tests: move baduisetup test inside "#if demandimport" The test case depends on the failure happening not at import time, but at uisetup() time, so it doesn't make sense when demandimport is disabled. There was already a section for testing demandimport stuff, so I moved it inside that existing section. As part of the move, I enabled the extension using '--config' so subsequent tests don't get the bad extension enabled. Differential Revision: https://phab.mercurial-scm.org/D526

revlog: abort on attempt to write null revision My repo got corrupted yesterday by something that ended up writing the null revision to the revlog (nullid hash, not nullrev index, of course). We use many extensions internally (narrowhg, remotefilelog, evolve, internal extensions) and treemanifests are on. The null revision was written to the changelog, the root manifest log, and one subdirectory manifest log. I have no idea exactly why the null revision was written, but it seems cheap enough to check that we should fail instead of corrupting the repo. Differential Revision: https://phab.mercurial-scm.org/D522

context: remove unnecessary default values for matchers (API) ctx._dirstatestatus() is called only from workingctx._buildstatus() and that function, in turn, is called only from basectx.status(). basectx.status() will always pass a matcher to _buildstatus(), so there's no need to handle a None matcher there. Differential Revision: https://phab.mercurial-scm.org/D492

context: always pass a matcher into _matchstatus() (API) This just makes it a little easier to follow and removes the need to call the superclass's method in workingctx. Differential Revision: https://phab.mercurial-scm.org/D491

test-casecollision-merge: fix the test D30 (055fee3547df) makes the error message unpredictable, therefore the fix. Differential Revision: https://phab.mercurial-scm.org/D494

run-tests: make per-line condition support testcase names 7340465bd added multiple test cases support. The latter has a problem - output lines cannot be made conditional with `#if`: ``` # COUNTEREXAMPLE: DOES NOT WORK #testcases A B $ command-foo common ouput #if A A's ouput #else B's ouput #endif common ouput ``` That's not trivial to fix (even if it works in test, `run-tests.py -i` may be suboptimal because diff algorithm does not know how to skip the `#if` lines, even if it does, it may have trouble figuring out whether a changed line belongs to inside a `#if` block or outside). Matching output lines conditionally is useful. 4eec2f04a added per-line condition support for hghave. This patch extends that to also support test case names. Differential Revision: https://phab.mercurial-scm.org/D466

simplemerge: refactor _picklabels to be more compact Use @martinvonz's suggestion from D376. Differential Revision: https://phab.mercurial-scm.org/D521