Skip signal tests w/o PCNTL and skip timer tests on inaccurate platforms

The signal constants are only available when ext-pcntl is loaded. If it
is not loaded, simply skip all tests that reference these constants.

Before running a timer test and asserting its time interval, run a
simple test to check the accuracy on the current platform. This is known
to work on most common platforms, but will now avoid false negative test
results on platforms that are known to be slow (Travis CI and others).

Author: clue

phpunit.xml.dist

@@ -9,7 +9,7 @@
          processIsolation="false"
          stopOnFailure="false"
          syntaxCheck="false"
-         bootstrap="tests/bootstrap.php"
+         bootstrap="vendor/autoload.php"
 >
     <testsuites>
         <testsuite name="React Test Suite">

tests/AbstractLoopTest.php

@@ -491,10 +491,13 @@ function () {
 
     public function testRemoveSignalNotRegisteredIsNoOp()
     {
-        $this->loop->removeSignal(SIGINT, function () { });
+        $this->loop->removeSignal(2, function () { });
         $this->assertTrue(true);
     }
 
+    /**
+     * @requires extension pcntl
+     */
     public function testSignal()
     {
         if (!function_exists('posix_kill') || !function_exists('posix_getpid')) {
@@ -528,6 +531,9 @@ public function testSignal()
         $this->assertTrue($calledShouldNot);
     }
 
+    /**
+     * @requires extension pcntl
+     */
     public function testSignalMultipleUsagesForTheSameListener()
     {
         $funcCallCount = 0;
@@ -552,6 +558,9 @@ public function testSignalMultipleUsagesForTheSameListener()
         $this->assertSame(1, $funcCallCount);
     }
 
+    /**
+     * @requires extension pcntl
+     */
     public function testSignalsKeepTheLoopRunning()
     {
         $loop = $this->loop;
@@ -565,6 +574,9 @@ public function testSignalsKeepTheLoopRunning()
         $this->assertRunSlowerThan(1.5);
     }
 
+    /**
+     * @requires extension pcntl
+     */
     public function testSignalsKeepTheLoopRunningAndRemovingItStopsTheLoop()
     {
         $loop = $this->loop;

tests/SignalsHandlerTest.php

@@ -6,6 +6,9 @@
 
 final class SignalsHandlerTest extends TestCase
 {
+    /**
+     * @requires extension pcntl
+     */
     public function testEmittedEventsAndCallHandling()
     {
         $callCount = 0;

tests/StreamSelectLoopTest.php

@@ -49,13 +49,10 @@ public function signalProvider()
     /**
      * Test signal interrupt when no stream is attached to the loop
      * @dataProvider signalProvider
+     * @requires extension pcntl
      */
     public function testSignalInterruptNoStream($signal)
     {
-        if (!extension_loaded('pcntl')) {
-            $this->markTestSkipped('"pcntl" extension is required to run this test.');
-        }
-
         // dispatch signal handler every 10ms for 0.1s
         $check = $this->loop->addPeriodicTimer(0.01, function() {
             pcntl_signal_dispatch();
@@ -80,13 +77,10 @@ public function testSignalInterruptNoStream($signal)
     /**
      * Test signal interrupt when a stream is attached to the loop
      * @dataProvider signalProvider
+     * @requires extension pcntl
      */
     public function testSignalInterruptWithStream($signal)
     {
-        if (!extension_loaded('pcntl')) {
-            $this->markTestSkipped('"pcntl" extension is required to run this test.');
-        }
-
         // dispatch signal handler every 10ms
         $this->loop->addPeriodicTimer(0.01, function() {
             pcntl_signal_dispatch();

tests/Timer/AbstractTimerTest.php

@@ -22,8 +22,28 @@ public function testAddTimerReturnsNonPeriodicTimerInstance()
         $this->assertFalse($timer->isPeriodic());
     }
 
+    /**
+     * @depends testPlatformHasHighAccuracy
+     */
     public function testAddTimerWillBeInvokedOnceAndBlocksLoopWhenRunning()
     {
+        // Make no strict assumptions about actual time interval. Common
+        // environments usually provide millisecond accuracy (or better), but
+        // Travis and other CI systems are slow.
+        // We try to compensate for this by skipping accurate tests when the
+        // current platform is known to be inaccurate. We test this by sleeping
+        // 3x1ms and then measure the time for each iteration before running the
+        // actual test.
+        for ($i = 0; $i < 3; ++$i) {
+            $start = microtime(true);
+            usleep(1000);
+            $time = microtime(true) - $start;
+
+            if ($time < 0.001 || $time > 0.002) {
+                $this->markTestSkipped('Platform provides insufficient accuracy (' . $time . ' s)');
+            }
+        }
+
         $loop = $this->createLoop();
 
         $loop->addTimer(0.001, $this->expectCallableOnce());
@@ -32,10 +52,8 @@ public function testAddTimerWillBeInvokedOnceAndBlocksLoopWhenRunning()
         $loop->run();
         $end = microtime(true);
 
-        // make no strict assumptions about actual time interval.
-        // must be at least 0.001s (1ms) and should not take longer than 0.1s
         $this->assertGreaterThanOrEqual(0.001, $end - $start);
-        $this->assertLessThan(0.1, $end - $start);
+        $this->assertLessThan(0.002, $end - $start);
     }
 
     public function testAddPeriodicTimerReturnsPeriodicTimerInstance()