When trying to break a choice, try the candidate out and see if we can
pick it without any consequences. Basically, if the candidate causes
no new conflicts or choices, we can safely pick it.
Signed-off-by: Niels Thykier <niels@thykier.net>
For some cases, like aspell-dictionary, a number of packages can
satisfy the dependency (e.g. all aspell-*). In the particular
example, most (all?) of the aspell-* look so similar to the extent
that reverse dependencies cannot tell two aspell-* packages apart (IRT
to installability and co-installability).
This patch attempts to help the installability tester by detecting
such cases and reducing the number of candidates for a given choice.
Reported-In: <20140716134823.GA11795@x230-buxy.home.ouaza.com>
Signed-off-by: Niels Thykier <niels@thykier.net>
Extract a specialised iter_packages_hint from iter_packages that only
deals with applying hints. This simplifies iter_packages AND avoids
having to re-compute the uninstallability counters after each single
item in the hint.
This means that a hint can now avoid triggering expontential runtime
provided only that the "post-hint" stage does not trigger expontential
runtime. Previously the hint had to be ordered such that none of the
items in the hint caused such behaviour (if at all possible).
Signed-off-by: Niels Thykier <niels@thykier.net>
Avoid creating two dependency clauses for dependencies emulating a
"version range" a la:
Depends: pkg-a (>= 2), pkg-a (<< 3~)
Previously this would create two clauses a la:
- (pkg-a, 2, arch), (pkg-a, 3, arch)
- (pkg-a, 1, arch), (pkg-a, 2, arch)
However, it is plain to see that only (pkg-a, 2, arch) is a valid
solution and the other options are just noise. This patch makes
Britney merge these two claues into a single clause containing exactly
(pkg-a, 2, arch).
Signed-off-by: Niels Thykier <niels@thykier.net>
The "new" auto hinter relies on partial ordering to determine, when
what can migrate (and what needs to migrate at the same time). At the
same time, it leverages on "_compute_groups" to allow it to include
"removals" in its hints.
Signed-off-by: Niels Thykier <niels@thykier.net>
Avoid smooth-updating libraries in hints, when all of their reverse
dependencies will certainly disappear in the same hint.
Note that in "hint"-hint, reverse dependencies removed in the
following "full run" will not cause the smooth-updated library to be
removed. Instead these will still be removed in the end as usual, but
in some cases that is too late.
Signed-off-by: Niels Thykier <niels@thykier.net>
Rename find_upgraded_binaries into _compute_groups. The new method
will also compute what binaries will be updated in or added to testing
after migration.
Signed-off-by: Niels Thykier <niels@thykier.net>
Based on Colin Watson's code to do the same from the "britney2-ubuntu"
repository[1] revision 306, 308 and 309.
Notable differences include:
* output include version of source package being removed
* output prefix removals with a "-" (otherwise it would be identical to
a upgrade/new source with the change above).
[1] http://bazaar.launchpad.net/~ubuntu-release/britney/britney2-ubuntu/revision/306
Signed-off-by: Niels Thykier <niels@thykier.net>
This introduces a new variable HINTSDIR, which overrides the location of the
Hints dir (normally it is read from the UNSTABLE dir).
Please note that this is the location of the dir that contains the Hints dir.
Signed-off-by: Niels Thykier <niels@thykier.net>
This introduces a new variable OUTPUTDIR, which overrides the location where
the new dates file is written. This allow to run britney against a read-only
copy of the data.
Signed-off-by: Niels Thykier <niels@thykier.net>
Set the default to maxint until we've read something.
Reported-by: Ivo De Decker <ivo.dedecker@ugent.be>
Signed-off-by: Julien Cristau <jcristau@debian.org>
If an architecture is marked as fucked, britney's package list for that
architecture may include arch:all packages for an older version. When
outputting the result file, we should not include those packages as
they will lead to import failures.
Signed-off-by: Adam D. Barratt <adam@adam-barratt.org.uk>
Niels Thykier
Adam D. Barratt
Julien Cristau
Philipp Kern
Ivo De Decker