From: Micha Nelissen Date: Mon, 04 Mar 2019 09:13:23 GMT Subject: Re: [PATCH 1/1] Add feature to show log as a tree Message-ID: In-Reply-To: On 03-03-2019 14:16, Junio C Hamano wrote: > I am not sure what you mean by a "tree". It definitely is not a > tree perceived by Git users (which is what represents a directory > structure), and abusing the established term is confusing. I called it tree because the output looks like (right half) of a tree. I'm open to alternatives though. > There is no inherent ordering among children of a given commit, so > you'd invent some way to define what "the first child" is. That > much can be read from the above, but what is missing is why do you > even need to bother. What benefit do users get by identifying "the > first" child and cutting all others off---that is the necessary > justification for this change, which is missing from the above > explanation. Right, in my mind the problem statement is so clear and I didn't write it down. There should have been an introduction paragraph. Problem I want to solve. The --graph output is useful but often unreadable, due to the many parallel lines. On the other hand, with the default straight line log output all structure is lost. I am trying some middle ground to see merge structure, but keep history readable. I noticed in particular the branch point causes a line to go around or go in between many commits leading to clutter, so I want to remove these. By itself the exact point branched from is rarely important (at least to me). And if it is, then there still is --graph :-). > "A (depth) level" is poorly explained---in fact, it is not explained > what it means at all. "We designate the first child of each commit > by some magic" is all we can read from it. When processing the commit nodes. Start with depth level 0. Given some current depth level D, assign depth level D, D+1, ... D+N-1 to the N parents of a (merge) commit. Recurse. In the output, the depth level is more or less the column number the star '*' is in. (Although after merges of merges, there will be gaps in the level numbering.) > After explaining "some magic" in a more meaningful way, perhaps > you'd realize that you'd want to stop saying "first child". It OK well, the term "first parent" is already in the man page, right? --first-parent. So the first child of a commit is the commit C among all children H, such that when all of H are traced back to a common point S, the trace line from C is the one that ends being the first parent of S. > ignore all side branches and concentrate only on the trunk of a > tree). And I'd probably call each child that is on the "trunk" line > of the most important lineage "primary child" or something like > that. Sort of, but remember this works recursive, there can be merges of merges. Therefore the output is not a single trunk line. In other words, the above commit S doesn't need to be on the trunk (or, '*' completely left in the graph output). > In any case, if this is to sit next to and be friends with > "--topo-order", the option should be named as "--some-order". > The option name "--tree" (or "--blob", "--tag", or "--commit" for > that matter) is obviously unacceptable if the option is about > specifying how the commits in the "git log" output are ordered. I see it as alternative to the --graph option. I also made it jump there, but maybe gotos are rejected from style point of view. In this case I thought it would be clear to see it as alternative to --graph. It doesn't do justice in my opinion to call it --graph --micha-order (or whatever ;-)), as it is not only about changing the order of commit display. But again, I'm open to alternatives, I can make a personal alias anyway :-). > Having said that, if you are omitting commits that are not on the > primary lineage of the history, then this is not "--anything-order" > option, in which case it may want to sit next to and be friends with Ah no, it doesn't omit any commits. All commits are displayed. > Without clear explanation of what the change attempts to achieve in > docs and tests, there is no way to review to see if the new code is > correct. How can I add tests for this feature? I'm also open to what kinds of documentation to add, as I find it way easier to explain when you actually run it to see the output it generates, than from abstract paragraph of documentation text (like a manpage has). Some mathematical-type of explanation like above is also not really immediately enlightening, and also not necessary to use it I think. Thanks for review, Micha