When running the test suite without building first, it is desirable to
have the tests consider these variables being undefined as equivalent
to the feature not being present, and in particular for the tests not
to generate errors.
The original nmbug format (now called version 0) creates 1
subdirectory of 'tags/' per message. This causes problems for more
than (roughly) 100k messages.
Version 1 introduces 2 layers of hashed directories. This scheme was
chose to balance the number of subdirectories with the number of extra
directories (and git objects) created via hashing.
This should be upward compatible in the sense that old repositories
will continue to work with the updated notmuch-git.
Commits or checkouts that modify a large fraction of the messages in
the database should be relatively rare (and in some automated process,
probably non-existent). For initial setup, where such operations are
expected, the user can pass --force.
This is probably more convenient than always passing a command line
argument.
Use notmuch-config for consistency with other notmuch CLI tools.
Now that there is something relevant in the config files, test the
--config option.
The previous defaults were not suitable for personal (i.e. not
bugtracking for notmuch development) use.
Provide two ways for the user to select nmbug compatible defaults;
command line argument and checking the name of the script.
If the private index file matches a previously known revision of the
database, we can update the index incrementally using the recorded
lastmod counter. This is typically much faster than a full update,
although it could be slower in the case of large changes to the
database.
The "git-read-tree HEAD" is also a bottleneck, but unfortunately
sometimes is needed. Cache the index checksum and hash to reduce the
number of times the operation is run. The overall design is a
simplified version of the PrivateIndex class.
Unlike the (current) infix query parser provided by Xapian, the
notmuch specific sexp query parser supports prefixed wildcard queries,
so use those. In addition to being somewhat faster, this avoids
needing to escape all of the user's tags to pass via the shell.
Although the code required to support both new and old environment
variables is small, it complicates the semantics of configuration, and
make the documentation harder to follow.
