How to output in CLI during execution of PHP Unit tests?

Question

UPDATE

Just realized another way to do this that works much better than the --verbose command line option:

class TestSomething extends PHPUnit_Framework_TestCase {
    function testSomething() {
        $myDebugVar = array(1, 2, 3);
        fwrite(STDERR, print_r($myDebugVar, TRUE));
    }
}

This lets you dump anything to your console at any time without all the unwanted output that comes along with the --verbose CLI option.

---

As other answers have noted, it's best to test output using the built-in methods like:

$this->expectOutputString('foo');

However, sometimes it's helpful to be naughty and see one-off/temporary debugging output from within your test cases. There is no need for the var_dump hack/workaround, though. This can easily be accomplished by setting the --verbose command line option when running your test suite. For example:

$ phpunit --verbose -c phpunit.xml

This will display output from inside your test methods when running in the CLI environment.

See: Writing Tests for PHPUnit - Testing Output.

Update: See rdlowrey's update below regarding the use of fwrite(STDERR, print_r($myDebugVar, TRUE)); as a much simpler work around

---

This behaviour is intentional (as jasonbar has pointed out). The conflicting state of the manual has been reported to PHPUnit.

A work-around is to have PHPUnit assert the expected output is empty (when infact there is output) which will trigger the unexpected output to be shown.

class theTest extends PHPUnit_Framework_TestCase
{
    /**
     * @outputBuffering disabled
     */
    public function testOutput() {
        $this->expectOutputString(''); // tell PHPUnit to expect '' as output
        print_r("Hello World");
        print "Ping";
        echo "Pong";
        $out = "Foo";
        var_dump($out);
    }   
}

gives:

PHPUnit @package_version@ by Sebastian Bergmann.

F

Time: 1 second, Memory: 3.50Mb

There was 1 failure:

1) theTest::testOutput
Failed asserting that two strings are equal.
--- Expected
+++ Actual
@@ @@
-''
+'Hello WorldPingPongstring(4) "Foo"
+'

FAILURES!
Tests: 1, Assertions: 1, Failures: 1.

Be certain to disable any other assertions you have for the test as they may fail before the output assertion is tested (and hence you wont see the output).

Try using --debug

Useful if you're trying to get the right path to an include or source data file.

It's not a bug, but very much intentional. Your best bet is to write to a log file of some kind and tail the log to watch for output.

If you are trying to TEST output, check this out.

Also:

Note: Please note that PHPUnit swallows all output that is emitted during the execution of a test. In strict mode, a test that emits output will fail.