Question

Is there any way to define different mock-expects for different input arguments? For example, I have database layer class called DB. This class has method called Query(string $query), that method takes an SQL query string on input. Can I create mock for this class (DB) and set different return values for different Query method calls that depends on input query string?

Answer 1

The PHPUnit Mocking library (by default) determines whether an expectation matches based solely on the matcher passed to expects parameter and the constraint passed to method. Because of this, two expect calls that only differ in the arguments passed to with will fail because both will match but only one will verify as having the expected behavior. See the reproduction case after the actual working example.

---

For you problem you need to use ->at() or ->will($this->returnCallback( as outlined in another question on the subject.

Example:

<?php

class DB {
    public function Query($sSql) {
        return "";
    }
}

class fooTest extends PHPUnit_Framework_TestCase {


    public function testMock() {

        $mock = $this->getMock('DB', array('Query'));

        $mock
            ->expects($this->exactly(2))
            ->method('Query')
            ->with($this->logicalOr(
                 $this->equalTo('select * from roles'),
                 $this->equalTo('select * from users')
             ))
            ->will($this->returnCallback(array($this, 'myCallback')));

        var_dump($mock->Query("select * from users"));
        var_dump($mock->Query("select * from roles"));
    }

    public function myCallback($foo) {
        return "Called back: $foo";
    }
}

Reproduces:

phpunit foo.php
PHPUnit 3.5.13 by Sebastian Bergmann.

string(32) "Called back: select * from users"
string(32) "Called back: select * from roles"
.

Time: 0 seconds, Memory: 4.25Mb

OK (1 test, 1 assertion)

---

---

Reproduce why two ->with() calls don’t work:

<?php

class DB {
    public function Query($sSql) {
        return "";
    }
}

class fooTest extends PHPUnit_Framework_TestCase {


    public function testMock() {

        $mock = $this->getMock('DB', array('Query'));
        $mock
            ->expects($this->once())
            ->method('Query')
            ->with($this->equalTo('select * from users'))
            ->will($this->returnValue(array('fred', 'wilma', 'barney')));

        $mock
            ->expects($this->once())
            ->method('Query')
            ->with($this->equalTo('select * from roles'))
            ->will($this->returnValue(array('admin', 'user')));

        var_dump($mock->Query("select * from users"));
        var_dump($mock->Query("select * from roles"));
    }

}

Results in

 phpunit foo.php
PHPUnit 3.5.13 by Sebastian Bergmann.

F

Time: 0 seconds, Memory: 4.25Mb

There was 1 failure:

1) fooTest::testMock
Failed asserting that two strings are equal.
--- Expected
+++ Actual
@@ @@
-select * from roles
+select * from users

/home/.../foo.php:27

FAILURES!
Tests: 1, Assertions: 0, Failures: 1