@ -12,6 +12,7 @@
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
from collections import defaultdict
from contextlib import contextmanager
from britney_util import ifilter_except , iter_except
@ -28,7 +29,7 @@ class _RelationBuilder(object):
self . _new_breaks = set ( binary_data [ 1 ] )
def add_dependency_clause ( self , or_clause :
def add_dependency_clause ( self , or_clause , frozenset = frozenset ):
""" Add a dependency clause
The clause must be a sequence of ( name , version , architecture )
@ -48,12 +49,12 @@ class _RelationBuilder(object):
binary = self . _binary
itbuilder = self . _itbuilder
package_table = itbuilder . _package_table
reverse_package_table = itbuilder . _reverse_package_table
okay = False
for dep_tuple in clause :
okay = True
reverse_relations = itbuilder . _reverse_relations ( dep_tuple )
reverse_relations [ 0 ] . add ( binary )
rdeps , _ , rdep_relations = itbuilder . _reverse_relations ( dep_tuple )
rdeps . add ( binary )
rdep_relations . add ( clause )
self . _new_deps . add ( clause )
if not okay :
@ -193,7 +194,7 @@ class InstallabilityTesterBuilder(object):
if binary in self . _reverse_package_table :
return self . _reverse_package_table [ binary ]
rel = [ set ( ) , set ( )
rel = [ set ( ) , set ( ) , set ( ) ]
self . _reverse_package_table [ binary ] = rel
return rel
@ -227,18 +228,21 @@ class InstallabilityTesterBuilder(object):
# operations in _check_loop since we only have to check one
# set (instead of two) and we remove a few duplicates here
# and there.
#
# At the same time, intern the rdep sets
for pkg in reverse_package_table :
if pkg not in package_table :
raise RuntimeError ( " %s / %s / %s referenced but not added! " % pkg )
if not reverse_package_table [ pkg ] [ 1 ] :
# no rconflicts - ignore
continue
deps , con = package_table [ pkg ]
if not con :
con = intern_set ( reverse_package_table [ pkg ] [ 1 ] )
else :
con = intern_set ( con | reverse_package_table [ pkg ] [ 1 ] )
package_table [ pkg ] = ( deps , con )
rdeps , rcon , rdep_relations = reverse_package_table [ pkg ]
if rcon :
if not con :
con = intern_set ( rcon )
else :
con = intern_set ( con | rcon )
package_table [ pkg ] = ( deps , con )
reverse_package_table [ pkg ] = ( intern_set ( rdeps ) , con ,
intern_set ( rdep_relations ) )
# Check if we can expand broken.
for t in not_broken ( iter_except ( check . pop , KeyError ) ) :
@ -308,8 +312,95 @@ class InstallabilityTesterBuilder(object):
# add all rdeps (except those already in the safe_set)
check . update ( reverse_package_table [ pkg ] [ 0 ] - safe_set )
eqv_table = self . _build_eqv_packages_table ( package_table ,
reverse_package_table )
return InstallabilitySolver ( package_table ,
reverse_package_table ,
self . _testing , self . _broken ,
self . _essentials , safe_set )
self . _essentials , safe_set ,
eqv_table )
def _build_eqv_packages_table ( self , package_table ,
reverse_package_table ,
frozenset = frozenset ) :
""" Attempt to build a table of equivalent packages
This method attempts to create a table of packages that are
equivalent ( in terms of installability ) . If two packages ( A
and B ) are equivalent then testing the installability of A is
the same as testing the installability of B . This equivalency
also applies to co - installability .
The example cases :
* aspell - *
* ispell - *
Cases that do * not * apply :
* MTA ' s
The theory :
The packages A and B are equivalent iff :
reverse_depends ( A ) == reverse_depends ( B ) AND
conflicts ( A ) == conflicts ( B ) AND
depends ( A ) == depends ( B )
Where " reverse_depends(X) " is the set of reverse dependencies
of X , " conflicts(X) " is the set of negative dependencies of X
( Breaks and Conflicts plus the reverse ones of those combined )
and " depends(X) " is the set of strong dependencies of X
( Depends and Pre - Depends combined ) .
To be honest , we are actually equally interested another
property as well , namely substitutability . The package A can
always used instead of B , iff :
reverse_depends ( A ) > = reverse_depends ( B ) AND
conflicts ( A ) < = conflicts ( B ) AND
depends ( A ) == depends ( B )
( With the same definitions as above ) . Note that equivalency
is just a special - case of substitutability , where A and B can
substitute each other ( i . e . a two - way substituation ) .
Finally , note that the " depends(A) == depends(B) " for
substitutability is actually not a strict requirement . There
are cases where those sets are different without affecting the
property .
"""
# Despite talking about substitutability, the method currently
# only finds the equivalence cases. Lets leave
# substitutability for a future version.
find_eqv_table = defaultdict ( list )
eqv_table = { }
for pkg in reverse_package_table :
rdeps = reverse_package_table [ pkg ] [ 2 ]
if not rdeps :
# we don't care for things without rdeps (because
# it is not worth it)
continue
deps , con = package_table [ pkg ]
ekey = ( deps , con , rdeps )
find_eqv_table [ ekey ] . append ( pkg )
for pkg_list in find_eqv_table . itervalues ( ) :
if len ( pkg_list ) < 2 :
continue
if ( len ( pkg_list ) == 2 and pkg_list [ 0 ] [ 0 ] == pkg_list [ 1 ] [ 0 ]
and pkg_list [ 0 ] [ 2 ] == pkg_list [ 1 ] [ 2 ] ) :
# This is a (most likely) common and boring case. It
# is when pkgA depends on pkgB and is satisfied with
# any version available. However, at most one version
# of pkgB will be available in testing, so other
# filters will make this case redundant.
continue
eqv_set = frozenset ( pkg_list )
for pkg in pkg_list :
eqv_table [ pkg ] = eqv_set
return eqv_table
Niels Thykier
11 years ago