add node_modules to address #4364

1 files changed, 131 insertions, 0 deletions

diff --git a/node_modules/v8flags/index.js b/node_modules/v8flags/index.js
new file mode 100644
index 000000000..a368b5ced
--- /dev/null
+++ b/node_modules/v8flags/index.js
@@ -0,0 +1,131 @@
+// this entire module is depressing. i should have spent my time learning
+// how to patch v8 so that these options would just be available on the
+// process object.
+
+const os = require('os');
+const fs = require('fs');
+const path = require('path');
+const execFile = require('child_process').execFile;
+const env = process.env;
+const user = env.LOGNAME || env.USER || env.LNAME || env.USERNAME;
+const configfile = '.v8flags.'+process.versions.v8+'.'+user+'.json';
+const exclusions = ['--help'];
+
+const failureMessage = [
+  'Unable to cache a config file for v8flags to a your home directory',
+  'or a temporary folder. To fix this problem, please correct your',
+  'environment by setting HOME=/path/to/home or TEMP=/path/to/temp.',
+  'NOTE: the user running this must be able to access provided path.',
+  'If all else fails, please open an issue here:',
+  'http://github.com/tkellen/js-v8flags'
+].join('\n');
+
+function fail (err) {
+  err.message += '\n\n' + failureMessage;
+  return err;
+}
+
+function openConfig (cb) {
+  var userHome = require('user-home');
+  if (!userHome) {
+    return tryOpenConfig(path.join(os.tmpdir(), configfile), cb);
+  }
+
+  tryOpenConfig(path.join(userHome, configfile), function (err, fd) {
+    if (err) return tryOpenConfig(path.join(os.tmpdir(), configfile), cb);
+    return cb(null, fd);
+  });
+}
+
+function tryOpenConfig (configpath, cb) {
+  try {
+    // if the config file is valid, it should be json and therefore
+    // node should be able to require it directly. if this doesn't
+    // throw, we're done!
+    content = require(configpath);
+    process.nextTick(function () {
+      cb(null, content);
+    });
+  } catch (e) {
+    // if requiring the config file failed, maybe it doesn't exist, or
+    // perhaps it has become corrupted. instead of calling back with the
+    // content of the file, call back with a file descriptor that we can
+    // write the cached data to
+    fs.open(configpath, 'w+', function (err, fd) {
+      if (err) {
+        return cb(err);
+      }
+      return cb(null, fd);
+    });
+  }
+}
+
+// i can't wait for the day this whole module is obsolete because these
+// options are available on the process object. this executes node with
+// `--v8-options` and parses the result, returning an array of command
+// line flags.
+function getFlags (cb) {
+  execFile(process.execPath, ['--v8-options'], function (execErr, result) {
+    if (execErr) {
+      return cb(execErr);
+    }
+    var flags = result.match(/\s\s--(\w+)/gm).map(function (match) {
+      return match.substring(2);
+    }).filter(function (name) {
+      return exclusions.indexOf(name) === -1;
+    });
+    return cb(null, flags);
+  });
+}
+
+// write some json to a file descriptor. if this fails, call back
+// with both the error and the data that was meant to be written.
+function writeConfig (fd, flags, cb) {
+  var buf = new Buffer(JSON.stringify(flags));
+  return fs.write(fd, buf, 0, buf.length, 0 , function (writeErr) {
+    fs.close(fd, function (closeErr) {
+      var err = writeErr || closeErr;
+      if (err) {
+        return cb(fail(err), flags);
+      }
+      return cb(null, flags);
+    });
+  });
+}
+
+module.exports = function (cb) {
+  // bail early if this is not node
+  var isElectron = process.versions && process.versions.electron;
+  if (isElectron) {
+    return process.nextTick(function () {
+      cb(null, []);
+    });
+  }
+
+  // attempt to open/read cache file
+  openConfig(function (openErr, result) {
+    if (!openErr && typeof result !== 'number') {
+      return cb(null, result);
+    }
+    // if the result is not an array, we need to go fetch
+    // the flags by invoking node with `--v8-options`
+    getFlags(function (flagsErr, flags) {
+      // if there was an error fetching the flags, bail immediately
+      if (flagsErr) {
+        return cb(flagsErr);
+      }
+      // if there was a problem opening the config file for writing
+      // throw an error but include the flags anyway so that users
+      // can continue to execute (at the expense of having to fetch
+      // flags on every run until they fix the underyling problem).
+      if (openErr) {
+        return cb(fail(openErr), flags);
+      }
+      // write the config file to disk so subsequent runs can read
+      // flags out of a cache file.
+      return writeConfig(result, flags, cb);
+    });
+  });
+};
+
+module.exports.configfile = configfile;