templater: give better error message for invalid engine type Before, KeyError was caught at changeset_templater._show(), which said "no key named '%s'" as it was intended to catch the KeyError of unknown map key. Instead, we should catch KeyError explicitly for better error indication. For those who don't know what the template engine is (read "everyone"), it is hidden extension feature that allows switching template syntax in map file. See d8c5a7f25a40 for details.

transaction: allow running file generators after finalizers Previously, transaction.close would run the file generators before running the finalizers (see the list below for what is in each). Since file generators contain the bookmarks and the dirstate, this meant we made the dirstate and bookmarks visible to external readers before we actually wrote the commits into the changelog, which could result in missing bookmarks and missing working copy parents (especially on servers with high commit throughput, since pulls might fail to see certain bookmarks in this situation). By moving the changelog writing to be before the bookmark/dirstate writing, we ensure the commits are present before they are referenced. This implementation allows certain file generators to be after the finalizers. We didn't want to move all of the generators, since it's important that things like phases actually run before the finalizers (otherwise you could expose commits as public when they really shouldn't be). For reference, file generators currently consist of: bookmarks, dirstate, and phases. Finalizers currently consist of: changelog, revbranchcache, and fncache.

run-tests: move install.err into test area Without this, sometimes installerrs generated errors about no such file. It also did not work well when you had multiple tests runners running around. It also did not make sense to pollute the repository test directory with the log file.