inst-builder: Split relation loop and optimize conflicts

Signed-off-by: Niels Thykier <niels@thykier.net>

britney2/installability/builder.py

@@ -50,24 +50,25 @@ def build_installability_tester(suite_info, archs):
 
             with builder.relation_builder(pkg_id) as relations:
 
-                for (al, dep) in [(depends, True), (conflicts, False)]:
+                # Breaks/Conflicts are so simple that we do not need to keep align the relation
-
+                # with the suite.  This enables us to do a few optimizations.
-                    for block in al:
+                if conflicts:
+                    for dep_suite in suite_info:
+                        dep_binaries_s_a, dep_provides_s_a = dep_suite.binaries[arch]
+                        for block in (relation for relation in conflicts):
+                            # if a package satisfies its own conflicts relation, then it is using §7.6.2
+                            rels = (s.pkg_id for s in solvers(block, dep_binaries_s_a, dep_provides_s_a)
+                                        if s.pkg_id != pkg_id)
+                            for r in rels:
+                                relations.add_breaks(r)
+
+                for block in depends:
                     sat = set()
 
                     for dep_suite in suite_info:
                         dep_binaries_s_a, dep_provides_s_a = dep_suite.binaries[arch]
-                            pkgs = solvers(block, dep_binaries_s_a, dep_provides_s_a)
+                        sat.update(s.pkg_id for s in solvers(block, dep_binaries_s_a, dep_provides_s_a))
-                            for pdata in pkgs:
+
-                                dep_pkg_id = pdata.pkg_id
-                                if dep:
-                                    sat.add(dep_pkg_id)
-                                elif pkg_id != dep_pkg_id:
-                                    # if t satisfies its own
-                                    # conflicts relation, then it
-                                    # is using §7.6.2
-                                    relations.add_breaks(dep_pkg_id)
-                        if dep:
                     if len(block) != 1:
                         relations.add_dependency_clause(sat)
                     else:
@@ -96,7 +97,6 @@ def build_installability_tester(suite_info, archs):
                         else:
                             possible_dep_ranges[key] = sat
 
-                    if dep:
                 for clause in possible_dep_ranges.values():
                     relations.add_dependency_clause(clause)