solver3: Reject reverse dependencies natively

Instead of utilizing the reverse depends functionality of the cache
and marking all possible reverse dependencies for removal, mark them
ourselves by keeping track of reverse-implication-clauses.

Notably, this improves the reverse dependency rejection substantially:
The previous RejectReverseDependencies() function did not handle
Provides.

For this to work correctly right now, we need to discover optional
clauses too when queuing them. This is somewhat suboptimal as we
technically we don't care if they become unsat, we just waste time
tracking them.

The tests get a bit awkward, but oh well, we use what we can
use.

5 files changed, 9 insertions, 18 deletions

diff --git a/test/integration/test-apt-get-build-dep-barbarian b/test/integration/test-apt-get-build-dep-barbarian
index b8ab1211b..e070e96ca 100755
--- a/test/integration/test-apt-get-build-dep-barbarian
+++ b/test/integration/test-apt-get-build-dep-barbarian
@@ -83,7 +83,7 @@ testsuccessequal "$(installsfoosamey 'amd64' 'i386')" apt build-dep cool-foo -s
 testsuccessequal "$(installsfoosamey 'i386' 'i386')" apt build-dep bad-amd64-foo -s -a i386
 testsuccessequal "$(installsfoosamey 'amd64' 'i386')" apt build-dep bad-armel-foo -s -a i386
 testsuccessequal "$(installsfoosamey 'i386' 'i386')" apt build-dep bad-amd64-armel-foo -s -a i386
-testfailuremsg 'E: Conflict: builddeps:bad-amd64-i386-foo:i386=1 -> not foo:i386=1 -> not builddeps:bad-amd64-i386-foo:i386=1 but builddeps:bad-amd64-i386-foo:i386=1'  apt build-dep bad-amd64-i386-foo -s -a i386 --solver 3.0
+testfailuremsg 'E: Conflict: builddeps:bad-amd64-i386-foo:i386=1 -> not foo:amd64=1 -> not builddeps:bad-amd64-i386-foo:i386=1 but builddeps:bad-amd64-i386-foo:i386=1'  apt build-dep bad-amd64-i386-foo -s -a i386 --solver 3.0
 testfailureequal 'Reading package lists...
 Reading package lists...
 Building dependency tree...
@@ -96,7 +96,7 @@ The following information may help to resolve the situation:
 The following packages have unmet dependencies:
  builddeps:bad-amd64-i386-foo:i386 : Depends: foo:i386
 E: Unable to correct problems, you have held broken packages.' apt build-dep bad-amd64-i386-foo -s -a i386 --solver internal
-testfailuremsg 'E: Conflict: builddeps:bad-amd64-i386-armel-foo:i386=1 -> not foo:i386=1 -> not builddeps:bad-amd64-i386-armel-foo:i386=1 but builddeps:bad-amd64-i386-armel-foo:i386=1' apt build-dep bad-amd64-i386-armel-foo -s -a i386 --solver 3.0
+testfailuremsg 'E: Conflict: builddeps:bad-amd64-i386-armel-foo:i386=1 -> not foo:amd64=1 -> not builddeps:bad-amd64-i386-armel-foo:i386=1 but builddeps:bad-amd64-i386-armel-foo:i386=1' apt build-dep bad-amd64-i386-armel-foo -s -a i386 --solver 3.0
 testfailureequal 'Reading package lists...
 Reading package lists...
 Building dependency tree...
@@ -115,7 +115,7 @@ testsuccessequal "$(installsfoosamey 'i386' 'armel')" apt build-dep bad-amd64-fo
 testsuccessequal "$(installsfoosamey 'amd64' 'armel')" apt build-dep bad-armel-foo -s -a armel
 testsuccessequal "$(installsfoosamey 'i386' 'armel')" apt build-dep bad-amd64-armel-foo -s -a armel
 testsuccessequal "$(installsfoosamey 'armel' 'armel')" apt build-dep bad-amd64-i386-foo -s -a armel
-FAILUREMSG="E: Conflict: builddeps:bad-amd64-i386-armel-foo:armel=1 -> not foo:armel=1 -> not builddeps:bad-amd64-i386-armel-foo:armel=1 but builddeps:bad-amd64-i386-armel-foo:armel=1"
+FAILUREMSG="E: Conflict: builddeps:bad-amd64-i386-armel-foo:armel=1 -> not foo:amd64=1 -> not builddeps:bad-amd64-i386-armel-foo:armel=1 but builddeps:bad-amd64-i386-armel-foo:armel=1"
 FAILURE='Reading package lists...
 Building dependency tree...
 Some packages could not be installed. This may mean that you have
diff --git a/test/integration/test-apt-never-markauto-sections b/test/integration/test-apt-never-markauto-sections
index e60a6e648..4d7324b02 100755
--- a/test/integration/test-apt-never-markauto-sections
+++ b/test/integration/test-apt-never-markauto-sections
@@ -49,7 +49,7 @@ Remv foreignpkg:i386 [1]
 Remv nosection [1]
 Remv texteditor [1]' aptget autoremove mydesktop -s
 
-testfailuremsg 'E: Conflict: not texteditor:amd64 -> not texteditor:amd64=1 -> not mydesktop-core:amd64=1 but mydesktop:amd64 -> mydesktop-core:amd64 -> mydesktop-core:amd64=1' aptget autoremove texteditor -s --solver 3.0 #-o Debug::pkgDepCache::AutoInstall=1 -o Debug::pkgProblemResolver=1 -o Debug::pkgDepCache::Marker=1
+testfailuremsg 'E: Conflict: not texteditor:amd64 -> not bad-texteditor:amd64 -> not mydesktop-core:amd64 but mydesktop:amd64 -> mydesktop-core:amd64' aptget autoremove texteditor -s --solver 3.0 #-o Debug::pkgDepCache::AutoInstall=1 -o Debug::pkgProblemResolver=1 -o Debug::pkgDepCache::Marker=1
 testsuccessequal 'Reading package lists...
 Building dependency tree...
 Reading state information...
diff --git a/test/integration/test-bug-618848-always-respect-user-requests b/test/integration/test-bug-618848-always-respect-user-requests
index 8ba750b44..d59491af6 100755
--- a/test/integration/test-bug-618848-always-respect-user-requests
+++ b/test/integration/test-bug-618848-always-respect-user-requests
@@ -14,7 +14,7 @@ insertpackage 'unstable' 'exim4-daemon-heavy' 'all' '1.0' 'Depends: libdb4.8'
 setupaptarchive
 
 # This does not work in 3.0 solver: We do not remove manually installed packages.
-testfailuremsg "E: Conflict: exim4-daemon-light:i386 -> libdb4.8:i386 but not libdb4.8:i386" aptget remove libdb4.8 --solver 3.0 -s
+testfailuremsg "E: Conflict: not libdb4.8:i386 -> not exim4-daemon-light:i386 but exim4-daemon-light:i386" aptget remove libdb4.8 --solver 3.0 -s
 allowremovemanual
 testsuccessequal "Reading package lists...
 Building dependency tree...
diff --git a/test/integration/test-multiarch-allowed b/test/integration/test-multiarch-allowed
index 9fc49275a..fb8cb653d 100755
--- a/test/integration/test-multiarch-allowed
+++ b/test/integration/test-multiarch-allowed
@@ -64,24 +64,18 @@ Inst needsfoo:i386 (1 unstable [i386])
 Conf foo:i386 (1 unstable [i386])
 Conf needsfoo:i386 (1 unstable [i386])' aptget install needsfoo:i386 -s
 # FIXME: same problem, but two different unmet dependency messages depending on install order
-testfailuremsg "E: Conflict: needsfoo:i386=1 -> foo:i386 but no versions are installable
-E: Uninstallable version: foo:amd64=1 -> not foo:i386=1
-E: Uninstallable version: foo:amd64=1 -> not foo:i386=1" aptget install needsfoo:i386 foo:amd64 -s --solver 3.0
+testfailuremsg "E: Conflict: foo:amd64=1 -> not foo:i386=1 -> not foo:i386 but needsfoo:i386=1 -> foo:i386" aptget install needsfoo:i386 foo:amd64 -s --solver 3.0
 testfailureequal "$BADPREFIX
 The following packages have unmet dependencies:
  foo : Conflicts: foo:i386 but 1 is to be installed
  foo:i386 : Conflicts: foo but 1 is to be installed
 E: Unable to correct problems, you have held broken packages." aptget install needsfoo:i386 foo:amd64 -s --solver internal
-testfailuremsg "E: Conflict: needsfoo:i386=1 -> foo:i386 but no versions are installable
-E: Uninstallable version: foo:amd64=1 -> not foo:i386=1
-E: Uninstallable version: foo:amd64=1 -> not foo:i386=1" aptget install foo:amd64 needsfoo:i386 -s --solver 3.0
+testfailuremsg "E: Conflict: foo:amd64=1 -> not foo:i386=1 -> not foo:i386 but needsfoo:i386=1 -> foo:i386" aptget install foo:amd64 needsfoo:i386 -s --solver 3.0
 testfailureequal "$BADPREFIX
 The following packages have unmet dependencies:
  needsfoo:i386 : Depends: foo:i386 but it is not installable
 E: Unable to correct problems, you have held broken packages." aptget install foo:amd64 needsfoo:i386 -s --solver internal
-testfailuremsg "E: Conflict: needsfoo:amd64=1 -> foo:amd64 but no versions are installable
-E: Uninstallable version: foo:i386=1 -> not foo:amd64=1
-E: Uninstallable version: foo:i386=1 -> not foo:amd64=1" aptget install needsfoo foo:i386 -s --solver 3.0
+testfailuremsg "E: Conflict: foo:i386=1 -> not foo:amd64=1 -> not foo:amd64 but needsfoo:amd64=1 -> foo:amd64" aptget install needsfoo foo:i386 -s --solver 3.0
 testfailureequal "$BADPREFIX
 The following packages have unmet dependencies:
  foo : Conflicts: foo:i386 but 1 is to be installed
diff --git a/test/integration/test-prefer-higher-priority-providers b/test/integration/test-prefer-higher-priority-providers
index 5fed20a59..76a03b3fb 100755
--- a/test/integration/test-prefer-higher-priority-providers
+++ b/test/integration/test-prefer-higher-priority-providers
@@ -91,10 +91,7 @@ Inst awesome (1 unstable [all])
 Conf baz (1 unstable [all])
 Conf awesome (1 unstable [all])" aptget install awesome foo- bar- -s
 
-testfailuremsg "E: Unsatisfiable dependency: awesome:$native=1 -> foo:$native=1 | bar:$native=1 | baz:$native=1
-E: Not considered: foo:$native=1: not foo:$native -> not foo:$native=1
-E: Not considered: bar:$native=1: not bar:$native -> not bar:$native=1
-E: Not considered: baz:$native=1: not baz:$native -> not baz:$native=1" aptget install awesome foo- bar- baz- -s --solver 3.0
+testfailuremsg "E: Conflict: awesome:$native=1 -> baz:$native=1 -> baz:$native but not baz:$native" aptget install awesome foo- bar- baz- -s --solver 3.0
 testfailureequal "Reading package lists...
 Building dependency tree...
 Package 'foo' is not installed, so not removed