Thanks - I think this is a useful guide to what can be a complicated topic. It looks good overall; I just have some minor comments below. > diff --git a/Documentation/Makefile b/Documentation/Makefile > index 76f2ecfc1b..91e5da67c4 100644 > --- a/Documentation/Makefile > +++ b/Documentation/Makefile > @@ -78,6 +78,7 @@ SP_ARTICLES += $(API_DOCS) > > TECH_DOCS += MyFirstContribution > TECH_DOCS += SubmittingPatches > +TECH_DOCS += MyFirstRevWalk Any reason why this is not in alphabetical order? > +Also add the relevant line in `builtin.h` near `cmd_whatchanged()`: > + > +---- > +extern int cmd_walken(int argc, const char **argv, const char *prefix); > +---- builtin.h no longer has "extern", so we can delete it. > +Add it to the `Makefile` near the line for `builtin\worktree.o`: > + > +---- > +BUILTIN_OBJS += builtin/walken.o > +---- In the first line, change the backslash to a slash. (The line in Makefile for "builtin/worktree.o" uses a forward slash as expected.) > +NOTE: For a more exhaustive overview of the new command process, take a look at > +`Documentation/MyFirstContribution.txt`. > + > +NOTE: A reference implementation can be found at TODO LINK. I think you have a reference implementation at https://github.com/nasamuffin/git/tree/revwalk? > +We'll start by enabling all types of objects in the `struct rev_info`. Unless > +you cloned or fetched your repository earlier with a filter, > +`exclude_promisor_objects` is unlikely to make a difference, but we'll turn it > +on just to make sure our lives are simple. We'll also turn on > +`tree_blobs_in_commit_order`, which means that we will walk a commit's tree and > +everything it points to immediately after we find each commit, as opposed to > +waiting for the end and walking through all trees after the commit history has > +been discovered. With the appropriate settings configured, we are ready to call > +`prepare_revision_walk()`. > + > +---- > +static void walken_object_walk(struct rev_info *rev) > +{ > + rev->tree_objects = 1; > + rev->blob_objects = 1; > + rev->tag_objects = 1; > + rev->tree_blobs_in_commit_order = 1; > + rev->exclude_promisor_objects = 1; Optional: I think we should not bother with exclude_promisor_objects. If the user really cloned with a filter, then every object would be a promisor object and the revision walk should output nothing, which is very confusing.
