On Sun, Jun 9, 2013 at 7:24 PM, Junio C Hamano <gits...@pobox.com> wrote: > The primary invariant of sort_in_topological_order() is that a > parent commit is not emitted untile all children of it are. When
s/untile/until/ > traversing a forked history like this with "git log C E": > > A----B----C > \ > D----E > > we ensure that A is emitted after all of B, C, D, and E are done, B > has to wait until C is done, and D has to wait until E is done. > > In some applications, however, we would further want to control how > these child commits B, C, D and E on two parallel ancestry chains > are shown. > > Most of the time, we would want to see C and B emitted together, and > then E and D, and finally A (i.e. the --topo-order output). The > "lifo" parameter of the sort_in_topological_order() function is used > to control this behaviour. We start the traversal by knowing two > commits, C and E. While keeping in mind that we also need to > inspect E later, we pick C first to inspect, and we notice and > record that B needs to be inspected. By structuring the "work to be > done" set as a LIFO stack, we ensure that B is inspected next, > before other in-flight commits we had known that we will need to > inspect, e.g. E. > > When showing in --date-order, we would want to see commits ordered > by timestamps, i.e. show C, E, B and D in this order before showing > A, possibly mixing commits from two parallel histories together. > When "lifo" parameter is set to false, the function keeps the "work > to be done" set sorted in the date order to realize this semantics. > After inspecting C, we add B to the "work to be done" set, but the > next commit we inspect from the set is E which is newer than B. > > The name "lifo", however, is too strongly tied to the way how the s/the way// > function implements its behaviour, and does not describe what the > behaviour _means_. > > Replace this field with an enum rev_sort_order, with two possible > values: REV_SORT_IN_GRAPH_ORDER and REV_SORT_BY_COMMIT_DATE, and > update the existing code. The mechanical replacement rule is: > > "lifo == 0" is equivalent to "sort_order == REV_SORT_BY_COMMIT_DATE" > "lifo == 1" is equivalent to "sort_order == REV_SORT_IN_GRAPH_ORDER" > > Signed-off-by: Junio C Hamano <gits...@pobox.com> -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
