Rename local variables and avoid repeated chained lookups. In
particular, avoid confusing cases like:
[...]
version = binaries[parch][0][binary][VERSION]
[...]
binaries[parch][0][binary] = self.binaries[item.suite][parch][0][binary]
version = binaries[parch][0][binary][VERSION]
Where "version" here will refer to two different versions. The former
the version from testing of a hijacked binary and the latter the
version from the source suite (despite the look up using the "testing"
table, due to the testing copy being updated).
Notable renamings:
* binaries => packages_t (a.k.a. self.binaries['testing'])
* binaries[parch][0] => binaries_t_a
* binaries[parch][1] => provides_t_a
* Similar naming used for "item.suite" instead of "testing"
The naming is based on the following logic:
* self.binaries from "packages" files
(by this logic, it ought to be "self.packages", but that is
for later)
* The "_X_a" is short for "[<suite>][<parch>]" look ups.
* binaries_X_a and provides_X_a are the specialised parts of
packages_X_a that deal with (real) binary packages and
provides (i.e. virtual packages) respectively.
Signed-off-by: Niels Thykier <niels@thykier.net>
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>
