1 files changed, 43 insertions, 0 deletions
diff --git a/tests/phpunit/includes/libs/SamplingStatsdClientTest.php b/tests/phpunit/includes/libs/SamplingStatsdClientTest.php
new file mode 100644
index 00000000..be6732d5
--- /dev/null
+++ b/tests/phpunit/includes/libs/SamplingStatsdClientTest.php
@@ -0,0 +1,43 @@
+<?php
+
+use Liuggio\StatsdClient\Entity\StatsdData;
+
+class SamplingStatsdClientTest extends PHPUnit_Framework_TestCase {
+	/**
+	 * @dataProvider samplingDataProvider
+	 */
+	public function testSampling( $data, $sampleRate, $seed, $expectWrite ) {
+		$sender = $this->getMock( 'Liuggio\StatsdClient\Sender\SenderInterface' );
+		$sender->expects( $this->any() )->method( 'open' )->will( $this->returnValue( true ) );
+		if ( $expectWrite ) {
+			$sender->expects( $this->once() )->method( 'write' )
+				->with( $this->anything(), $this->equalTo( $data ) );
+		} else {
+			$sender->expects( $this->never() )->method( 'write' );
+		}
+		mt_srand( $seed );
+		$client = new SamplingStatsdClient( $sender );
+		$client->send( $data, $sampleRate );
+	}
+
+	public function samplingDataProvider() {
+		$unsampled = new StatsdData();
+		$unsampled->setKey( 'foo' );
+		$unsampled->setValue( 1 );
+
+		$sampled = new StatsdData();
+		$sampled->setKey( 'foo' );
+		$sampled->setValue( 1 );
+		$sampled->setSampleRate( '0.1' );
+
+		return array(
+			// $data, $sampleRate, $seed, $expectWrite
+			array( $unsampled, 1, 0 /*0.44*/, $unsampled ),
+			array( $sampled, 1, 0 /*0.44*/, null ),
+			array( $sampled, 1, 4 /*0.03*/, $sampled ),
+			array( $unsampled, 0.1, 4 /*0.03*/, $sampled ),
+			array( $sampled, 0.5, 0 /*0.44*/, null ),
+			array( $sampled, 0.5, 4 /*0.03*/, $sampled ),
+		);
+	}
+}