revlog: optimize ancestors() to not check filtered revisions for each While reviewing the Rust implementation, I noticed iter(ancestors) doesn't need to check filtering state for each parent revision. And doing that appears to have some measurable perf win. $ hg perfancestors -R mercurial (orig) wall 0.038093 comb 0.040000 user 0.040000 sys 0.000000 (best of 100) (this) wall 0.024795 comb 0.020000 user 0.020000 sys 0.000000 (best of 117)