diff --git a/lib/configure.js b/lib/configure.js
index 8ccfc3fad5..8d59e33497 100644
--- a/lib/configure.js
+++ b/lib/configure.js
@@ -9,8 +9,8 @@ const win = process.platform === 'win32'
 const findNodeDirectory = require('./find-node-directory')
 const createConfigGypi = require('./create-config-gypi')
 const { format: msgFormat } = require('util')
-const findPython = require('./find-python')
-const findVisualStudio = win ? require('./find-visualstudio') : null
+const { findPython } = require('./find-python')
+const { findVisualStudio } = win ? require('./find-visualstudio') : {}
 
 async function configure (gyp, argv) {
   const buildDir = path.resolve('build')
diff --git a/lib/find-python.js b/lib/find-python.js
index f01d1dd454..615da57bb8 100644
--- a/lib/find-python.js
+++ b/lib/find-python.js
@@ -2,10 +2,15 @@
 
 const log = require('./log')
 const semver = require('semver')
-const { _extend: extend } = require('util') // eslint-disable-line n/no-deprecated-api
 const { execFile } = require('./util')
 const win = process.platform === 'win32'
 
+function getOsUserInfo () {
+  try {
+    return require('os').userInfo().username
+  } catch {}
+}
+
 const systemDrive = process.env.SystemDrive || 'C:'
 const username = process.env.USERNAME || process.env.USER || getOsUserInfo()
 const localAppData = process.env.LOCALAPPDATA || `${systemDrive}\\${username}\\AppData\\Local`
@@ -32,40 +37,36 @@ for (const majorMinor of ['311', '310', '39', '38']) {
   }
 }
 
-function getOsUserInfo () {
-  try {
-    return require('os').userInfo().username
-  } catch (e) {}
-}
-
-function PythonFinder (configPython) {
-  this.configPython = configPython
-  this.errorLog = []
-}
+class PythonFinder {
+  static findPython = (...args) => new PythonFinder(...args).findPython()
 
-PythonFinder.prototype = {
-  log: log.withPrefix('find Python'),
-  argsExecutable: ['-c', 'import sys; print(sys.executable);'],
-  argsVersion: ['-c', 'import sys; print("%s.%s.%s" % sys.version_info[:3]);'],
-  semverRange: '>=3.6.0',
+  log = log.withPrefix('find Python')
+  argsExecutable = ['-c', 'import sys; print(sys.executable);']
+  argsVersion = ['-c', 'import sys; print("%s.%s.%s" % sys.version_info[:3]);']
+  semverRange = '>=3.6.0'
 
   // These can be overridden for testing:
-  execFile,
-  env: process.env,
-  win,
-  pyLauncher: 'py.exe',
-  winDefaultLocations: winDefaultLocationsArray,
+  execFile = execFile
+  env = process.env
+  win = win
+  pyLauncher = 'py.exe'
+  winDefaultLocations = winDefaultLocationsArray
+
+  constructor (configPython) {
+    this.configPython = configPython
+    this.errorLog = []
+  }
 
   // Logs a message at verbose level, but also saves it to be displayed later
   // at error level if an error occurs. This should help diagnose the problem.
-  addLog: function addLog (message) {
+  addLog (message) {
     this.log.verbose(message)
     this.errorLog.push(message)
-  },
+  }
 
   // Find Python by trying a sequence of possibilities.
   // Ignore errors, keep trying until Python is found.
-  findPython: async function findPython () {
+  async findPython () {
     const SKIP = 0
     const FAIL = 1
     const toCheck = (() => {
@@ -161,12 +162,12 @@ PythonFinder.prototype = {
     }
 
     return this.fail()
-  },
+  }
 
   // Check if command is a valid Python to use.
   // Will exit the Python finder on success.
   // If on Windows, run in a CMD shell to support BAT/CMD launchers.
-  checkCommand: async function checkCommand (command) {
+  async checkCommand (command) {
     let exec = command
     let args = this.argsExecutable
     let shell = false
@@ -190,7 +191,7 @@ PythonFinder.prototype = {
       this.addLog(`- "${command}" is not in PATH or produced an error`)
       throw err
     }
-  },
+  }
 
   // Check if the py launcher can find a valid Python to use.
   // Will exit the Python finder on success.
@@ -202,7 +203,7 @@ PythonFinder.prototype = {
   // the first command line argument. Since "py.exe -3" would be an invalid
   // executable for "execFile", we have to use the launcher to figure out
   // where the actual "python.exe" executable is located.
-  checkPyLauncher: async function checkPyLauncher () {
+  async checkPyLauncher () {
     this.log.verbose(`- executing "${this.pyLauncher}" to get Python 3 executable path`)
     // Possible outcomes: same as checkCommand
     try {
@@ -213,11 +214,11 @@ PythonFinder.prototype = {
       this.addLog(`- "${this.pyLauncher}" is not in PATH or produced an error`)
       throw err
     }
-  },
+  }
 
   // Check if a Python executable is the correct version to use.
   // Will exit the Python finder on success.
-  checkExecPath: async function checkExecPath (execPath) {
+  async checkExecPath (execPath) {
     this.log.verbose(`- executing "${execPath}" to get version`)
     // Possible outcomes:
     // - Error: executable can not be run (likely meaning the command wasn't
@@ -249,11 +250,11 @@ PythonFinder.prototype = {
       this.addLog(`- "${execPath}" could not be run`)
       throw err
     }
-  },
+  }
 
   // Run an executable or shell command, trimming the output.
-  run: async function run (exec, args, shell) {
-    const env = extend({}, this.env)
+  async run (exec, args, shell) {
+    const env = Object.assign({}, this.env)
     env.TERM = 'dumb'
     const opts = { env, shell }
 
@@ -270,14 +271,14 @@ PythonFinder.prototype = {
       this.log.silly('execFile: threw:\n%s', err.stack)
       throw err
     }
-  },
+  }
 
-  succeed: function succeed (execPath, version) {
+  succeed (execPath, version) {
     this.log.info(`using Python version ${version} found at "${execPath}"`)
     return execPath
-  },
+  }
 
-  fail: function fail () {
+  fail () {
     const errorLog = this.errorLog.join('\n')
 
     const pathExample = this.win
@@ -306,10 +307,4 @@ PythonFinder.prototype = {
   }
 }
 
-const findPython = async (configPython) => new PythonFinder(configPython).findPython()
-
-module.exports = findPython
-module.exports.test = {
-  PythonFinder,
-  findPython
-}
+module.exports = PythonFinder
diff --git a/lib/find-visualstudio.js b/lib/find-visualstudio.js
index 7df976a2db..b57770259a 100644
--- a/lib/find-visualstudio.js
+++ b/lib/find-visualstudio.js
@@ -5,26 +5,28 @@ const { existsSync } = require('fs')
 const { win32: path } = require('path')
 const { regSearchKeys, execFile } = require('./util')
 
-function VisualStudioFinder (nodeSemver, configMsvsVersion) {
-  this.nodeSemver = nodeSemver
-  this.configMsvsVersion = configMsvsVersion
-  this.errorLog = []
-  this.validVersions = []
-}
+class VisualStudioFinder {
+  static findVisualStudio = (...args) => new VisualStudioFinder(...args).findVisualStudio()
+
+  log = log.withPrefix('find VS')
 
-VisualStudioFinder.prototype = {
-  log: log.withPrefix('find VS'),
+  regSearchKeys = regSearchKeys
 
-  regSearchKeys,
+  constructor (nodeSemver, configMsvsVersion) {
+    this.nodeSemver = nodeSemver
+    this.configMsvsVersion = configMsvsVersion
+    this.errorLog = []
+    this.validVersions = []
+  }
 
   // Logs a message at verbose level, but also saves it to be displayed later
   // at error level if an error occurs. This should help diagnose the problem.
-  addLog: function addLog (message) {
+  addLog (message) {
     this.log.verbose(message)
     this.errorLog.push(message)
-  },
+  }
 
-  findVisualStudio: async function findVisualStudio () {
+  async findVisualStudio () {
     this.configVersionYear = null
     this.configPath = null
     if (this.configMsvsVersion) {
@@ -65,16 +67,16 @@ VisualStudioFinder.prototype = {
     }
 
     return this.fail()
-  },
+  }
 
-  succeed: function succeed (info) {
+  succeed (info) {
     this.log.info(`using VS${info.versionYear} (${info.version}) found at:` +
                   `\n"${info.path}"` +
                   '\nrun with --verbose for detailed information')
     return info
-  },
+  }
 
-  fail: function fail () {
+  fail () {
     if (this.configMsvsVersion && this.envVcInstallDir) {
       this.errorLog.push(
         'msvs_version does not match this VS Command Prompt or the',
@@ -109,11 +111,11 @@ VisualStudioFinder.prototype = {
 
     this.log.error(`\n${errorLog}\n\n${infoLog}\n`)
     throw new Error('Could not find any Visual Studio installation to use')
-  },
+  }
 
   // Invoke the PowerShell script to get information about Visual Studio 2017
   // or newer installations
-  findVisualStudio2017OrNewer: async function findVisualStudio2017OrNewer () {
+  async findVisualStudio2017OrNewer () {
     const ps = path.join(process.env.SystemRoot, 'System32',
       'WindowsPowerShell', 'v1.0', 'powershell.exe')
     const csFile = path.join(__dirname, 'Find-VisualStudio.cs')
@@ -128,11 +130,11 @@ VisualStudioFinder.prototype = {
     this.log.silly('Running', ps, psArgs)
     const [err, stdout, stderr] = await execFile(ps, psArgs, { encoding: 'utf8' })
     return this.parseData(err, stdout, stderr)
-  },
+  }
 
   // Parse the output of the PowerShell script and look for an installation
   // of Visual Studio 2017 or newer to use
-  parseData: function parseData (err, stdout, stderr) {
+  parseData (err, stdout, stderr) {
     this.log.silly('PS stderr = %j', stderr)
 
     const failPowershell = () => {
@@ -220,10 +222,10 @@ VisualStudioFinder.prototype = {
     this.addLog(
       'could not find a version of Visual Studio 2017 or newer to use')
     return null
-  },
+  }
 
   // Helper - process version information
-  getVersionInfo: function getVersionInfo (info) {
+  getVersionInfo (info) {
     const match = /^(\d+)\.(\d+)\..*/.exec(info.version)
     if (!match) {
       this.log.silly('- failed to parse version:', info.version)
@@ -249,14 +251,14 @@ VisualStudioFinder.prototype = {
     }
     this.log.silly('- unsupported version:', ret.versionMajor)
     return {}
-  },
+  }
 
-  msBuildPathExists: function msBuildPathExists (path) {
+  msBuildPathExists (path) {
     return existsSync(path)
-  },
+  }
 
   // Helper - process MSBuild information
-  getMSBuild: function getMSBuild (info, versionYear) {
+  getMSBuild (info, versionYear) {
     const pkg = 'Microsoft.VisualStudio.VC.MSBuild.Base'
     const msbuildPath = path.join(info.path, 'MSBuild', 'Current', 'Bin', 'MSBuild.exe')
     const msbuildPathArm64 = path.join(info.path, 'MSBuild', 'Current', 'Bin', 'arm64', 'MSBuild.exe')
@@ -280,10 +282,10 @@ VisualStudioFinder.prototype = {
       return msbuildPath
     }
     return null
-  },
+  }
 
   // Helper - process toolset information
-  getToolset: function getToolset (info, versionYear) {
+  getToolset (info, versionYear) {
     const pkg = 'Microsoft.VisualStudio.Component.VC.Tools.x86.x64'
     const express = 'Microsoft.VisualStudio.WDExpress'
 
@@ -304,10 +306,10 @@ VisualStudioFinder.prototype = {
     }
     this.log.silly('- invalid versionYear:', versionYear)
     return null
-  },
+  }
 
   // Helper - process Windows SDK information
-  getSDK: function getSDK (info) {
+  getSDK (info) {
     const win8SDK = 'Microsoft.VisualStudio.Component.Windows81SDK'
     const win10SDKPrefix = 'Microsoft.VisualStudio.Component.Windows10SDK.'
     const win11SDKPrefix = 'Microsoft.VisualStudio.Component.Windows11SDK.'
@@ -339,10 +341,10 @@ VisualStudioFinder.prototype = {
       return '8.1'
     }
     return null
-  },
+  }
 
   // Find an installation of Visual Studio 2015 to use
-  findVisualStudio2015: async function findVisualStudio2015 () {
+  async findVisualStudio2015 () {
     if (this.nodeSemver.major >= 19) {
       this.addLog(
         'not looking for VS2015 as it is only supported up to Node.js 18')
@@ -355,10 +357,10 @@ VisualStudioFinder.prototype = {
       versionYear: 2015,
       toolset: 'v140'
     })
-  },
+  }
 
   // Find an installation of Visual Studio 2013 to use
-  findVisualStudio2013: async function findVisualStudio2013 () {
+  async findVisualStudio2013 () {
     if (this.nodeSemver.major >= 9) {
       this.addLog(
         'not looking for VS2013 as it is only supported up to Node.js 8')
@@ -371,10 +373,10 @@ VisualStudioFinder.prototype = {
       versionYear: 2013,
       toolset: 'v120'
     })
-  },
+  }
 
   // Helper - common code for VS2013 and VS2015
-  findOldVS: async function findOldVS (info) {
+  async findOldVS (info) {
     const regVC7 = ['HKLM\\Software\\Microsoft\\VisualStudio\\SxS\\VC7',
       'HKLM\\Software\\Wow6432Node\\Microsoft\\VisualStudio\\SxS\\VC7']
     const regMSBuild = 'HKLM\\Software\\Microsoft\\MSBuild\\ToolsVersions'
@@ -408,14 +410,14 @@ VisualStudioFinder.prototype = {
       this.addLog('- not found')
       return null
     }
-  },
+  }
 
   // After finding a usable version of Visual Studio:
   // - add it to validVersions to be displayed at the end if a specific
   //   version was requested and not found;
   // - check if this is the version that was requested.
   // - check if this matches the Visual Studio Command Prompt
-  checkConfigVersion: function checkConfigVersion (versionYear, vsPath) {
+  checkConfigVersion (versionYear, vsPath) {
     this.validVersions.push(versionYear)
     this.validVersions.push(vsPath)
 
@@ -438,10 +440,4 @@ VisualStudioFinder.prototype = {
   }
 }
 
-const findVisualStudio = async (nodeSemver, configMsvsVersion) => new VisualStudioFinder(nodeSemver, configMsvsVersion).findVisualStudio()
-
-module.exports = findVisualStudio
-module.exports.test = {
-  VisualStudioFinder,
-  findVisualStudio
-}
+module.exports = VisualStudioFinder
diff --git a/lib/node-gyp.js b/lib/node-gyp.js
index c2ce69051f..5e25bf996f 100644
--- a/lib/node-gyp.js
+++ b/lib/node-gyp.js
@@ -4,8 +4,8 @@ const path = require('path')
 const nopt = require('nopt')
 const log = require('./log')
 const childProcess = require('child_process')
-const EE = require('events').EventEmitter
-const { inherits } = require('util')
+const { EventEmitter } = require('events')
+
 const commands = [
   // Module build commands
   'build',
@@ -17,191 +17,172 @@ const commands = [
   'list',
   'remove'
 ]
-const aliases = {
-  ls: 'list',
-  rm: 'remove'
-}
 
-function gyp () {
-  return new Gyp()
-}
+class Gyp extends EventEmitter {
+  /**
+   * Export the contents of the package.json.
+   */
+  package = require('../package.json')
+
+  /**
+   * nopt configuration definitions
+   */
+  configDefs = {
+    help: Boolean, // everywhere
+    arch: String, // 'configure'
+    cafile: String, // 'install'
+    debug: Boolean, // 'build'
+    directory: String, // bin
+    make: String, // 'build'
+    'msvs-version': String, // 'configure'
+    ensure: Boolean, // 'install'
+    solution: String, // 'build' (windows only)
+    proxy: String, // 'install'
+    noproxy: String, // 'install'
+    devdir: String, // everywhere
+    nodedir: String, // 'configure'
+    loglevel: String, // everywhere
+    python: String, // 'configure'
+    'dist-url': String, // 'install'
+    tarball: String, // 'install'
+    jobs: String, // 'build'
+    thin: String, // 'configure'
+    'force-process-config': Boolean // 'configure'
+  }
 
-function Gyp () {
-  this.devDir = ''
+  /**
+   * nopt shorthands
+   */
+  shorthands = {
+    release: '--no-debug',
+    C: '--directory',
+    debug: '--debug',
+    j: '--jobs',
+    silly: '--loglevel=silly',
+    verbose: '--loglevel=verbose',
+    silent: '--loglevel=silent'
+  }
 
-  this.commands = commands.reduce((acc, command) => {
-    acc[command] = (argv) => require('./' + command)(this, argv)
-    return acc
-  }, {})
-}
-inherits(Gyp, EE)
-exports.Gyp = Gyp
-const proto = Gyp.prototype
-
-/**
- * Export the contents of the package.json.
- */
-
-proto.package = require('../package.json')
-
-/**
- * nopt configuration definitions
- */
-
-proto.configDefs = {
-  help: Boolean, // everywhere
-  arch: String, // 'configure'
-  cafile: String, // 'install'
-  debug: Boolean, // 'build'
-  directory: String, // bin
-  make: String, // 'build'
-  'msvs-version': String, // 'configure'
-  ensure: Boolean, // 'install'
-  solution: String, // 'build' (windows only)
-  proxy: String, // 'install'
-  noproxy: String, // 'install'
-  devdir: String, // everywhere
-  nodedir: String, // 'configure'
-  loglevel: String, // everywhere
-  python: String, // 'configure'
-  'dist-url': String, // 'install'
-  tarball: String, // 'install'
-  jobs: String, // 'build'
-  thin: String, // 'configure'
-  'force-process-config': Boolean // 'configure'
-}
+  /**
+   * expose the command aliases for the bin file to use.
+   */
+  aliases = {
+    ls: 'list',
+    rm: 'remove'
+  }
 
-/**
- * nopt shorthands
- */
-
-proto.shorthands = {
-  release: '--no-debug',
-  C: '--directory',
-  debug: '--debug',
-  j: '--jobs',
-  silly: '--loglevel=silly',
-  verbose: '--loglevel=verbose',
-  silent: '--loglevel=silent'
-}
+  constructor (...args) {
+    super(...args)
 
-/**
- * expose the command aliases for the bin file to use.
- */
+    this.devDir = ''
 
-proto.aliases = aliases
+    this.commands = commands.reduce((acc, command) => {
+      acc[command] = (argv) => require('./' + command)(this, argv)
+      return acc
+    }, {})
 
-/**
- * Parses the given argv array and sets the 'opts',
- * 'argv' and 'command' properties.
- */
+    Object.defineProperty(this, 'version', {
+      enumerable: true,
+      get: function () { return this.package.version }
+    })
+  }
 
-proto.parseArgv = function parseOpts (argv) {
-  this.opts = nopt(this.configDefs, this.shorthands, argv)
-  this.argv = this.opts.argv.remain.slice()
+  /**
+   * Parses the given argv array and sets the 'opts',
+   * 'argv' and 'command' properties.
+   */
+  parseArgv (argv) {
+    this.opts = nopt(this.configDefs, this.shorthands, argv)
+    this.argv = this.opts.argv.remain.slice()
 
-  const commands = this.todo = []
+    const commands = this.todo = []
 
-  // create a copy of the argv array with aliases mapped
-  argv = this.argv.map(function (arg) {
+    // create a copy of the argv array with aliases mapped
+    argv = this.argv.map((arg) => {
     // is this an alias?
-    if (arg in this.aliases) {
-      arg = this.aliases[arg]
-    }
-    return arg
-  }, this)
-
-  // process the mapped args into "command" objects ("name" and "args" props)
-  argv.slice().forEach(function (arg) {
-    if (arg in this.commands) {
-      const args = argv.splice(0, argv.indexOf(arg))
-      argv.shift()
-      if (commands.length > 0) {
-        commands[commands.length - 1].args = args
+      if (arg in this.aliases) {
+        arg = this.aliases[arg]
       }
-      commands.push({ name: arg, args: [] })
+      return arg
+    })
+
+    // process the mapped args into "command" objects ("name" and "args" props)
+    argv.slice().forEach((arg) => {
+      if (arg in this.commands) {
+        const args = argv.splice(0, argv.indexOf(arg))
+        argv.shift()
+        if (commands.length > 0) {
+          commands[commands.length - 1].args = args
+        }
+        commands.push({ name: arg, args: [] })
+      }
+    })
+    if (commands.length > 0) {
+      commands[commands.length - 1].args = argv.splice(0)
     }
-  }, this)
-  if (commands.length > 0) {
-    commands[commands.length - 1].args = argv.splice(0)
-  }
 
-  // support for inheriting config env variables from npm
-  const npmConfigPrefix = 'npm_config_'
-  Object.keys(process.env).forEach(function (name) {
-    if (name.indexOf(npmConfigPrefix) !== 0) {
-      return
-    }
-    const val = process.env[name]
-    if (name === npmConfigPrefix + 'loglevel') {
-      log.logger.level = val
-    } else {
+    // support for inheriting config env variables from npm
+    const npmConfigPrefix = 'npm_config_'
+    Object.keys(process.env).forEach((name) => {
+      if (name.indexOf(npmConfigPrefix) !== 0) {
+        return
+      }
+      const val = process.env[name]
+      if (name === npmConfigPrefix + 'loglevel') {
+        log.logger.level = val
+      } else {
       // add the user-defined options to the config
-      name = name.substring(npmConfigPrefix.length)
-      // gyp@741b7f1 enters an infinite loop when it encounters
-      // zero-length options so ensure those don't get through.
-      if (name) {
+        name = name.substring(npmConfigPrefix.length)
+        // gyp@741b7f1 enters an infinite loop when it encounters
+        // zero-length options so ensure those don't get through.
+        if (name) {
         // convert names like force_process_config to force-process-config
-        if (name.includes('_')) {
-          name = name.replace(/_/g, '-')
+          if (name.includes('_')) {
+            name = name.replace(/_/g, '-')
+          }
+          this.opts[name] = val
         }
-        this.opts[name] = val
       }
-    }
-  }, this)
+    })
 
-  if (this.opts.loglevel) {
-    log.logger.level = this.opts.loglevel
+    if (this.opts.loglevel) {
+      log.logger.level = this.opts.loglevel
+    }
+    log.resume()
   }
-  log.resume()
-}
-
-/**
- * Spawns a child process and emits a 'spawn' event.
- */
 
-proto.spawn = function spawn (command, args, opts) {
-  if (!opts) {
-    opts = {}
-  }
-  if (!opts.silent && !opts.stdio) {
-    opts.stdio = [0, 1, 2]
+  /**
+   * Spawns a child process and emits a 'spawn' event.
+   */
+  spawn (command, args, opts) {
+    if (!opts) {
+      opts = {}
+    }
+    if (!opts.silent && !opts.stdio) {
+      opts.stdio = [0, 1, 2]
+    }
+    const cp = childProcess.spawn(command, args, opts)
+    log.info('spawn', command)
+    log.info('spawn args', args)
+    return cp
   }
-  const cp = childProcess.spawn(command, args, opts)
-  log.info('spawn', command)
-  log.info('spawn args', args)
-  return cp
-}
 
-/**
- * Returns the usage instructions for node-gyp.
- */
-
-proto.usage = function usage () {
-  const str = [
-    '',
-    '  Usage: node-gyp <command> [options]',
-    '',
-    '  where <command> is one of:',
-    commands.map(function (c) {
-      return '    - ' + c + ' - ' + require('./' + c).usage
-    }).join('\n'),
-    '',
-    'node-gyp@' + this.version + '  ' + path.resolve(__dirname, '..'),
-    'node@' + process.versions.node
-  ].join('\n')
-  return str
+  /**
+   * Returns the usage instructions for node-gyp.
+   */
+  usage () {
+    return [
+      '',
+      '  Usage: node-gyp <command> [options]',
+      '',
+      '  where <command> is one of:',
+      commands.map((c) => '    - ' + c + ' - ' + require('./' + c).usage).join('\n'),
+      '',
+      'node-gyp@' + this.version + '  ' + path.resolve(__dirname, '..'),
+      'node@' + process.versions.node
+    ].join('\n')
+  }
 }
 
-/**
- * Version number getter.
- */
-
-Object.defineProperty(proto, 'version', {
-  get: function () {
-    return this.package.version
-  },
-  enumerable: true
-})
-
-module.exports = exports = gyp
+module.exports = () => new Gyp()
+module.exports.Gyp = Gyp
diff --git a/test/common.js b/test/common.js
index b714ee2902..f7e2e2a34c 100644
--- a/test/common.js
+++ b/test/common.js
@@ -1,3 +1,17 @@
 const envPaths = require('env-paths')
 
 module.exports.devDir = () => envPaths('node-gyp', { suffix: '' }).cache
+
+module.exports.poison = (object, property) => {
+  function fail () {
+    console.error(Error(`Property ${property} should not have been accessed.`))
+    process.abort()
+  }
+  const descriptor = {
+    configurable: false,
+    enumerable: false,
+    get: fail,
+    set: fail
+  }
+  Object.defineProperty(object, property, descriptor)
+}
diff --git a/test/test-find-python.js b/test/test-find-python.js
index a00ae94057..c5fa35d4bc 100644
--- a/test/test-find-python.js
+++ b/test/test-find-python.js
@@ -4,42 +4,33 @@ delete process.env.PYTHON
 
 const { describe, it } = require('mocha')
 const assert = require('assert')
-const { test: { PythonFinder, findPython: testFindPython } } = require('../lib/find-python')
+const PythonFinder = require('../lib/find-python')
 const { execFile } = require('../lib/util')
+const { poison } = require('./common')
 
-describe('find-python', function () {
-  it('find python', async function () {
-    const found = await testFindPython(null)
-    const [err, stdout, stderr] = await execFile(found, ['-V'], { encoding: 'utf-8' })
-    assert.strictEqual(err, null)
-    assert.ok(/Python 3/.test(stdout))
-    assert.strictEqual(stderr, '')
-  })
-
-  function poison (object, property) {
-    function fail () {
-      console.error(Error(`Property ${property} should not have been accessed.`))
-      process.abort()
-    }
-    const descriptor = {
-      configurable: false,
-      enumerable: false,
-      get: fail,
-      set: fail
-    }
-    Object.defineProperty(object, property, descriptor)
+class TestPythonFinder extends PythonFinder {
+  constructor (...args) {
+    super(...args)
+    delete this.env.NODE_GYP_FORCE_PYTHON
   }
 
-  function TestPythonFinder () { PythonFinder.apply(this, arguments) }
-  TestPythonFinder.prototype = Object.create(PythonFinder.prototype)
-  delete TestPythonFinder.prototype.env.NODE_GYP_FORCE_PYTHON
-  const findPython = async (f) => {
+  async findPython () {
     try {
-      return { err: null, python: await f.findPython() }
+      return { err: null, python: await super.findPython() }
     } catch (err) {
       return { err, python: null }
     }
   }
+}
+
+describe('find-python', function () {
+  it('find python', async function () {
+    const found = await PythonFinder.findPython(null)
+    const [err, stdout, stderr] = await execFile(found, ['-V'], { encoding: 'utf-8' })
+    assert.strictEqual(err, null)
+    assert.ok(/Python 3/.test(stdout))
+    assert.strictEqual(stderr, '')
+  })
 
   it('find python - python', async function () {
     const f = new TestPythonFinder('python')
@@ -55,7 +46,7 @@ describe('find-python', function () {
       return [null, '/path/python']
     }
 
-    const { err, python } = await findPython(f)
+    const { err, python } = await f.findPython()
     assert.strictEqual(err, null)
     assert.strictEqual(python, '/path/python')
   })
@@ -72,7 +63,7 @@ describe('find-python', function () {
       }
     }
 
-    const { err } = await findPython(f)
+    const { err } = await f.findPython()
     assert.ok(/Could not find any Python/.test(err))
     assert.ok(/not supported/i.test(f.errorLog))
   })
@@ -89,7 +80,7 @@ describe('find-python', function () {
       }
     }
 
-    const { err } = await findPython(f)
+    const { err } = await f.findPython()
     assert.ok(/Could not find any Python/.test(err))
     assert.ok(/not in PATH/.test(f.errorLog))
   })
@@ -107,7 +98,7 @@ describe('find-python', function () {
       }
     }
 
-    const { err } = await findPython(f)
+    const { err } = await f.findPython()
     assert.ok(/Could not find any Python/.test(err))
     assert.ok(/not in PATH/.test(f.errorLog))
   })
@@ -136,7 +127,7 @@ describe('find-python', function () {
         assert.fail()
       }
     }
-    const { err, python } = await findPython(f)
+    const { err, python } = await f.findPython()
     assert.strictEqual(err, null)
     assert.strictEqual(python, 'Z:\\snake.exe')
   })
@@ -159,7 +150,7 @@ describe('find-python', function () {
         assert.fail()
       }
     }
-    const { err, python } = await findPython(f)
+    const { err, python } = await f.findPython()
     assert.strictEqual(err, null)
     assert.ok(python === expectedProgram)
   })
@@ -177,7 +168,7 @@ describe('find-python', function () {
         assert.fail()
       }
     }
-    const { err } = await findPython(f)
+    const { err } = await f.findPython()
     assert.ok(/Could not find any Python/.test(err))
     assert.ok(/not in PATH/.test(f.errorLog))
   })
diff --git a/test/test-find-visualstudio.js b/test/test-find-visualstudio.js
index cb065e52cf..08e9438c45 100644
--- a/test/test-find-visualstudio.js
+++ b/test/test-find-visualstudio.js
@@ -4,34 +4,20 @@ const { describe, it } = require('mocha')
 const assert = require('assert')
 const fs = require('fs')
 const path = require('path')
-const { test: { VisualStudioFinder } } = require('../lib/find-visualstudio')
+const VisualStudioFinder = require('../lib/find-visualstudio')
+const { poison } = require('./common')
 
 const semverV1 = { major: 1, minor: 0, patch: 0 }
 
 delete process.env.VCINSTALLDIR
 
-function poison (object, property) {
-  function fail () {
-    console.error(Error(`Property ${property} should not have been accessed.`))
-    process.abort()
-  }
-  const descriptor = {
-    configurable: false,
-    enumerable: false,
-    get: fail,
-    set: fail
-  }
-  Object.defineProperty(object, property, descriptor)
-}
-
-function TestVisualStudioFinder () { VisualStudioFinder.apply(this, arguments) }
-TestVisualStudioFinder.prototype = Object.create(VisualStudioFinder.prototype)
-
-const findVisualStudio = async (finder) => {
-  try {
-    return { err: null, info: await finder.findVisualStudio() }
-  } catch (err) {
-    return { err, info: null }
+class TestVisualStudioFinder extends VisualStudioFinder {
+  async findVisualStudio () {
+    try {
+      return { err: null, info: await super.findVisualStudio() }
+    } catch (err) {
+      return { err, info: null }
+    }
   }
 }
 
@@ -62,7 +48,7 @@ describe('find-visualstudio', function () {
       throw new Error()
     }
 
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info, {
       msBuild: 'C:\\MSBuild12\\MSBuild.exe',
@@ -102,7 +88,7 @@ describe('find-visualstudio', function () {
       throw new Error()
     }
 
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.ok(/find .* Visual Studio/i.test(err), 'expect error')
     assert.ok(!info, 'no data')
   })
@@ -129,7 +115,7 @@ describe('find-visualstudio', function () {
       }
       throw new Error()
     }
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info, {
       msBuild: 'C:\\MSBuild14\\MSBuild.exe',
@@ -228,7 +214,7 @@ describe('find-visualstudio', function () {
       const data = fs.readFileSync(file)
       return finder.parseData(null, data, '')
     }
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info, {
       msBuild: 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\' +
@@ -254,7 +240,7 @@ describe('find-visualstudio', function () {
       const data = fs.readFileSync(file)
       return finder.parseData(null, data, '')
     }
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info, {
       msBuild: 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\' +
@@ -279,7 +265,7 @@ describe('find-visualstudio', function () {
       const data = fs.readFileSync(file)
       return finder.parseData(null, data, '')
     }
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info, {
       msBuild: 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\' +
@@ -305,7 +291,7 @@ describe('find-visualstudio', function () {
       const data = fs.readFileSync(file)
       return finder.parseData(null, data, '')
     }
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info, {
       msBuild: 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\' +
@@ -331,7 +317,7 @@ describe('find-visualstudio', function () {
       const data = fs.readFileSync(file)
       return finder.parseData(null, data, '')
     }
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info, {
       msBuild: 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\' +
@@ -357,7 +343,7 @@ describe('find-visualstudio', function () {
       const data = fs.readFileSync(file)
       return finder.parseData(null, data, '')
     }
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info, {
       msBuild: 'C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\' +
@@ -392,7 +378,7 @@ describe('find-visualstudio', function () {
       const data = fs.readFileSync(file)
       return finder.parseData(null, data, '')
     }
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info, {
       msBuild: msBuildPath,
@@ -456,7 +442,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, 'AABB')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.ok(/find .* Visual Studio/i.test(err), 'expect error')
     assert.ok(!info, 'no data')
   })
@@ -465,7 +451,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, '2013')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.versionYear, 2013)
   })
@@ -474,7 +460,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, 'C:\\VS2013')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.path, 'C:\\VS2013')
   })
@@ -483,7 +469,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, '2015')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.versionYear, 2015)
   })
@@ -492,7 +478,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, 'C:\\VS2015')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.path, 'C:\\VS2015')
   })
@@ -501,7 +487,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, '2017')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.versionYear, 2017)
   })
@@ -511,7 +497,7 @@ describe('find-visualstudio', function () {
       'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Community')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.path,
       'C:\\Program Files (x86)\\Microsoft Visual Studio\\2017\\Community')
@@ -521,7 +507,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, '2019')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.versionYear, 2019)
   })
@@ -531,7 +517,7 @@ describe('find-visualstudio', function () {
       'C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\BuildTools')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.path,
       'C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\BuildTools')
@@ -545,7 +531,7 @@ describe('find-visualstudio', function () {
     }
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.versionYear, 2022)
   })
@@ -555,7 +541,7 @@ describe('find-visualstudio', function () {
       'c:\\program files (x86)\\microsoft visual studio\\2019\\BUILDTOOLS')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.path,
       'C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\BuildTools')
@@ -569,7 +555,7 @@ describe('find-visualstudio', function () {
     }
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.versionYear, 2022)
   })
@@ -582,7 +568,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, null)
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.path, 'C:\\VS2015')
   })
@@ -594,7 +580,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, null)
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.path,
       'C:\\Program Files (x86)\\Microsoft Visual Studio\\2019\\BuildTools')
@@ -607,7 +593,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, null)
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.ok(/find .* Visual Studio/i.test(err), 'expect error')
     assert.ok(!info, 'no data')
   })
@@ -618,7 +604,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, 'C:\\VS2015')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.strictEqual(err, null)
     assert.deepStrictEqual(info.path, 'C:\\VS2015')
   })
@@ -630,7 +616,7 @@ describe('find-visualstudio', function () {
     const finder = new TestVisualStudioFinder(semverV1, 'C:\\VS2015')
 
     allVsVersions(finder)
-    const { err, info } = await findVisualStudio(finder)
+    const { err, info } = await finder.findVisualStudio()
     assert.ok(/find .* Visual Studio/i.test(err), 'expect error')
     assert.ok(!info, 'no data')
   })