From 6dd3946a7e7433a1712199cec6243fe9366504b7 Mon Sep 17 00:00:00 2001
From: Bernhard Schussek <bschussek@gmail.com>
Date: Tue, 5 Aug 2014 11:52:34 +0200
Subject: [PATCH] [Process] Added process synchronization to the incremental
 output tests

The tests currently fail from time to time if the executing machine is under
heavy load. This leads to false negatives on Travis CI.

A side effect of the change is that the tests are much faster now.
---
 .../Process/Tests/AbstractProcessTest.php     | 34 +++++++++++++++----
 1 file changed, 27 insertions(+), 7 deletions(-)

diff --git a/src/Symfony/Component/Process/Tests/AbstractProcessTest.php b/src/Symfony/Component/Process/Tests/AbstractProcessTest.php
index 25de48eb1407..779fb5cca0bb 100644
--- a/src/Symfony/Component/Process/Tests/AbstractProcessTest.php
+++ b/src/Symfony/Component/Process/Tests/AbstractProcessTest.php
@@ -259,18 +259,28 @@ public function testGetErrorOutput()
 
     public function testGetIncrementalErrorOutput()
     {
-        $p = $this->getProcess(sprintf('php -r %s', escapeshellarg('$n = 0; while ($n < 3) { usleep(100000); file_put_contents(\'php://stderr\', \'ERROR\'); $n++; }')));
+        // use a lock file to toggle between writing ("W") and reading ("R") the
+        // error stream
+        $lock = tempnam(sys_get_temp_dir(), get_class($this).'Lock');
+        file_put_contents($lock, 'W');
+
+        $p = $this->getProcess(sprintf('php -r %s', escapeshellarg('$n = 0; while ($n < 3) { if (\'W\' === file_get_contents('.var_export($lock, true).')) { file_put_contents(\'php://stderr\', \'ERROR\'); $n++; file_put_contents('.var_export($lock, true).', \'R\'); } usleep(100); }')));
 
         $p->start();
         while ($p->isRunning()) {
-            $this->assertLessThanOrEqual(1, preg_match_all('/ERROR/', $p->getIncrementalErrorOutput(), $matches));
-            usleep(20000);
+            if ('R' === file_get_contents($lock)) {
+                $this->assertLessThanOrEqual(1, preg_match_all('/ERROR/', $p->getIncrementalErrorOutput(), $matches));
+                file_put_contents($lock, 'W');
+            }
+            usleep(100);
         }
+
+        unlink($lock);
     }
 
     public function testGetOutput()
     {
-        $p = $this->getProcess(sprintf('php -r %s', escapeshellarg('$n=0;while ($n<3) {echo \' foo \';$n++; usleep(500); }')));
+        $p = $this->getProcess(sprintf('php -r %s', escapeshellarg('$n = 0; while ($n < 3) { echo \' foo \'; $n++; }')));
 
         $p->run();
         $this->assertEquals(3, preg_match_all('/foo/', $p->getOutput(), $matches));
@@ -278,13 +288,23 @@ public function testGetOutput()
 
     public function testGetIncrementalOutput()
     {
-        $p = $this->getProcess(sprintf('php -r %s', escapeshellarg('$n=0;while ($n<3) { echo \' foo \'; usleep(50000); $n++; }')));
+        // use a lock file to toggle between writing ("W") and reading ("R") the
+        // output stream
+        $lock = tempnam(sys_get_temp_dir(), get_class($this).'Lock');
+        file_put_contents($lock, 'W');
+
+        $p = $this->getProcess(sprintf('php -r %s', escapeshellarg('$n = 0; while ($n < 3) { if (\'W\' === file_get_contents('.var_export($lock, true).')) { echo \' foo \'; $n++; file_put_contents('.var_export($lock, true).', \'R\'); } usleep(100); }')));
 
         $p->start();
         while ($p->isRunning()) {
-            $this->assertLessThanOrEqual(1, preg_match_all('/foo/', $p->getIncrementalOutput(), $matches));
-            usleep(20000);
+            if ('R' === file_get_contents($lock)) {
+                $this->assertLessThanOrEqual(1, preg_match_all('/foo/', $p->getIncrementalOutput(), $matches));
+                file_put_contents($lock, 'W');
+            }
+            usleep(100);
         }
+
+        unlink($lock);
     }
 
     public function testZeroAsOutput()