errorCollector.assertEquals("123", read(tf1));
tf2 = tr2.prepare(f2);
RepoUtils.modifyFileAppend(tf2, "B");
tr2.done(tf2);
errorCollector.assertEquals("AB", read(tf2));
File tf3 = tr2.prepare(f3);
errorCollector.assertTrue(tf3.exists());
RepoUtils.modifyFileAppend(tf3, "!");
tr2.done(tf3);
errorCollector.assertEquals("!", read(tf3));
tr2.rollback();