file')
+
+  const config = await getCurrentConfigGypi({ gyp, nodeDir, vsInfo })
+
+  // ensures that any boolean values in config.gypi get stringified
+  function boolsToString (k, v) {
+    if (typeof v === 'boolean') {
+      return String(v)
+    }
+    return v
+  }
+
+  log.silly('build/' + configFilename, config)
+
+  // now write out the config.gypi file to the build/ dir
+  const prefix = '# Do not edit. File was generated by node-gyp\'s "configure" step'
+
+  const json = JSON.stringify(config, boolsToString, 2)
+  log.verbose('build/' + configFilename, 'writing out config file: %s', configPath)
+  await fs.promises.writeFile(configPath, [prefix, json, ''].join('\n'))
+
+  return configPath
+}
+
+module.exports = createConfigGypi
+module.exports.test = {
+  parseConfigGypi: parseConfigGypi,
+  getCurrentConfigGypi: getCurrentConfigGypi
+}
