cmdutil: make in-memory changes visible to external editor (issue4378) Before this patch, external editor process for the commit log can't view some in-memory changes (especially, of dirstate), because they aren't written out until the end of transaction (or wlock). This causes unexpected output of Mercurial commands spawned from that editor process. To make in-memory changes visible to external editor process, this patch does: - write (or schedule to write) in-memory dirstate changes, and - set HG_PENDING environment variable, if: - a transaction is running, and - there are in-memory changes to be visible "hg diff" spawned from external editor process for "hg qrefresh" shows: - "changes newly imported into the topmost" before 49148d7868df(*) - "all changes recorded in the topmost by refreshing" after this patch (*) 49148d7868df changed steps invoking editor process Even though backward compatibility may be broken, the latter behavior looks reasonable, because "hg diff" spawned from the editor process consistently shows "what changes new revision records" regardless of invocation context. In fact, issue4378 itself should be resolved by 800e090e9c64, which made 'repo.transaction()' write in-memory dirstate changes out explicitly before starting transaction. It also made "hg qrefresh" imply 'dirstate.write()' before external editor invocation in call chain below. - mq.queue.refresh - strip.strip - repair.strip - localrepository.transaction - dirstate.write - localrepository.commit - invoke external editor Though, this patch has '(issue4378)' in own summary line to indicate that issues like issue4378 should be fixed by this. BTW, this patch adds '-m' option to a 'hg ci --amend' execution in 'test-commit-amend.t', to avoid invoking external editor process. In this case, "unsure" states may be changed to "clean" according to timestamp or so on. These changes should be written into pending file, if external editor invocation is required, Then, writing dirstate changes out breaks stability of test, because it shows "transaction abort!/rollback completed" occasionally. Aborting after editor process invocation while commands below may cause similar instability of tests, too (AFAIK, there is no more such one, at this revision) - commit --amend - without --message/--logfile - import - without --message/--logfile, - without --no-commit, - without --bypass, - one of below, and - patch has no description text, or - with --edit - aborting at the 1st patch, which adds or removes file(s) - if it only changes existing files, status is checked only for changed files by 'scmutil.matchfiles()', and transition from "unsure" to "normal" in dirstate doesn't occur (= dirstate isn't changed, and written out) - aborting at the 2nd or later patch implies other pending changes (e.g. changelog), and always causes showing "transaction abort!/rollback completed"