Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> writes: >> > No. Here's a simple example: >> > >> > Y >> > / >> > / >> > X--B >> > >> > In this diagram, X = B^. But B isn't reachable from either X or Y, >> > whereas it is reachable from one of X's children (namely Y). > ... > Thus, if B introduced a bug, that bug would not be present in Y. But Y > might be better for testing than X, because Y might fix some other > problems that are present in X. The problem with that line of reasoning is that in real life there will be unbound number of Y's that forked from a point before somebody wrote B. Which one among these Y's would you pick and why? If Y has fixed another problem that is present in X and make it easier to test, Z, a direct descendant of Y (i.e. Z^1 = Y), may have fixed yet another problem that is unrelated to the problem B introduced and it may make the result even easier to test. Where do you stop? Still confused... -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html