All files / lib/internal/modules/cjs helpers.js

99.48% Statements 193/194
94.74% Branches 36/38
100% Functions 12/12
99.48% Lines 193/194

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 136x 4543x 136x 136x 136x 136x 136x 107138x 107138x 107138x 72459x 72459x 72459x 72459x 72459x 107138x 136x 136x 136x 136x 136x 31322x 31322x 31322x 31322x 31322x 12x 12x 12x 12x 8x 8x 8x 3x 8x 3x 3x 2x 2x 2x 1x 1x 1x 3x 1x 1x   1x 1x 1x 1x 1x 1x 3x 5x 2x 2x 2x 2x 2x 2x 3x 12x 31322x 31310x 152305x 31310x 31310x 31322x 31322x 107x 107x 107x 31322x 31322x 31322x 31322x 74x 74x 74x 31322x 31322x 31322x 31322x 31322x 31322x 31322x 31322x 31322x 31322x 31322x 31322x 136x 136x 136x 136x 136x 136x 4028x 4028x 1x 1x 4028x 4028x 136x 571x 571x 571x 571x 46490x 46490x 46490x 46490x 46490x 25939x 25939x 20551x 20551x 20551x 20551x 20551x 20551x 20551x 303x 303x 303x 303x 20551x 20551x 20551x 20551x 384x 384x 384x 384x 384x 384x 384x 384x 384x 384x 384x 384x 384x 20551x 20551x 20551x 20551x 20551x 571x 571x 136x 31399x 31399x 30546x 30546x 853x 31399x 136x 136x 136x 136x 136x 136x 136x 136x 136x  
'use strict';
 
const {
  ArrayPrototypeForEach,
  ArrayPrototypeJoin,
  ObjectDefineProperty,
  ObjectPrototypeHasOwnProperty,
  SafeMap,
  SafeSet,
  StringPrototypeCharCodeAt,
  StringPrototypeIncludes,
  StringPrototypeSlice,
  StringPrototypeStartsWith,
} = primordials;
const {
  ERR_MANIFEST_DEPENDENCY_MISSING,
  ERR_UNKNOWN_BUILTIN_MODULE
} = require('internal/errors').codes;
const { NativeModule } = require('internal/bootstrap/loaders');
 
const { validateString } = require('internal/validators');
const path = require('path');
const { pathToFileURL, fileURLToPath, URL } = require('internal/url');
 
const { getOptionValue } = require('internal/options');
const userConditions = getOptionValue('--conditions');
 
let debug = require('internal/util/debuglog').debuglog('module', (fn) => {
  debug = fn;
});
 
// TODO: Use this set when resolving pkg#exports conditions in loader.js.
const cjsConditions = new SafeSet(['require', 'node', ...userConditions]);
 
function loadNativeModule(filename, request) {
  const mod = NativeModule.map.get(filename);
  if (mod?.canBeRequiredByUsers) {
    debug('load native module %s', request);
    // compileForPublicLoader() throws if mod.canBeRequiredByUsers is false:
    mod.compileForPublicLoader();
    return mod;
  }
}
 
// Invoke with makeRequireFunction(module) where |module| is the Module object
// to use as the context for the require() function.
// Use redirects to set up a mapping from a policy and restrict dependencies
const urlToFileCache = new SafeMap();
function makeRequireFunction(mod, redirects) {
  const Module = mod.constructor;
 
  let require;
  if (redirects) {
    const id = mod.filename || mod.id;
    const conditions = cjsConditions;
    const { resolve, reaction } = redirects;
    require = function require(specifier) {
      let missing = true;
      const destination = resolve(specifier, conditions);
      if (destination === true) {
        missing = false;
      } else if (destination) {
        const href = destination.href;
        if (destination.protocol === 'node:') {
          const specifier = destination.pathname;
          const mod = loadNativeModule(specifier, href);
          if (mod && mod.canBeRequiredByUsers) {
            return mod.exports;
          }
          throw new ERR_UNKNOWN_BUILTIN_MODULE(specifier);
        } else if (destination.protocol === 'file:') {
          let filepath;
          if (urlToFileCache.has(href)) {
            filepath = urlToFileCache.get(href);
          } else {
            filepath = fileURLToPath(destination);
            urlToFileCache.set(href, filepath);
          }
          return mod.require(filepath);
        }
      }
      if (missing) {
        reaction(new ERR_MANIFEST_DEPENDENCY_MISSING(
          id,
          specifier,
          ArrayPrototypeJoin([...conditions], ', ')
        ));
      }
      return mod.require(specifier);
    };
  } else {
    require = function require(path) {
      return mod.require(path);
    };
  }
 
  function resolve(request, options) {
    validateString(request, 'request');
    return Module._resolveFilename(request, mod, false, options);
  }
 
  require.resolve = resolve;
 
  function paths(request) {
    validateString(request, 'request');
    return Module._resolveLookupPaths(request, mod);
  }
 
  resolve.paths = paths;
 
  require.main = process.mainModule;
 
  // Enable support to add extra extension types.
  require.extensions = Module._extensions;
 
  require.cache = Module._cache;
 
  return require;
}
 
/**
 * Remove byte order marker. This catches EF BB BF (the UTF-8 BOM)
 * because the buffer-to-string conversion in `fs.readFileSync()`
 * translates it to FEFF, the UTF-16 BOM.
 */
function stripBOM(content) {
  if (StringPrototypeCharCodeAt(content) === 0xFEFF) {
    content = StringPrototypeSlice(content, 1);
  }
  return content;
}
 
function addBuiltinLibsToObject(object) {
  // Make built-in modules available directly (loaded lazily).
  const { builtinModules } = require('internal/modules/cjs/loader').Module;
  ArrayPrototypeForEach(builtinModules, (name) => {
    // Neither add underscored modules, nor ones that contain slashes (e.g.,
    // 'fs/promises') or ones that are already defined.
    if (StringPrototypeStartsWith(name, '_') ||
        StringPrototypeIncludes(name, '/') ||
        ObjectPrototypeHasOwnProperty(object, name)) {
      return;
    }
    // Goals of this mechanism are:
    // - Lazy loading of built-in modules
    // - Having all built-in modules available as non-enumerable properties
    // - Allowing the user to re-assign these variables as if there were no
    //   pre-existing globals with the same name.
 
    const setReal = (val) => {
      // Deleting the property before re-assigning it disables the
      // getter/setter mechanism.
      delete object[name];
      object[name] = val;
    };
 
    ObjectDefineProperty(object, name, {
      get: () => {
        const lib = require(name);
 
        // Disable the current getter/setter and set up a new
        // non-enumerable property.
        delete object[name];
        ObjectDefineProperty(object, name, {
          get: () => lib,
          set: setReal,
          configurable: true,
          enumerable: false
        });
 
        return lib;
      },
      set: setReal,
      configurable: true,
      enumerable: false
    });
  });
}
 
function normalizeReferrerURL(referrer) {
  if (typeof referrer === 'string' && path.isAbsolute(referrer)) {
    return pathToFileURL(referrer).href;
  }
  return new URL(referrer).href;
}
 
module.exports = {
  addBuiltinLibsToObject,
  cjsConditions,
  loadNativeModule,
  makeRequireFunction,
  normalizeReferrerURL,
  stripBOM,
};