fix: hanging close promise (#140)

src/socket-to-conn.js

@@ -78,7 +78,10 @@ module.exports = (socket, options) => {
           resolve()
         }, CLOSE_TIMEOUT)
 
-        socket.once('close', () => clearTimeout(timeout))
+        socket.once('close', () => {
+          clearTimeout(timeout)
+          resolve()
+        })
         socket.end(err => {
           maConn.timeline.close = Date.now()
           if (err) return reject(err)

test/connection.spec.js

@@ -50,4 +50,36 @@ describe('valid localAddr and remoteAddr', () => {
     expect(dialerConn.remoteAddr.toString())
       .to.equal(listenerConn.localAddr.toString())
   })
+
+  it('should handle multiple simultaneous closes', async () => {
+    // Create a Promise that resolves when a connection is handled
+    let handled
+    const handlerPromise = new Promise(resolve => { handled = resolve })
+
+    const handler = conn => handled(conn)
+
+    // Create a listener with the handler
+    const listener = tcp.createListener(handler)
+
+    // Listen on the multi-address
+    await listener.listen(ma)
+
+    const localAddrs = listener.getAddrs()
+    expect(localAddrs.length).to.equal(1)
+
+    // Dial to that address
+    const dialerConn = await tcp.dial(localAddrs[0])
+
+    // Wait for the incoming dial to be handled
+    await handlerPromise
+
+    // Close the listener with two simultaneous calls to `close`
+    await Promise.race([
+      new Promise((resolve, reject) => setTimeout(() => reject(new Error('Timed out waiting for connection close')), 500)),
+      await Promise.all([
+        dialerConn.close(),
+        dialerConn.close()
+      ])
+    ])
+  })
 })