Given an image style and a wrapper, generate an image.
function createSampleImage($style, $wrapper) {
static $file;
if (!isset($file)) {
$files = $this
->drupalGetTestFiles('image');
$file = reset($files);
}
// Make sure we have an image in our wrapper testing file directory.
$source_uri = file_unmanaged_copy($file->uri, $wrapper . '://');
// Build the derivative image.
$derivative_uri = image_style_path($style
->id(), $source_uri);
$derivative = image_style_create_derivative($style, $source_uri, $derivative_uri);
return $derivative ? $derivative_uri : FALSE;
}