flow like the river

VISUALIZACION/node_modules/browserslist/node.js

@@ -0,0 +1,262 @@
+var region = require('caniuse-lite/dist/unpacker/region').default
+var path = require('path')
+var fs = require('fs')
+
+var BrowserslistError = require('./error')
+
+var IS_SECTION = /^\s*\[(.+)\]\s*$/
+var CONFIG_PATTERN = /^browserslist-config-/
+var SCOPED_CONFIG__PATTERN = /@[^./]+\/browserslist-config(-|$)/
+var FORMAT = 'Browserslist config should be a string or an array ' +
+             'of strings with browser queries'
+
+var filenessCache = { }
+var configCache = { }
+
+function checkExtend (name) {
+  var use = ' Use `dangerousExtend` option to disable.'
+  if (!CONFIG_PATTERN.test(name) && !SCOPED_CONFIG__PATTERN.test(name)) {
+    throw new BrowserslistError(
+      'Browserslist config needs `browserslist-config-` prefix. ' + use)
+  }
+  if (name.indexOf('.') !== -1) {
+    throw new BrowserslistError(
+      '`.` not allowed in Browserslist config name. ' + use)
+  }
+  if (name.indexOf('node_modules') !== -1) {
+    throw new BrowserslistError(
+      '`node_modules` not allowed in Browserslist config.' + use)
+  }
+}
+
+function isFile (file) {
+  if (file in filenessCache) {
+    return filenessCache[file]
+  }
+  var result = fs.existsSync(file) && fs.statSync(file).isFile()
+  if (!process.env.BROWSERSLIST_DISABLE_CACHE) {
+    filenessCache[file] = result
+  }
+  return result
+}
+
+function eachParent (file, callback) {
+  var loc = path.resolve(file)
+  do {
+    var result = callback(loc)
+    if (typeof result !== 'undefined') return result
+  } while (loc !== (loc = path.dirname(loc)))
+  return undefined
+}
+
+function check (section) {
+  if (Array.isArray(section)) {
+    for (var i = 0; i < section.length; i++) {
+      if (typeof section[i] !== 'string') {
+        throw new BrowserslistError(FORMAT)
+      }
+    }
+  } else if (typeof section !== 'string') {
+    throw new BrowserslistError(FORMAT)
+  }
+}
+
+function pickEnv (config, opts) {
+  if (typeof config !== 'object') return config
+
+  var name
+  if (typeof opts.env === 'string') {
+    name = opts.env
+  } else if (process.env.BROWSERSLIST_ENV) {
+    name = process.env.BROWSERSLIST_ENV
+  } else if (process.env.NODE_ENV) {
+    name = process.env.NODE_ENV
+  } else {
+    name = 'production'
+  }
+
+  return config[name] || config.defaults
+}
+
+function parsePackage (file) {
+  var config = JSON.parse(fs.readFileSync(file))
+  if (config.browserlist && !config.browserslist) {
+    throw new BrowserslistError(
+      '`browserlist` key instead of `browserslist` in ' + file)
+  }
+  var list = config.browserslist
+  if (Array.isArray(list)) {
+    list = { defaults: list }
+  }
+
+  for (var i in list) {
+    check(list[i])
+  }
+
+  return list
+}
+
+module.exports = {
+  loadQueries: function loadQueries (context, name) {
+    if (!context.dangerousExtend) checkExtend(name)
+    // eslint-disable-next-line security/detect-non-literal-require
+    var queries = require(require.resolve(name, { paths: ['.'] }))
+    if (!Array.isArray(queries)) {
+      throw new BrowserslistError(
+        '`' + name + '` config exports not an array of queries')
+    }
+    return queries
+  },
+
+  getStat: function getStat (opts) {
+    var stats
+    if (opts.stats) {
+      stats = opts.stats
+    } else if (process.env.BROWSERSLIST_STATS) {
+      stats = process.env.BROWSERSLIST_STATS
+    } else if (opts.path && path.resolve && fs.existsSync) {
+      stats = eachParent(opts.path, function (dir) {
+        var file = path.join(dir, 'browserslist-stats.json')
+        return isFile(file) ? file : undefined
+      })
+    }
+
+    if (typeof stats === 'string') {
+      try {
+        stats = JSON.parse(fs.readFileSync(stats))
+      } catch (e) {
+        throw new BrowserslistError('Can\'t read ' + stats)
+      }
+    }
+
+    if (stats && 'dataByBrowser' in stats) {
+      stats = stats.dataByBrowser
+    }
+
+    return stats
+  },
+
+  loadConfig: function loadConfig (opts) {
+    if (process.env.BROWSERSLIST) {
+      return process.env.BROWSERSLIST
+    } else if (opts.config || process.env.BROWSERSLIST_CONFIG) {
+      var file = opts.config || process.env.BROWSERSLIST_CONFIG
+      if (path.basename(file) === 'package.json') {
+        return pickEnv(parsePackage(file), opts)
+      } else {
+        return pickEnv(module.exports.readConfig(file), opts)
+      }
+    } else if (opts.path) {
+      return pickEnv(module.exports.findConfig(opts.path), opts)
+    } else {
+      return undefined
+    }
+  },
+
+  loadCountry: function loadCountry (usage, country) {
+    var code = country.replace(/[^\w-]/g, '')
+    if (!usage[code]) {
+      // eslint-disable-next-line security/detect-non-literal-require
+      var compressed = require('caniuse-lite/data/regions/' + code + '.js')
+      var data = region(compressed)
+      usage[country] = { }
+      for (var i in data) {
+        for (var j in data[i]) {
+          usage[country][i + ' ' + j] = data[i][j]
+        }
+      }
+    }
+  },
+
+  parseConfig: function parseConfig (string) {
+    var result = { defaults: [] }
+    var sections = ['defaults']
+
+    string.toString()
+      .replace(/#[^\n]*/g, '')
+      .split(/\n/)
+      .map(function (line) {
+        return line.trim()
+      })
+      .filter(function (line) {
+        return line !== ''
+      })
+      .forEach(function (line) {
+        if (IS_SECTION.test(line)) {
+          sections = line.match(IS_SECTION)[1].trim().split(' ')
+          sections.forEach(function (section) {
+            if (result[section]) {
+              throw new BrowserslistError(
+                'Dublicate section ' + section + ' in Browserslist config')
+            }
+            result[section] = []
+          })
+        } else {
+          sections.forEach(function (section) {
+            result[section].push(line)
+          })
+        }
+      })
+
+    return result
+  },
+
+  readConfig: function readConfig (file) {
+    if (!isFile(file)) {
+      throw new BrowserslistError('Can\'t read ' + file + ' config')
+    }
+    return module.exports.parseConfig(fs.readFileSync(file))
+  },
+
+  findConfig: function findConfig (from) {
+    from = path.resolve(from)
+
+    var cacheKey = isFile(from) ? path.dirname(from) : from
+    if (cacheKey in configCache) {
+      return configCache[cacheKey]
+    }
+
+    var resolved = eachParent(from, function (dir) {
+      var config = path.join(dir, 'browserslist')
+      var pkg = path.join(dir, 'package.json')
+      var rc = path.join(dir, '.browserslistrc')
+
+      var pkgBrowserslist
+      if (isFile(pkg)) {
+        try {
+          pkgBrowserslist = parsePackage(pkg)
+        } catch (e) {
+          if (e.name === 'BrowserslistError') throw e
+          console.warn(
+            '[Browserslist] Could not parse ' + pkg + '. Ignoring it.')
+        }
+      }
+
+      if (isFile(config) && pkgBrowserslist) {
+        throw new BrowserslistError(
+          dir + ' contains both browserslist and package.json with browsers')
+      } else if (isFile(rc) && pkgBrowserslist) {
+        throw new BrowserslistError(
+          dir + ' contains both .browserslistrc and package.json with browsers')
+      } else if (isFile(config) && isFile(rc)) {
+        throw new BrowserslistError(
+          dir + ' contains both .browserslistrc and browserslist')
+      } else if (isFile(config)) {
+        return module.exports.readConfig(config)
+      } else if (isFile(rc)) {
+        return module.exports.readConfig(rc)
+      } else {
+        return pkgBrowserslist
+      }
+    })
+    if (!process.env.BROWSERSLIST_DISABLE_CACHE) {
+      configCache[cacheKey] = resolved
+    }
+    return resolved
+  },
+
+  clearCaches: function clearCaches () {
+    filenessCache = { }
+    configCache = { }
+  }
+}