assertFalse($transformer->isValid([])); $this->assertFalse($transformer->isValid(['content-type' => 'text/plain'])); $this->assertFalse($transformer->isValid(['content-type' => 'tExT/HtML'])); $this->assertTrue($transformer->isValid(['content-type' => 'text/html'])); $this->assertTrue($transformer->isValid(['content-TYPE' => 'text/html'])); $this->assertTrue($transformer->isValid(['content-TYPE' => 'text/plain, text/html; charset=utf-8'])); $this->assertTrue($transformer->transform()); $this->assertStringContainsString("Hello world", $transformer->getOutput()); $this->assertStringContainsString("Preview by", $transformer->getOutput()); } }