tools: enable no-else-return ESLint rule

.eslintrc.yaml

@@ -34,6 +34,7 @@ rules:
   # Best Practices
   # http://eslint.org/docs/rules/#best-practices
   dot-location: [2, property]
+  no-else-return: 2
   no-fallthrough: 2
   no-global-assign: 2
   no-multi-spaces: 2

benchmark/_http-benchmarkers.js

@@ -35,9 +35,8 @@ AutocannonBenchmarker.prototype.processResults = function(output) {
   }
   if (!result || !result.requests || !result.requests.average) {
     return undefined;
-  } else {
-    return result.requests.average;
   }
+  return result.requests.average;
 };
 
 function WrkBenchmarker() {
@@ -63,9 +62,8 @@ WrkBenchmarker.prototype.processResults = function(output) {
   const result = match && +match[1];
   if (!isFinite(result)) {
     return undefined;
-  } else {
-    return result;
   }
+  return result;
 };
 
 const http_benchmarkers = [new WrkBenchmarker(), new AutocannonBenchmarker()];

benchmark/scatter.js

@@ -33,9 +33,8 @@ let printHeader = true;
 function csvEncodeValue(value) {
   if (typeof value === 'number') {
     return value.toString();
-  } else {
-    return '"' + value.replace(/"/g, '""') + '"';
   }
+  return '"' + value.replace(/"/g, '""') + '"';
 }
 
 (function recursive(i) {

lib/_http_common.js

@@ -101,8 +101,7 @@ function parserOnHeadersComplete(versionMajor, versionMinor, headers, method,
 
   if (typeof skipBody !== 'number')
     return skipBody ? 1 : 0;
-  else
-    return skipBody;
+  return skipBody;
 }
 
 // XXX This is a mess.

lib/_stream_readable.js

@@ -18,18 +18,17 @@ function prependListener(emitter, event, fn) {
   // event emitter implementation with them.
   if (typeof emitter.prependListener === 'function') {
     return emitter.prependListener(event, fn);
-  } else {
-    // This is a hack to make sure that our error handler is attached before any
-    // userland ones.  NEVER DO THIS. This is here only because this code needs
-    // to continue to work with older versions of Node.js that do not include
-    // the prependListener() method. The goal is to eventually remove this hack.
-    if (!emitter._events || !emitter._events[event])
-      emitter.on(event, fn);
-    else if (Array.isArray(emitter._events[event]))
-      emitter._events[event].unshift(fn);
-    else
-      emitter._events[event] = [fn, emitter._events[event]];
   }
+  // This is a hack to make sure that our error handler is attached before any
+  // userland ones.  NEVER DO THIS. This is here only because this code needs
+  // to continue to work with older versions of Node.js that do not include
+  // the prependListener() method. The goal is to eventually remove this hack.
+  if (!emitter._events || !emitter._events[event])
+    emitter.on(event, fn);
+  else if (Array.isArray(emitter._events[event]))
+    emitter._events[event].unshift(fn);
+  else
+    emitter._events[event] = [fn, emitter._events[event]];
 }
 
 function ReadableState(options, stream) {
@@ -251,8 +250,7 @@ function howMuchToRead(n, state) {
     // Only flow one buffer at a time
     if (state.flowing && state.length)
       return state.buffer.head.data.length;
-    else
-      return state.length;
+    return state.length;
   }
   // If we're asking for more than the current hwm, then raise the hwm.
   if (n > state.highWaterMark)

lib/_tls_legacy.js

@@ -386,9 +386,8 @@ CryptoStream.prototype.isSessionReused = function() {
 CryptoStream.prototype.getCipher = function(err) {
   if (this.pair.ssl) {
     return this.pair.ssl.getCurrentCipher();
-  } else {
-    return null;
   }
+  return null;
 };
 
 
@@ -490,9 +489,8 @@ Object.defineProperty(CryptoStream.prototype, 'readyState', {
       return 'readOnly';
     } else if (!this.readable && this.writable) {
       return 'writeOnly';
-    } else {
-      return 'closed';
     }
+    return 'closed';
   }
 });
 
@@ -521,9 +519,8 @@ util.inherits(CleartextStream, CryptoStream);
 CleartextStream.prototype._internallyPendingBytes = function() {
   if (this.pair.ssl) {
     return this.pair.ssl.clearPending();
-  } else {
-    return 0;
   }
+  return 0;
 };
 
 
@@ -581,9 +578,8 @@ util.inherits(EncryptedStream, CryptoStream);
 EncryptedStream.prototype._internallyPendingBytes = function() {
   if (this.pair.ssl) {
     return this.pair.ssl.encPending();
-  } else {
-    return 0;
   }
+  return 0;
 };
 
 

lib/_tls_wrap.js

@@ -115,12 +115,11 @@ function requestOCSP(self, hello, ctx, cb) {
 
   if (self.server.listenerCount('OCSPRequest') === 0) {
     return cb(null);
-  } else {
-    self.server.emit('OCSPRequest',
-                     ctx.getCertificate(),
-                     ctx.getIssuer(),
-                     onOCSP);
   }
+  self.server.emit('OCSPRequest',
+                   ctx.getCertificate(),
+                   ctx.getIssuer(),
+                   onOCSP);
 
   var once = false;
   function onOCSP(err, response) {
@@ -655,9 +654,8 @@ TLSSocket.prototype.isSessionReused = function() {
 TLSSocket.prototype.getCipher = function(err) {
   if (this._handle) {
     return this._handle.getCurrentCipher();
-  } else {
-    return null;
   }
+  return null;
 };
 
 TLSSocket.prototype.getEphemeralKeyInfo = function() {
@@ -1090,9 +1088,8 @@ exports.connect = function(...args /* [port,] [host,] [options,] [cb] */) {
       if (options.rejectUnauthorized) {
         socket.destroy(verifyError);
         return;
-      } else {
-        socket.emit('secureConnect');
       }
+      socket.emit('secureConnect');
     } else {
       socket.authorized = true;
       socket.emit('secureConnect');

lib/assert.js

@@ -195,21 +195,20 @@ function _deepEqual(actual, expected, strict, memos) {
   // (although not necessarily the same order), equivalent values for every
   // corresponding key, and an identical 'prototype' property. Note: this
   // accounts for both named and indexed properties on Arrays.
-  } else {
-    memos = memos || {actual: [], expected: []};
+  }
+  memos = memos || {actual: [], expected: []};
 
-    const actualIndex = memos.actual.indexOf(actual);
-    if (actualIndex !== -1) {
-      if (actualIndex === memos.expected.indexOf(expected)) {
-        return true;
-      }
+  const actualIndex = memos.actual.indexOf(actual);
+  if (actualIndex !== -1) {
+    if (actualIndex === memos.expected.indexOf(expected)) {
+      return true;
     }
+  }
 
-    memos.actual.push(actual);
-    memos.expected.push(expected);
+  memos.actual.push(actual);
+  memos.expected.push(expected);
 
-    return objEquiv(actual, expected, strict, memos);
-  }
+  return objEquiv(actual, expected, strict, memos);
 }
 
 function isArguments(object) {

lib/buffer.js

@@ -191,9 +191,8 @@ function allocate(size) {
     poolOffset += size;
     alignPool();
     return b;
-  } else {
-    return createUnsafeBuffer(size);
   }
+  return createUnsafeBuffer(size);
 }
 
 
@@ -817,9 +816,8 @@ Buffer.prototype.toJSON = function() {
     for (var i = 0; i < this.length; ++i)
       data[i] = this[i];
     return { type: 'Buffer', data };
-  } else {
-    return { type: 'Buffer', data: [] };
   }
+  return { type: 'Buffer', data: [] };
 };
 
 
@@ -832,9 +830,8 @@ function adjustOffset(offset, length) {
   } else if (offset < 0) {
     offset += length;
     return offset > 0 ? offset : 0;
-  } else {
-    return offset < length ? offset : length;
   }
+  return offset < length ? offset : length;
 }
 
 

lib/dns.js

@@ -278,9 +278,8 @@ exports.resolve = function resolve(hostname, type_, callback_) {
 
   if (typeof resolver === 'function') {
     return resolver(hostname, callback);
-  } else {
-    throw new Error(`Unknown type "${type_}"`);
   }
+  throw new Error(`Unknown type "${type_}"`);
 };
 
 

lib/events.js

@@ -358,9 +358,8 @@ EventEmitter.prototype.removeListener =
           if (--this._eventsCount === 0) {
             this._events = new EventHandlers();
             return this;
-          } else {
-            delete events[type];
           }
+          delete events[type];
         } else if (position === 0) {
           list.shift();
         } else {
@@ -447,9 +446,8 @@ EventEmitter.prototype.listeners = function listeners(type) {
 EventEmitter.listenerCount = function(emitter, type) {
   if (typeof emitter.listenerCount === 'function') {
     return emitter.listenerCount(type);
-  } else {
-    return listenerCount.call(emitter, type);
   }
+  return listenerCount.call(emitter, type);
 };
 
 EventEmitter.prototype.listenerCount = listenerCount;

lib/fs.js

@@ -899,10 +899,9 @@ function preprocessSymlinkDestination(path, type, linkPath) {
     // A relative target is relative to the link's parent directory.
     path = pathModule.resolve(linkPath, '..', path);
     return pathModule._makeLong(path);
-  } else {
-    // Windows symlinks don't tolerate forward slashes.
-    return ('' + path).replace(/\//g, '\\');
   }
+  // Windows symlinks don't tolerate forward slashes.
+  return ('' + path).replace(/\//g, '\\');
 }
 
 fs.symlink = function(target, path, type_, callback_) {
@@ -1460,9 +1459,8 @@ function encodeRealpathResult(result, options) {
   const asBuffer = Buffer.from(result);
   if (options.encoding === 'buffer') {
     return asBuffer;
-  } else {
-    return asBuffer.toString(options.encoding);
   }
+  return asBuffer.toString(options.encoding);
 }
 
 fs.realpathSync = function realpathSync(p, options) {

lib/internal/url.js

@@ -699,9 +699,8 @@ class URLSearchParams {
       return `${this.constructor.name} {\n  ${output.join(',\n  ')} }`;
     } else if (output.length) {
       return `${this.constructor.name} { ${output.join(separator)} }`;
-    } else {
-      return `${this.constructor.name} {}`;
     }
+    return `${this.constructor.name} {}`;
   }
 }
 

lib/net.js

@@ -393,9 +393,8 @@ Object.defineProperty(Socket.prototype, 'readyState', {
       return 'readOnly';
     } else if (!this.readable && this.writable) {
       return 'writeOnly';
-    } else {
-      return 'closed';
     }
+    return 'closed';
   }
 });
 
@@ -1415,9 +1414,8 @@ Server.prototype.address = function() {
     return out;
   } else if (this._pipeName) {
     return this._pipeName;
-  } else {
-    return null;
   }
+  return null;
 };
 
 function onconnection(err, clientHandle) {