def test_source_changes_cause_rebuild(self):
        '''
        Test that changes to sources and headers cause rebuilds, but not
        changes to unused files (as determined by the dependency file) in the
        input files list.
        '''
        testdir = os.path.join(self.common_test_dir, '19 header in file list')
        self.init(testdir)
        self.build()
        # Immediately rebuilding should not do anything
        self.assertBuildIsNoop()
        # Changing mtime of header.h should rebuild everything
        self.utime(os.path.join(testdir, 'header.h'))
        self.assertBuildRelinkedOnlyTarget('prog')

        Test that changes to sources and headers cause rebuilds, but not
        changes to unused files (as determined by the dependency file) in the
        input files list.
        
unittests/allplatformstests.py