copies: simplify the handling of merges Instead of stacking copies for both parent on the head, we move copies outside of the heap into a dedicated dictionary. The two side of merge can we merged sooner, making the algorithm simpler. This simplicity reflect in the heap structure and speed up the execution for copies involving a large amount of merges. Here are timing for perfpathcopies of multiple revision pairs. - filelog: timing using filelog (with the introrev condition dropped) - base: this series base - before: the parent of this changeset - after: this changeset revision: large amount; added files: large amount; rename small amount; c3b14617fbd7 9ba6ab77fd29 filelog: ! wall 3.679613 comb 3.680000 user 3.580000 sys 0.100000 (median of 3) base: ! wall 8.884369 comb 8.880000 user 8.850000 sys 0.030000 (median of 3) before: ! wall 8.443747 comb 8.420000 user 8.410000 sys 0.010000 (median of 3) after: ! wall 4.697917 comb 4.690000 user 4.660000 sys 0.030000 (median of 3) revision: large amount; added files: small amount; rename small amount; c3b14617fbd7 f650a9b140d2 filelog: ! wall 0.003357 comb 0.010000 user 0.010000 sys 0.000000 (median of 781) base: ! wall 12.398524 comb 12.400000 user 12.330000 sys 0.070000 (median of 3) before: ! wall 10.852593 comb 10.850000 user 10.800000 sys 0.050000 (median of 3) after: ! wall 6.750832 comb 6.750000 user 6.640000 sys 0.110000 (median of 3) revision: large amount; added files: large amount; rename large amount; 08ea3258278e d9fa043f30c0 filelog: ! wall 2.754687 comb 2.760000 user 2.650000 sys 0.110000 (median of 4) base: ! wall 1.423166 comb 1.420000 user 1.400000 sys 0.020000 (median of 8) before: ! wall 1.068041 comb 1.060000 user 1.050000 sys 0.010000 (median of 10) after: ! wall 1.045916 comb 1.050000 user 1.040000 sys 0.010000 (median of 10) revision: small amount; added files: large amount; rename large amount; df6f7a526b60 a83dc6a2d56f filelog: ! wall 1.552293 comb 1.550000 user 1.510000 sys 0.040000 (median of 6 base: ! wall 0.022662 comb 0.020000 user 0.020000 sys 0.000000 (median of 128) before: ! wall 0.021111 comb 0.020000 user 0.020000 sys 0.000000 (median of 139) after: ! wall 0.021577 comb 0.020000 user 0.020000 sys 0.000000 (median of 138) revision: small amount; added files: large amount; rename small amount; 4aa4e1f8e19a 169138063d63 filelog: ! wall 1.500983 comb 1.500000 user 1.420000 sys 0.080000 (median of 7) base: ! wall 0.006956 comb 0.010000 user 0.010000 sys 0.000000 (median of 392) before: ! wall 0.004356 comb 0.010000 user 0.010000 sys 0.000000 (median of 675) after: ! wall 0.004329 comb 0.000000 user 0.000000 sys 0.000000 (median of 682) revision: small amount; added files: small amount; rename small amount; 4bc173b045a6 964879152e2e filelog: ! wall 0.011745 comb 0.020000 user 0.020000 sys 0.000000 (median of 250) base: ! wall 0.000156 comb 0.000000 user 0.000000 sys 0.000000 (median of 17180) before: ! wall 0.000100 comb 0.000000 user 0.000000 sys 0.000000 (median of 26912) after: ! wall 0.000105 comb 0.000000 user 0.000000 sys 0.000000 (median of 25689) revision: medium amount; added files: large amount; rename medium amount; c95f1ced15f2 2c68e87c3efe filelog: ! wall 3.228230 comb 3.230000 user 3.110000 sys 0.120000 (median of 4) base: ! wall 0.997640 comb 1.000000 user 0.980000 sys 0.020000 (median of 10) before: ! wall 0.778291 comb 0.780000 user 0.780000 sys 0.000000 (median of 13) after: ! wall 0.706594 comb 0.710000 user 0.710000 sys 0.000000 (median of 15) revision: medium amount; added files: medium amount; rename small amount; d343da0c55a8 d7746d32bf9d filelog: ! wall 1.052501 comb 1.060000 user 1.040000 sys 0.020000 (median of 10 base: ! wall 0.214519 comb 0.220000 user 0.220000 sys 0.000000 (median of 45) before: ! wall 0.160804 comb 0.160000 user 0.160000 sys 0.000000 (median of 62) after: ! wall 0.163736 comb 0.160000 user 0.160000 sys 0.000000 (median of 60) Differential Revision: https://phab.mercurial-scm.org/D7069

rust-utils: introduce a debug util to print the python stack trace Differential Revision: https://phab.mercurial-scm.org/D7057

rust-cross-platform: remove `unimplemented!` to get compile-time errors We should get a compile-time error that there is missing functionality for the targeted platform instead of the program breaking at runtime. Differential Revision: https://phab.mercurial-scm.org/D7107

widening: pass in matchers instead of patterns This matches how it's done for the non-ellipsis case. The oldmatch is not used yet, but it should be used eventually when widening no longer resends manifests and files the client already has. Differential Revision: https://phab.mercurial-scm.org/D7099

widening: trust user to give full "known" set The new narrow_widen wire protocol command is supposed to return data for exactly the revisions that the client requested (in order for it to be strip-free). So we should not add ancestors the client didn't ask for. Differential Revision: https://phab.mercurial-scm.org/D7098

widening: remove "depth" argument since it's always None Differential Revision: https://phab.mercurial-scm.org/D7097

widening: remove unused "heads" argument Differential Revision: https://phab.mercurial-scm.org/D7096

widening: remove pointless code for second changegroup The caller passes in common==heads, so we will never find any nodes to visit in this code and there will therefore never be a second changegroup emitted. Differential Revision: https://phab.mercurial-scm.org/D7095

widening: remove always-true condition in widening code The function is now specifically about widening, so we don't need to check if we're widening. Differential Revision: https://phab.mercurial-scm.org/D7094

narrow: drop server support for widening using the getbundle command (BC) The client still supports widening using the getbundle, which we (Google) still depend on a for a little while more (we've started the migration to the new narrow_widen command, but we're not done yet). Differential Revision: https://phab.mercurial-scm.org/D7093

widening: duplicate generateellipsesbundle2() for widening The widening and the non-widening code are quite different. It will be clearer to have them as sepearate functions. To start with, I've just copied it exactly, so it's clearer over the next few patches how they're different. The new function should gradually become more similar to bundle2.widen_bundle(), and should perhaps eventually be merged with that function. However, I've left it in narrowbundle2.py for now since it still depends on constants like _KILLNODESIGNAL there. Differential Revision: https://phab.mercurial-scm.org/D7092

tests: show graph log before and after widening in more cases I'm about to make some changes to which revisions get sent during widening. Some more tests will make it clearer what changes. I've also switched to graph log so we easily notice if the graph shape changes. Differential Revision: https://phab.mercurial-scm.org/D7091

tracing: add a couple of trace points on obsolete and repoview I was seeing weird stalls in some fast commands, and these trace events help explain them. Differential Revision: https://phab.mercurial-scm.org/D6550

dirstate: add some traces on listdir calls I'm starting to spend some time trying to make `hg status` do less work, and knowing what's happening in here and what's expensive is an important start. Differential Revision: https://phab.mercurial-scm.org/D7109

cleanup: hgdemandimport.tracing accepts strings, not bytes This does mean that the resulting traces will have some b'' goo in them on Python 3, but I think that's a worthwile price to pay since it doesn't break any tests. Differential Revision: https://phab.mercurial-scm.org/D7108