function test_replace_resource_all_components()
 {
     $g = new SimpleGraph();
     $g->add_resource_triple('http://example.org/subj', 'http://example.org/subj', 'http://example.org/subj');
     $g->replace_resource('http://example.org/subj', 'http://example.org/other');
     $this->assertTrue($g->has_resource_triple('http://example.org/other', 'http://example.org/other', 'http://example.org/other'));
     $this->assertFalse($g->has_resource_triple('http://example.org/subj', 'http://example.org/subj', 'http://example.org/subj'));
 }