context: fix troubled deprecation troubled has been renamed into isunstable but troubled was calling unstable instead. Fix the mistake. Differential Revision: https://phab.mercurial-scm.org/D384

test-pushvars: invoke shell script hook via `sh` for Windows Invoking *.sh on Windows leads to the "what program should open this?" prompt, which stalls the test and led to the recent series of exceptions on the Windows test machine as the runner times out.

test-sparse: drop unnecessary globs

exchange: simplify unbundle locking using context managers Differential Revision: https://phab.mercurial-scm.org/D393

util: add base class for transactional context managers We have at least three types with a close() and a release() method where the close() method is supposed to be called on success and the release() method is supposed to be called last, whether successful or not. Two of them (transaction and dirstateguard) already have identical implementations of __enter__ and __exit__. Let's extract a base class for this, so we reuse the code and so the third type (transactionmanager) can also be used as a context manager. Differential Revision: https://phab.mercurial-scm.org/D392

exchange: remove need for "locked" variable The transactionmanager() constructor just assigned a few variables and cannot fail, so it's safe to move it inside the earlier try/except. Differential Revision: https://phab.mercurial-scm.org/D391

exchange: drop now-unnecessary "local" from lock name variables Since fda0867cfe03 (exchange: drop support for lock-based unbundling (BC), 2017-08-06), there is no more remote locking. Differential Revision: https://phab.mercurial-scm.org/D390

exchange: remove 'locallocked' member from pushop object The variable has been used only within a single function since 94e2862dbcfb (push: elevate phase transaction to cover entire operation, 2014-11-21), so there's no need to keep it on the pushop object. Differential Revision: https://phab.mercurial-scm.org/D389

rebase: change "result would have 3 parent" error message (BC) The old error message "cannot use revision REV as base, result would have 3 parents" is confusing - why use REV as base? why add a new parent?. This patch changes it to "cannot move parent", which seems better. Differential Revision: https://phab.mercurial-scm.org/D342

drawdag: allow override file contents via comments This makes drawdag more flexible, and allow us to create non-clean merges in test cases. Differential Revision: https://phab.mercurial-scm.org/D385