not using async

sindresorhus · Mar 25, 2019 · a9154ed · a9154ed
1 parent e711e66
commit a9154ed
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Showing 2 changed files with 36 additions and 25 deletions.
diff --git a/index.js b/index.js
@@ -13,24 +13,35 @@ const getAvailablePort = options => new Promise((resolve, reject) => {
 	});
 });
 
-module.exports = async options => {
-	if (options && options.port) {
-		const ports = (typeof options.port === 'number') ? [options.port] : options.port;
-
-		for (const port of ports) {
-			const gotPort = await getAvailablePort(Object.assign({}, options, {port})); // eslint-disable-line no-await-in-loop
-			if (gotPort !== null) {
-				return gotPort;
+module.exports = options => {
+	const ports = (options && options.port) ?
+		(typeof options.port === 'number') ? [options.port] : options.port :
+		[];
+
+	const iterator = ports[Symbol.iterator]();
+	let zeroNotTried = true;
+
+	const tryNext = () => {
+		let {value: port, done} = iterator.next();
+		if (done) {
+			if (zeroNotTried) {
+				zeroNotTried = false;
+				port = 0;
+			} else {
+				return Promise.reject(new Error('no available ports found'));
 			}
 		}
-	}
 
-	const gotPort = await getAvailablePort(Object.assign({}, options, {port: 0}));
-	if (gotPort === null) {
-		throw new Error('no available ports found');
-	}
+		return getAvailablePort(Object.assign({}, options, {port})).then(gotPort => {
+			if (gotPort === null) {
+				return tryNext();
+			}
+
+			return gotPort;
+		});
+	};
 
-	return gotPort;
+	return tryNext();
 };
 
 class PortRangeIterator {

diff --git a/test.js b/test.js
@@ -3,7 +3,7 @@ import test from 'ava';
 import pify from 'pify';
 import getPort from '.';
 
-test('port can be bound when promise resolves', async t => {
+test.serial('port can be bound when promise resolves', async t => {
 	const port = await getPort();
 	t.is(typeof port, 'number');
 	t.true(port > 0);
@@ -14,14 +14,14 @@ test('port can be bound when promise resolves', async t => {
 	t.is(server.address().port, port);
 });
 
-test('preferred port', async t => {
+test.serial('preferred port', async t => {
 	const desiredPort = 8080;
 	const port = await getPort({port: desiredPort});
 
 	t.is(port, desiredPort);
 });
 
-test('preferred port unavailable', async t => {
+test.serial('preferred port unavailable', async t => {
 	const desiredPort = 8282;
 	const server = net.createServer();
 	await pify(server.listen.bind(server))(desiredPort);
@@ -32,7 +32,7 @@ test('preferred port unavailable', async t => {
 	t.not(port, desiredPort);
 });
 
-test('port can be bound to IPv4 host when promise resolves', async t => {
+test.serial('port can be bound to IPv4 host when promise resolves', async t => {
 	const port = await getPort({host: '0.0.0.0'});
 	t.is(typeof port, 'number');
 	t.true(port > 0);
@@ -43,7 +43,7 @@ test('port can be bound to IPv4 host when promise resolves', async t => {
 	t.is(server.address().port, port);
 });
 
-test('preferred port given IPv4 host', async t => {
+test.serial('preferred port given IPv4 host', async t => {
 	const desiredPort = 8080;
 	const port = await getPort({
 		port: desiredPort,
@@ -53,7 +53,7 @@ test('preferred port given IPv4 host', async t => {
 	t.is(port, desiredPort);
 });
 
-test('preferred ports', async t => {
+test.serial('preferred ports', async t => {
 	const desiredPorts = [9910, 9912, 9913];
 	const port = await getPort({
 		port: desiredPorts,
@@ -63,7 +63,7 @@ test('preferred ports', async t => {
 	t.is(port, desiredPorts[0]);
 });
 
-test('first port in preferred ports array is unavailable', async t => {
+test.serial('first port in preferred ports array is unavailable', async t => {
 	const desiredPorts = [9090, 9091];
 
 	const server = net.createServer();
@@ -76,7 +76,7 @@ test('first port in preferred ports array is unavailable', async t => {
 	t.is(port, desiredPorts[1]);
 });
 
-test('all preferred ports in array are unavailable', async t => {
+test.serial('all preferred ports in array are unavailable', async t => {
 	const desiredPorts = [9990, 9991];
 
 	const server1 = net.createServer();
@@ -94,7 +94,7 @@ test('all preferred ports in array are unavailable', async t => {
 	t.not(port, desiredPorts[1]);
 });
 
-test('non-array iterables work', async t => {
+test.serial('non-array iterables work', async t => {
 	const desiredPorts = (function * () {
 		yield 9920;
 	})();
@@ -106,14 +106,14 @@ test('non-array iterables work', async t => {
 	t.is(port, 9920);
 });
 
-test('makeRange throws on invalid ranges', t => {
+test.serial('makeRange throws on invalid ranges', t => {
 	t.throws(() => getPort.makeRange(0, 0));
 	t.throws(() => getPort.makeRange(1023, 1023));
 	t.throws(() => getPort.makeRange(65536, 65536));
 	t.throws(() => getPort.makeRange(1025, 1024));
 });
 
-test('makeRange produces valid ranges', t => {
+test.serial('makeRange produces valid ranges', t => {
 	t.deepEqual([...getPort.makeRange(1024, 1025)], [1024]);
 	t.deepEqual([...getPort.makeRange(1024, 1027)], [1024, 1025, 1026]);
 });