test-obsolete-bounds-checking: make the test compatible with chg This test fails when run with chg because the error message starts with "ProgrammingError" instead of "mercurial.error.ProgrammingError". Therefore, globing the "mercurial.error." to ensure that the test is compatible with chg. Test Plan: Ran the test 'test-obsolete-bounds-checking.t' with and without the '--chg' option. Differential Revision: https://phab.mercurial-scm.org/D1127

test-dispatch: make the test compatible with chg The test is broken when run with chg because it prints a different error message when chg is running. This commit fixes the test by special casing for chg. Test Plan: Ran the test 'test-dispatch.t' with and without '--chg' option. Differential Revision: https://phab.mercurial-scm.org/D1126

histedit: remove the nonexistant config 'histeditng' D942 removed the experimental config 'histeditng'. This is a leftover which should have been removed in that commit. Therefore, this commit completes the cleanup. Test Plan: Ran all the tests. Differential Revision: https://phab.mercurial-scm.org/D1123

context: add workingfilectx.markcopied With in-memory merge, copy information needs to be stored in-memory, not in the dirstate. To make this transition easy, move the existing dirstate-based approach to workingfilectx; that way, other implementations can choose to store it somewhere else. Differential Revision: https://phab.mercurial-scm.org/D1106

merge: don't use workers in in-memory mode The worker processes can't share memory, so workers should not be used. Differential Revision: https://phab.mercurial-scm.org/D1105

filemerge: add a missing flushall() Differential Revision: https://phab.mercurial-scm.org/D1060

filemerge: store backups in the overlayworkingctx if using imm Differential Revision: https://phab.mercurial-scm.org/D1059