progress: demonstrate non-linear progress has a bad ETA experience Previously, the ETA and speed assumes the progress is linear. Often, due to network or other issues, it could be fast for the most time, and suddenly slow down: [====================================================> ] \___________________________________________/\______/ very fast suddenly much slower This patch adds a test demonstrating the ETA could be way off in those cases. Differential Revision: https://phab.mercurial-scm.org/D819

copytrace: add a a new config to limit the number of drafts in heuristics The heuristics options tries to the default full copytracing algorithm if both the source and destination branches contains of non-public changesets only. But this can be slow in cases when we have a lot of drafts. This patch adds a new config option experimental.copytrace.sourcecommitlimit which defaults to 100. This value will be the limit of number of drafts from c1 to base. Incase there are more changesets even though they are draft, the heuristics algorithm will be used. Differential Revision: https://phab.mercurial-scm.org/D763

mail: encode long unicode lines in emails properly (issue5687) 3e544c074459 introduced a bug: emails Content-Transfer-Encoding is silently replaced with 'quoted-printable' while any other encoding could be used by underlying code. The problem is revealed when a long unicode line is encoded. The patch implements proper check which works for any text and encoding.