chore: use arrows stage 2

.travis.yml

@@ -31,4 +31,5 @@ script:
   - docker run -d -e MYSQL_ALLOW_EMPTY_PASSWORD=1 -e MYSQL_DATABASE=test -p 33306:3306 mysql:5.7
   - MYSQL_PORT=33306 node tools/wait-up.js
   - yarn --version
+  - if [ "$LINT" = "1" ]; then yarn run lint; fi
   - MYSQL_PORT=33306 yarn run test:raw

appveyor.yml

@@ -32,6 +32,7 @@ before_test:
 
 test_script:
   - mysql --version
+  - if "%LINT%"=="1" (yarn run lint)
   - node test/run.js
   - SET MYSQL_USE_COMPRESSION=1
   - node test/run.js

benchmarks/ping-pong-client.js

@@ -3,15 +3,15 @@
 const net = require('net');
 let count = 0;
 const byte = Buffer.from([0x33]);
-function pong() {
+function pong(connection) {
   count++;
-  this.write(byte);
+  connection.write(byte);
 }
 
 const c = net.connect(3334);
 c.setNoDelay(true);
-c.ondata = pong;
-pong.apply(c);
+c.ondata = () => pong(c);
+pong(c);
 
 setInterval(() => {
   console.log(count);

benchmarks/ping-pong-server.js

@@ -3,13 +3,13 @@
 const net = require('net');
 
 const byte = Buffer.from([0x33]);
-function pong() {
-  this.write(byte);
+function pong(conn) {
+  conn.write(byte);
 }
 
 net
   .createServer(s => {
     s.setNoDelay(true);
-    s.ondata = pong;
+    s.ondata = () => pong(s);
   })
   .listen(3334);

benchmarks/ping-pong-uv.js

@@ -9,9 +9,9 @@ function pong(sock) {
   writeReq.oncomplete = noop;
 }
 
-function ping() {
+function ping(conn) {
   count++;
-  pong(this);
+  pong(conn);
 }
 
 const port = 3334;
@@ -25,7 +25,7 @@ req.oncomplete = function() {
   console.log('connected');
   pong(client);
 };
-client.onread = ping;
+client.onread = () => ping(client);
 client.readStart();
 
 setInterval(() => {

lib/compressed_protocol.js

@@ -7,6 +7,7 @@ const zlib = require('zlib');
 const PacketParser = require('./packet_parser.js');
 
 function handleCompressedPacket(packet) {
+  // eslint-disable-next-line consistent-this, no-invalid-this
   const connection = this;
   const deflatedLength = packet.readInt24();
   const body = packet.readBuffer();
@@ -44,13 +45,15 @@ function writeCompressed(buffer) {
   if (buffer.length > MAX_COMPRESSED_LENGTH) {
     for (start = 0; start < buffer.length; start += MAX_COMPRESSED_LENGTH) {
       writeCompressed.call(
+        // eslint-disable-next-line no-invalid-this
         this,
         buffer.slice(start, start + MAX_COMPRESSED_LENGTH)
       );
     }
     return;
   }
 
+  // eslint-disable-next-line no-invalid-this, consistent-this
   const connection = this;
 
   let packetLen = buffer.length;

lib/packets/execute.js

@@ -22,6 +22,7 @@ function toParameter(value, encoding) {
   let type = Types.VAR_STRING;
   let length;
   let writer = function(value) {
+    // eslint-disable-next-line no-invalid-this
     return Packet.prototype.writeLengthCodedString.call(this, value, encoding);
   };
   if (value !== null) {
@@ -77,7 +78,6 @@ class Execute {
   }
 
   toPacket() {
-    const self = this;
     // TODO: don't try to calculate packet length in advance, allocate some big buffer in advance (header + 256 bytes?)
     // and copy + reallocate if not enough
     // 0 + 4 - length, seqId
@@ -92,7 +92,7 @@ class Execute {
       length += 1; // new-params-bound-flag
       length += 2 * this.parameters.length; // type byte for each parameter if new-params-bound-flag is set
       parameters = this.parameters.map(value =>
-        toParameter(value, self.encoding)
+        toParameter(value, this.encoding)
       );
       length += parameters.reduce(
         (accumulator, parameter) => accumulator + parameter.length,

lib/packets/handshake.js

@@ -15,14 +15,13 @@ class Handshake {
   }
 
   setScrambleData(cb) {
-    const self = this;
     require('crypto').randomBytes(20, (err, data) => {
       if (err) {
         cb(err);
         return;
       }
-      self.authPluginData1 = data.slice(0, 8);
-      self.authPluginData2 = data.slice(8, 20);
+      this.authPluginData1 = data.slice(0, 8);
+      this.authPluginData2 = data.slice(8, 20);
       cb();
     });
   }

lib/pool_cluster.js

@@ -8,23 +8,15 @@ const EventEmitter = require('events').EventEmitter;
  * Selector
  */
 const makeSelector = {
-  RR: () => {
+  RR() {
     let index = 0;
-    return clusterIds => {
-      if (index >= clusterIds.length) {
-        index = 0;
-      }
-
-      const clusterId = clusterIds[index++];
-
-      return clusterId;
-    };
+    return clusterIds => clusterIds[index++ % clusterIds.length];
   },
-  RANDOM: () => {
+  RANDOM() {
     return clusterIds =>
       clusterIds[Math.floor(Math.random() * clusterIds.length)];
   },
-  ORDER: () => {
+  ORDER() {
     return clusterIds => clusterIds[0];
   }
 };
@@ -182,20 +174,20 @@ class PoolCluster extends EventEmitter {
   }
 
   _getConnection(node, cb) {
-    const self = this;
-    node.pool.getConnection(function(err, connection) {
+    node.pool.getConnection((err, connection) => {
       if (err) {
-        self._increaseErrorCount(node);
-        if (self._canRetry) {
-          self.emit('warn', err);
+        this._increaseErrorCount(node);
+        if (this._canRetry) {
+          // REVIEW: this seems wrong?
+          this.emit('warn', err);
           // eslint-disable-next-line no-console
           console.warn('[Error] PoolCluster : ' + err);
           return cb(null, 'retry');
         } else {
           return cb(err);
         }
       } else {
-        self._decreaseErrorCount(node);
+        this._decreaseErrorCount(node);
       }
       connection._clusterId = node.id;
       return cb(null, connection);

lib/pool_connection.js

@@ -9,10 +9,11 @@ class PoolConnection extends Connection {
     // When a fatal error occurs the connection's protocol ends, which will cause
     // the connection to end as well, thus we only need to watch for the end event
     // and we will be notified of disconnects.
-    this.on('end', function() {
+    // REVIEW: Moved to `once`
+    this.once('end', () => {
       this._removeFromPool();
     });
-    this.on('error', function() {
+    this.once('error', () => {
       this._removeFromPool();
     });
   }
@@ -44,7 +45,7 @@ class PoolConnection extends Connection {
 
   destroy() {
     this._removeFromPool();
-    return Connection.prototype.destroy.apply(this, arguments);
+    super.destroy();
   }
 
   _removeFromPool() {

package.json

@@ -45,14 +45,14 @@
   "author": "Andrey Sidorov <sidorares@yandex.ru>",
   "license": "MIT",
   "dependencies": {
-    "denque": "1.4.0",
+    "denque": "^1.4.0",
     "generate-function": "^2.3.1",
     "iconv-lite": "^0.4.24",
     "long": "^4.0.0",
-    "lru-cache": "4.1.3",
-    "named-placeholders": "1.1.1",
-    "seq-queue": "0.0.5",
-    "sqlstring": "2.3.1"
+    "lru-cache": "^4.1.3",
+    "named-placeholders": "^1.1.2",
+    "seq-queue": "^0.0.5",
+    "sqlstring": "^2.3.1"
   },
   "devDependencies": {
     "assert-diff": "^2.0.2",

test/common.js

@@ -25,15 +25,23 @@ module.exports.SqlString = require('sqlstring');
 module.exports.config = config;
 
 module.exports.waitDatabaseReady = function(callback) {
+  const start = Date.now();
   const tryConnect = function() {
     const conn = module.exports.createConnection();
-    conn.on('error', err => {
-      console.log(err);
+    conn.once('error', err => {
+      if (err.code !== 'PROTOCOL_CONNECTION_LOST' && err.code !== 'ETIMEDOUT') {
+        console.log('Unexpected error waiting for connection', err);
+      }
+      try {
+        conn.close();
+      } catch (err) {
+        // ignore
+      }
       console.log('not ready');
       setTimeout(tryConnect, 1000);
     });
-    conn.on('connect', () => {
-      console.log('ready!');
+    conn.once('connect', () => {
+      console.log(`ready after ${Date.now() - start}ms!`);
       conn.close();
       callback();
     });

test/integration/promise-wrappers/test-promise-wrappers.js

@@ -145,6 +145,7 @@ function testEventsConnect() {
         );
       }
 
+      /* eslint-disable no-invalid-this */
       conn
         .once('error', function() {
           assert.equal(this, conn);
@@ -168,6 +169,7 @@ function testEventsConnect() {
 
           doneEventsConnect = events === 5;
         });
+      /* eslint-enable no-invalid-this */
 
       conn.connection.emit('error', new Error());
       conn.connection.emit('drain');
@@ -295,6 +297,7 @@ function testEventsPool() {
     );
   }
 
+  /* eslint-disable no-invalid-this */
   pool
     .once('acquire', function() {
       assert.equal(this, pool);
@@ -314,6 +317,7 @@ function testEventsPool() {
 
       doneEventsPool = events === 4;
     });
+  /* eslint-enable no-invalid-this */
 
   pool.pool.emit('acquire');
   pool.pool.emit('connection');

test/integration/test-namedPlaceholders.js

@@ -12,7 +12,7 @@ test('Test namedPlaceholder as command parameter', {
   'Enabled in connection config, disabled in query command': () => {
     // enabled in initial config, disable in test
     const c = createConnection({ namedPlaceholders: true });
-    c.query({ sql: query, namedPlaceholders: false }, values, function(err) {
+    c.query({ sql: query, namedPlaceholders: false }, values, err => {
       if (!err || !err.sqlMessage.match(/right syntax to use near ':named'/)) {
         assert.fail(
           'Expected err.sqlMessage to contain "right syntax to use near \':named\'" sqlMessage: ' +
@@ -24,21 +24,15 @@ test('Test namedPlaceholder as command parameter', {
   },
   'Disabled in connection config, enable query command': () => {
     const c = createConnection({ namedPlaceholders: false });
-    c.query({ sql: query, namedPlaceholders: true }, values, function(
-      err,
-      rows
-    ) {
+    c.query({ sql: query, namedPlaceholders: true }, values, (err, rows) => {
       assert.ifError(err);
       assert.equal(rows[0].result, 1);
       c.end();
     });
   },
   'Disabled in connection config, enable execute command': () => {
     const c = createConnection({ namedPlaceholders: false });
-    c.execute({ sql: query, namedPlaceholders: true }, values, function(
-      err,
-      rows
-    ) {
+    c.execute({ sql: query, namedPlaceholders: true }, values, (err, rows) => {
       assert.ifError(err);
       assert.equal(rows[0].result, 1);
       c.end();