TypeScript ramda.tap函數代碼示例

function checkOneBrowser(browser: Browser) {
  const platform = os.platform()
  const pickBrowserProps = pick([
    'name',
    'displayName',
    'type',
    'version',
    'path'
  ])

  const logBrowser = (props: any) => {
    log('setting major version for %j', props)
  }

  const failed = (err: NotInstalledError) => {
    if (err.notInstalled) {
      log('browser %s not installed', browser.name)
      return false
    }
    throw err
  }

  log('checking one browser %s', browser.name)
  return lookup(platform, browser)
    .then(merge(browser))
    .then(pickBrowserProps)
    .then(tap(logBrowser))
    .then(setMajorVersion)
    .catch(failed)
}

 .then(exists => {
   log('found %s ?', exePath, exists)
   if (!exists) {
     throw notInstalledErr(`Browser ${name} file not found at ${exePath}`)
   }
   // on Windows using "--version" seems to always start the full
   // browser, no matter what one does.
   const args: [string] = [
     'datafile',
     'where',
     `name="${doubleEscape(exePath)}"`,
     'get',
     'Version',
     '/value'
   ]
   return execa('wmic', args)
     .then(result => result.stdout)
     .then(trim)
     .then(tap(log))
     .then(getVersion)
     .then((version: string) => {
       log("browser %s at '%s' version %s", name, exePath, version)
       return {
         name,
         version,
         path: exePath
       }
     })
 })

    .then(exists => {
      log('found %s ?', exePath, exists)

      if (!exists) {
        throw notInstalledErr(`Browser ${name} file not found at ${exePath}`)
      }

      return getVersionString(exePath)
        .then(tap(log))
        .then(getVersion)
        .then((version: string) => {
          log("browser %s at '%s' version %s", name, exePath, version)
          return {
            name,
            version,
            path: exePath
          } as FoundBrowser
        })
    })

export function mdfind(id: string): Promise<string> {
  const cmd = `mdfind 'kMDItemCFBundleIdentifier=="${id}"' | head -1`
  log('looking for bundle id %s using command: %s', id, cmd)

  const logFound = (str: string) => {
    log('found %s at %s', id, str)
    return str
  }

  const failedToFind = () => {
    log('could not find %s', id)
    throw notInstalledErr(id)
  }

  return execa
    .shell(cmd)
    .then(result => result.stdout)
    .then(tap(logFound))
    .catch(failedToFind)
}

function getLinuxBrowser(
  name: string,
  binary: string,
  versionRegex: RegExp
): Promise<FoundBrowser> {
  const getVersion = (stdout: string) => {
    const m = versionRegex.exec(stdout)
    if (m) {
      return m[1]
    }
    log(
      'Could not extract version from %s using regex %s',
      stdout,
      versionRegex
    )
    return notInstalledErr(binary)
  }

  const returnError = (err: Error) => {
    log('Could not detect browser %s', err.message)
    return notInstalledErr(binary)
  }

  const cmd = `${binary} --version`
  log('looking using command "%s"', cmd)
  return execa
    .shell(cmd)
    .then(result => result.stdout)
    .then(trim)
    .then(tap(log))
    .then(getVersion)
    .then((version: string) => {
      return {
        name,
        version,
        path: binary
      }
    })
    .catch(returnError)
}

function getLinuxBrowser(
  name: string,
  binary: string,
  versionRegex: RegExp
): Promise<FoundBrowser> {
  const getVersion = (stdout: string) => {
    const m = versionRegex.exec(stdout)
    if (m) {
      return m[1]
    }
    log(
      'Could not extract version from %s using regex %s',
      stdout,
      versionRegex
    )
    throw notInstalledErr(binary)
  }

  const logAndThrowError = (err: Error) => {
    log(
      'Received error detecting browser binary: "%s" with error:',
      binary,
      err.message
    )
    throw notInstalledErr(binary)
  }

  return getVersionString(binary)
    .then(tap(log))
    .then(getVersion)
    .then((version: string) => {
      return {
        name,
        version,
        path: binary
      } as FoundBrowser
    })
    .catch(logAndThrowError)
}