<?php

use OnlyBits\Connectors\WireAbstract;

class WireTest extends PHPUnit_Framework_TestCase
{
    public function testConnectionBetweenWires()
    {
        $wire1 = $this->getMockForAbstractClass('OnlyBits\Connectors\WireAbstract');
        $wire2 = $this->getMockForAbstractClass('OnlyBits\Connectors\WireAbstract');

        $wire1->expects($this->once())
             ->method('setValue')
             ->with($this->anything());

        $wire1->connect($wire2);
    }

    public function testWireIsReturned()
    {
        $wire1 = $this->getMockForAbstractClass('OnlyBits\Connectors\WireAbstract');
        $wire2 = $this->getMockForAbstractClass('OnlyBits\Connectors\WireAbstract');

        $wire = $wire1->connect($wire2);

        $this->assertInstanceOf('OnlyBits\Connectors\WireAbstract', $wire, "No instance of OnlyBits\Connectors\Wire was returned!");
    }
}

<?php

use OnlyBits\Connectors\WireAbstract;

class WireTest extends PHPUnit_Framework_TestCase
{
    public function testConnectionBetweenWires()
    {
        $wire1 = $this->getMockForAbstractClass('OnlyBits\Connectors\WireAbstract');
        $wire2 = $this->getMockForAbstractClass('OnlyBits\Connectors\WireAbstract');

        $wire1->expects($this->once())
             ->method('setValue')
             ->with($this->anything());

        $wire1->connect($wire2);
    }
}

Remove testWireIsReturned(). This test is no longer needed because the wire is no longer returned on connection.
Remove testWireIsReturned(). This test is no longer needed because the wire is no longer returned on connection.