Improve error message to show last error family first

Author: clue

src/HappyEyeBallsConnectionBuilder.php

@@ -49,6 +49,7 @@ final class HappyEyeBallsConnectionBuilder
     public $resolve;
     public $reject;
 
+    public $lastErrorFamily;
     public $lastError6;
     public $lastError4;
 
@@ -128,8 +129,10 @@ public function resolve($type, $reject)
 
             if ($type === Message::TYPE_A) {
                 $that->lastError4 = $e->getMessage();
+                $that->lastErrorFamily = 4;
             } else {
                 $that->lastError6 = $e->getMessage();
+                $that->lastErrorFamily = 6;
             }
 
             // cancel next attempt timer when there are no more IPs to connect to anymore
@@ -139,7 +142,7 @@ public function resolve($type, $reject)
             }
 
             if ($that->hasBeenResolved() && $that->ipsCount === 0) {
-                $reject($that->error());
+                $reject(new \RuntimeException($that->error()));
             }
 
             throw $e;
@@ -172,8 +175,10 @@ public function check($resolve, $reject)
 
             if (\strpos($ip, ':') === false) {
                 $that->lastError4 = $e->getMessage();
+                $that->lastErrorFamily = 4;
             } else {
                 $that->lastError6 = $e->getMessage();
+                $that->lastErrorFamily = 6;
             }
 
             // start next connection attempt immediately on error
@@ -193,7 +198,7 @@ public function check($resolve, $reject)
             if ($that->ipsCount === $that->failureCount) {
                 $that->cleanUp();
 
-                $reject($that->error());
+                $reject(new \RuntimeException($that->error()));
             }
         });
 
@@ -326,14 +331,16 @@ public function mixIpsIntoConnectQueue(array $ips)
 
     /**
      * @internal
-     * @return \RuntimeException
+     * @return string
      */
     public function error()
     {
         if ($this->lastError4 === $this->lastError6) {
             $message = $this->lastError6;
+        } elseif ($this->lastErrorFamily === 6) {
+            $message = 'Last error for IPv6: ' . $this->lastError6 . '. Previous error for IPv4: ' . $this->lastError4;
         } else {
-            $message = 'Last error for IPv6: ' . $this->lastError6 . '. Last error for IPv4: ' . $this->lastError4;
+            $message = 'Last error for IPv4: ' . $this->lastError4 . '. Previous error for IPv6: ' . $this->lastError6;
         }
 
         if ($this->hasBeenResolved() && $this->ipsCount === 0) {
@@ -346,6 +353,6 @@ public function error()
             $message = ': ' . $message;
         }
 
-        return new \RuntimeException('Connection to ' . $this->uri . ' failed'  . $message);
+        return 'Connection to ' . $this->uri . ' failed'  . $message;
     }
 }

tests/HappyEyeBallsConnectionBuilderTest.php

@@ -73,12 +73,13 @@ public function testConnectWillRejectWhenBothDnsLookupsRejectWithDifferentMessag
         $connector = $this->getMockBuilder('React\Socket\ConnectorInterface')->getMock();
         $connector->expects($this->never())->method('connect');
 
+        $deferred = new Deferred();
         $resolver = $this->getMockBuilder('React\Dns\Resolver\ResolverInterface')->getMock();
         $resolver->expects($this->exactly(2))->method('resolveAll')->withConsecutive(
             array('reactphp.org', Message::TYPE_AAAA),
             array('reactphp.org', Message::TYPE_A)
         )->willReturnOnConsecutiveCalls(
-            \React\Promise\reject(new \RuntimeException('DNS6 error')),
+            $deferred->promise(),
             \React\Promise\reject(new \RuntimeException('DNS4 error'))
         );
 
@@ -89,14 +90,15 @@ public function testConnectWillRejectWhenBothDnsLookupsRejectWithDifferentMessag
         $builder = new HappyEyeBallsConnectionBuilder($loop, $connector, $resolver, $uri, $host, $parts);
 
         $promise = $builder->connect();
+        $deferred->reject(new \RuntimeException('DNS6 error'));
 
         $exception = null;
         $promise->then(null, function ($e) use (&$exception) {
             $exception = $e;
         });
 
         $this->assertInstanceOf('RuntimeException', $exception);
-        $this->assertEquals('Connection to tcp://reactphp.org:80 failed during DNS lookup. Last error for IPv6: DNS6 error. Last error for IPv4: DNS4 error', $exception->getMessage());
+        $this->assertEquals('Connection to tcp://reactphp.org:80 failed during DNS lookup. Last error for IPv6: DNS6 error. Previous error for IPv4: DNS4 error', $exception->getMessage());
     }
 
     public function testConnectWillStartDelayTimerWhenIpv4ResolvesAndIpv6IsPending()
@@ -433,7 +435,7 @@ public function testConnectWillRejectWhenOnlyTcp6ConnectionRejectsAndCancelNextA
         });
 
         $this->assertInstanceOf('RuntimeException', $exception);
-        $this->assertEquals('Connection to tcp://reactphp.org:80 failed: Last error for IPv6: Connection refused. Last error for IPv4: DNS failed', $exception->getMessage());
+        $this->assertEquals('Connection to tcp://reactphp.org:80 failed: Last error for IPv6: Connection refused. Previous error for IPv4: DNS failed', $exception->getMessage());
     }
 
     public function testConnectWillRejectWhenOnlyTcp4ConnectionRejectsAndWillNeverStartNextAttemptTimer()
@@ -469,7 +471,7 @@ public function testConnectWillRejectWhenOnlyTcp4ConnectionRejectsAndWillNeverSt
         });
 
         $this->assertInstanceOf('RuntimeException', $exception);
-        $this->assertEquals('Connection to tcp://reactphp.org:80 failed: Last error for IPv6: DNS failed. Last error for IPv4: Connection refused', $exception->getMessage());
+        $this->assertEquals('Connection to tcp://reactphp.org:80 failed: Last error for IPv4: Connection refused. Previous error for IPv6: DNS failed', $exception->getMessage());
     }
 
     public function testConnectWillRejectWhenAllConnectionsRejectAndCancelNextAttemptTimerImmediately()