obsolete: make _computeobsoleteset much faster This patch makes _computeobsoleteset much faster by looping over the draft and secrets as opposed to looping over the successors. This works because "number of draft and secret" is typically way smaller(<100) than the number of successor in the repo (~90k in my checkout of core mercurial as of today). And also because it is very fast to compute "not public()". I timed the code with the following setup: """ from mercurial import hg, ui, obsolete ui = ui.ui() repo = hg.repository(ui, "~/hg") l = repo.obsstore.successors # This caches the result """ With about 90k successors. k=obsolete._computeobsoleteset(repo) before this patch: 10 loops, best of 3: 33.9 ms per loop k=obsolete._computeobsoleteset(repo) after this patch: 10000 loops, best of 3: 83.3 µs per loop