Test replacement when moving onto itself.
function testExistingReplaceSelf() {
// Setup a file to overwrite.
$contents = $this
->randomName(10);
$source = $this
->createFile(NULL, $contents);
// Copy the file over itself. Clone the object so we don't have to worry
// about the function changing our reference copy.
$result = file_move(clone $source, $source->uri, FILE_EXISTS_REPLACE);
$this
->assertFalse($result, t('File move failed.'));
$this
->assertEqual($contents, file_get_contents($source->uri), t('Contents of file were not altered.'));
// Check that no hooks were called while failing.
$this
->assertFileHooksCalled(array());
// Load the file from the database and make sure it is identical to what
// was returned.
$this
->assertFileUnchanged($source, file_load($source->fid, TRUE));
}