Add upgrade by using only the SAT core

- Adds upgrade --universe and upgrade --universe --clean. It will
  attempt to bring the system as much close as the content available in
  the repositories. It differs from a standard upgrade which checks
  directly that what is pulled in doesn't conflict with the system. In
  this new way, we just query the SAT solver to decide that on our
  behalf.
- Add uninstall --full-clean. It uses only the SAT solver to uninstall
  the package and it will drop as many packages as required (including
  revdeps of packages too.

pkg/solver/solver.go

@@ -38,6 +38,9 @@ type PackageSolver interface {
 	World() pkg.Packages
 	Upgrade(checkconflicts, full bool) (pkg.Packages, PackagesAssertions, error)
 
+	UpgradeUniverse(dropremoved bool) (pkg.Packages, PackagesAssertions, error)
+	UninstallUniverse(toremove pkg.Packages) (pkg.Packages, error)
+
 	SetResolver(PackageResolver)
 
 	Solve() (PackagesAssertions, error)
@@ -95,6 +98,16 @@ func (s *Solver) noRulesWorld() bool {
 	return true
 }
 
+func (s *Solver) noRulesInstalled() bool {
+	for _, p := range s.Installed() {
+		if len(p.GetConflicts()) != 0 || len(p.GetRequires()) != 0 {
+			return false
+		}
+	}
+
+	return true
+}
+
 func (s *Solver) BuildInstalled() (bf.Formula, error) {
 	var formulas []bf.Formula
 	for _, p := range s.Installed() {
@@ -251,6 +264,163 @@ func (s *Solver) ConflictsWithInstalled(p pkg.Package) (bool, error) {
 	return s.ConflictsWith(p, s.Installed())
 }
 
+// UninstallUniverse takes a list of candidate package and return a list of packages that would be removed
+// in order to purge the candidate. Uses the solver to check constraints and nothing else
+//
+// It can be compared to the counterpart Uninstall as this method acts like a uninstall --full
+// it removes all the packages and its deps. taking also in consideration other packages that might have
+// revdeps
+func (s *Solver) UninstallUniverse(toremove pkg.Packages) (pkg.Packages, error) {
+
+	if s.noRulesInstalled() {
+		return s.getList(s.InstalledDatabase, toremove)
+	}
+
+	// resolve to packages from the db
+	toRemove, err := s.getList(s.InstalledDatabase, toremove)
+	if err != nil {
+		return nil, errors.Wrap(err, "Package not found in definition db")
+	}
+
+	var formulas []bf.Formula
+	r, err := s.BuildInstalled()
+	if err != nil {
+		return nil, errors.Wrap(err, "Package not found in definition db")
+	}
+
+	// SAT encode the clauses against the world
+	for _, p := range toRemove.Unique() {
+		encodedP, err := p.Encode(s.InstalledDatabase)
+		if err != nil {
+			return nil, errors.Wrap(err, "Package not found in definition db")
+		}
+		P := bf.Var(encodedP)
+		formulas = append(formulas, bf.And(bf.Not(P), r))
+	}
+
+	markedForRemoval := pkg.Packages{}
+	model := bf.Solve(bf.And(formulas...))
+	if model == nil {
+		return nil, errors.New("Failed finding a solution")
+	}
+	assertion, err := DecodeModel(model, s.InstalledDatabase)
+	if err != nil {
+		return nil, errors.Wrap(err, "while decoding model from solution")
+	}
+	for _, a := range assertion {
+		if !a.Value {
+			if p, err := s.InstalledDatabase.FindPackage(a.Package); err == nil {
+				markedForRemoval = append(markedForRemoval, p)
+			}
+
+		}
+	}
+	return markedForRemoval, nil
+}
+
+// UpgradeUniverse mark packages for removal and returns a solution. It considers
+// the Universe db as authoritative
+// See also on the subject: https://arxiv.org/pdf/1007.1021.pdf
+func (s *Solver) UpgradeUniverse(dropremoved bool) (pkg.Packages, PackagesAssertions, error) {
+	// we first figure out which aren't up-to-date
+	// which has to be removed
+	// and which needs to be upgraded
+	notUptodate := pkg.Packages{}
+	removed := pkg.Packages{}
+	toUpgrade := pkg.Packages{}
+
+	// TODO: this is memory expensive, we need to optimize this
+	universe := pkg.NewInMemoryDatabase(false)
+	for _, p := range s.DefinitionDatabase.World() {
+		universe.CreatePackage(p)
+	}
+	for _, p := range s.Installed() {
+		universe.CreatePackage(p)
+	}
+
+	// Grab all the installed ones, see if they are eligible for update
+	for _, p := range s.Installed() {
+		available, err := universe.FindPackageVersions(p)
+		if err != nil {
+			removed = append(removed, p)
+		}
+		if len(available) == 0 {
+			continue
+		}
+
+		bestmatch := available.Best(nil)
+		// Found a better version available
+		if !bestmatch.Matches(p) {
+			notUptodate = append(notUptodate, p)
+			toUpgrade = append(toUpgrade, bestmatch)
+		}
+	}
+
+	// resolve to packages from the db to be able to encode correctly
+	oldPackages, err := s.getList(universe, notUptodate)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "couldn't get package marked for removal from universe")
+	}
+
+	updates, err := s.getList(universe, toUpgrade)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "couldn't get package marked for update from universe")
+	}
+
+	var formulas []bf.Formula
+
+	// Build constraints for the whole defdb
+	r, err := s.BuildWorld(true)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "couldn't build world constraints")
+	}
+
+	// Treat removed packages from universe as marked for deletion
+	if dropremoved {
+		oldPackages = append(oldPackages, removed...)
+	}
+
+	// SAT encode the clauses against the world
+	for _, p := range oldPackages.Unique() {
+		encodedP, err := p.Encode(universe)
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "couldn't encode package")
+		}
+		P := bf.Var(encodedP)
+		formulas = append(formulas, bf.And(bf.Not(P), r))
+	}
+
+	for _, p := range updates {
+		encodedP, err := p.Encode(universe)
+		if err != nil {
+			return nil, nil, errors.Wrap(err, "couldn't encode package")
+		}
+		P := bf.Var(encodedP)
+		formulas = append(formulas, bf.And(P, r))
+	}
+
+	markedForRemoval := pkg.Packages{}
+	model := bf.Solve(bf.And(formulas...))
+	if model == nil {
+		return nil, nil, errors.New("Failed finding a solution")
+	}
+
+	assertion, err := DecodeModel(model, universe)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "while decoding model from solution")
+	}
+	for _, a := range assertion {
+		if !a.Value {
+			if p, err := s.InstalledDatabase.FindPackage(a.Package); err == nil {
+				markedForRemoval = append(markedForRemoval, p)
+			}
+
+		}
+
+	}
+	return markedForRemoval, assertion, nil
+}
+
 func (s *Solver) Upgrade(checkconflicts, full bool) (pkg.Packages, PackagesAssertions, error) {
 
 	// First get candidates that needs to be upgraded..

pkg/solver/solver_test.go

@@ -574,57 +574,366 @@ var _ = Describe("Solver", func() {
 			Expect(err).ToNot(HaveOccurred())
 		})
 
-		It("Uninstalls simple package correctly", func() {
+		Context("Uninstall", func() {
+			It("Uninstalls simple package correctly", func() {
 
-			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
 
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbDefinitions.CreatePackage(p)
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				s = NewSolver(dbInstalled, dbDefinitions, db)
+
+				solution, err := s.Uninstall(A, true, true)
 				Expect(err).ToNot(HaveOccurred())
-			}
 
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbInstalled.CreatePackage(p)
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+
+				//	Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
+				Expect(len(solution)).To(Equal(1))
+			})
+			It("Uninstalls simple package expanded correctly", func() {
+
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "1.2", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				s = NewSolver(dbInstalled, dbDefinitions, db)
+
+				solution, err := s.Uninstall(&pkg.DefaultPackage{Name: "A", Version: ">1.0"}, true, true)
 				Expect(err).ToNot(HaveOccurred())
-			}
-			s = NewSolver(dbInstalled, dbDefinitions, db)
 
-			solution, err := s.Uninstall(A, true, true)
-			Expect(err).ToNot(HaveOccurred())
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
 
-			Expect(solution).To(ContainElement(A.IsFlagged(false)))
+				//	Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
+				Expect(len(solution)).To(Equal(1))
+			})
+			It("Uninstalls simple packages not in world correctly", func() {
 
-			//	Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
-			Expect(len(solution)).To(Equal(1))
-		})
-		It("Uninstalls simple package expanded correctly", func() {
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
 
-			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			A := pkg.NewPackage("A", "1.2", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				for _, p := range []pkg.Package{B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
 
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbDefinitions.CreatePackage(p)
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				solution, err := s.Uninstall(A, true, true)
 				Expect(err).ToNot(HaveOccurred())
-			}
 
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbInstalled.CreatePackage(p)
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+
+				//	Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
+				Expect(len(solution)).To(Equal(1))
+			})
+
+			It("Uninstalls complex packages not in world correctly", func() {
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				solution, err := s.Uninstall(A, true, true)
 				Expect(err).ToNot(HaveOccurred())
-			}
-			s = NewSolver(dbInstalled, dbDefinitions, db)
 
-			solution, err := s.Uninstall(&pkg.DefaultPackage{Name: "A", Version: ">1.0"}, true, true)
-			Expect(err).ToNot(HaveOccurred())
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
 
-			Expect(solution).To(ContainElement(A.IsFlagged(false)))
+				Expect(len(solution)).To(Equal(1))
+			})
+
+			It("Uninstalls complex packages correctly, even if shared deps are required by system packages", func() {
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				solution, err := s.Uninstall(A, true, true)
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+				Expect(solution).ToNot(ContainElement(B.IsFlagged(false)))
+
+				Expect(len(solution)).To(Equal(1))
+			})
+
+			It("Uninstalls complex packages in world correctly", func() {
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{C}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				solution, err := s.Uninstall(A, true, true)
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+				Expect(solution).To(ContainElement(C.IsFlagged(false)))
+
+				Expect(len(solution)).To(Equal(2))
+			})
+
+			It("Uninstalls complex package correctly", func() {
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{D}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
+				//	C // installed
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				solution, err := s.Uninstall(A, true, true)
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+				Expect(solution).To(ContainElement(B.IsFlagged(false)))
+				Expect(solution).To(ContainElement(D.IsFlagged(false)))
+
+				Expect(len(solution)).To(Equal(3))
+
+			})
+
+			It("UninstallUniverse simple package correctly", func() {
+
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				s = NewSolver(dbInstalled, dbDefinitions, db)
+
+				solution, err := s.UninstallUniverse(pkg.Packages{A})
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+
+				//	Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
+				Expect(len(solution)).To(Equal(1))
+			})
+			It("UninstallUniverse simple package expanded correctly", func() {
+
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "1.2", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				s = NewSolver(dbInstalled, dbDefinitions, db)
+
+				solution, err := s.UninstallUniverse(pkg.Packages{
+					&pkg.DefaultPackage{Name: "A", Version: ">1.0"}})
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+
+				//	Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
+				Expect(len(solution)).To(Equal(1))
+			})
+			It("UninstallUniverse simple packages not in world correctly", func() {
+
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				solution, err := s.UninstallUniverse(pkg.Packages{A})
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+
+				//	Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
+				Expect(len(solution)).To(Equal(1))
+			})
+
+			It("UninstallUniverse complex packages not in world correctly", func() {
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				solution, err := s.UninstallUniverse(pkg.Packages{A})
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+				Expect(solution).To(ContainElement(B.IsFlagged(false)))
+
+				Expect(len(solution)).To(Equal(2))
+			})
+
+			It("UninstallUniverse complex packages correctly, even if shared deps are required by system packages", func() {
+				// Here we diff a lot from standard Uninstall:
+				// all the packages that has reverse deps will be removed (aka --full)
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+				solution, err := s.UninstallUniverse(pkg.Packages{A})
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+				Expect(solution).To(ContainElement(B.IsFlagged(false)))
+				Expect(solution).To(ContainElement(C.IsFlagged(false)))
+
+				Expect(len(solution)).To(Equal(3))
+			})
+
+			It("UninstallUniverse complex packages in world correctly", func() {
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{C}, []*pkg.DefaultPackage{})
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				solution, err := s.UninstallUniverse(pkg.Packages{A})
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+				Expect(solution).To(ContainElement(C.IsFlagged(false)))
+
+				Expect(len(solution)).To(Equal(2))
+			})
+
+			It("UninstallUniverse complex package correctly", func() {
+				C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
+				B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{D}, []*pkg.DefaultPackage{})
+				A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
+				//	C // installed
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbDefinitions.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				for _, p := range []pkg.Package{A, B, C, D} {
+					_, err := dbInstalled.CreatePackage(p)
+					Expect(err).ToNot(HaveOccurred())
+				}
+
+				solution, err := s.UninstallUniverse(pkg.Packages{A})
+				Expect(err).ToNot(HaveOccurred())
+
+				Expect(solution).To(ContainElement(A.IsFlagged(false)))
+				Expect(solution).To(ContainElement(B.IsFlagged(false)))
+				Expect(solution).To(ContainElement(D.IsFlagged(false)))
+
+				Expect(len(solution)).To(Equal(3))
+
+			})
 
-			//	Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
-			Expect(len(solution)).To(Equal(1))
 		})
 		It("Find conflicts", func() {
 
@@ -810,131 +1119,6 @@ var _ = Describe("Solver", func() {
 			Expect(val).ToNot(BeTrue())
 		})
 
-		It("Uninstalls simple packages not in world correctly", func() {
-
-			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-
-			for _, p := range []pkg.Package{B, C, D} {
-				_, err := dbDefinitions.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbInstalled.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-			solution, err := s.Uninstall(A, true, true)
-			Expect(err).ToNot(HaveOccurred())
-
-			Expect(solution).To(ContainElement(A.IsFlagged(false)))
-
-			//	Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
-			Expect(len(solution)).To(Equal(1))
-		})
-
-		It("Uninstalls complex packages not in world correctly", func() {
-			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
-
-			for _, p := range []pkg.Package{B, C, D} {
-				_, err := dbDefinitions.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbInstalled.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-			solution, err := s.Uninstall(A, true, true)
-			Expect(err).ToNot(HaveOccurred())
-
-			Expect(solution).To(ContainElement(A.IsFlagged(false)))
-
-			Expect(len(solution)).To(Equal(1))
-		})
-
-		It("Uninstalls complex packages correctly, even if shared deps are required by system packages", func() {
-			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
-			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
-
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbDefinitions.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbInstalled.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-			solution, err := s.Uninstall(A, true, true)
-			Expect(err).ToNot(HaveOccurred())
-
-			Expect(solution).To(ContainElement(A.IsFlagged(false)))
-			Expect(solution).ToNot(ContainElement(B.IsFlagged(false)))
-
-			Expect(len(solution)).To(Equal(1))
-		})
-
-		It("Uninstalls complex packages in world correctly", func() {
-			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{C}, []*pkg.DefaultPackage{})
-
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbDefinitions.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-
-			for _, p := range []pkg.Package{A, C, D} {
-				_, err := dbInstalled.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-
-			solution, err := s.Uninstall(A, true, true)
-			Expect(err).ToNot(HaveOccurred())
-
-			Expect(solution).To(ContainElement(A.IsFlagged(false)))
-			Expect(solution).To(ContainElement(C.IsFlagged(false)))
-
-			Expect(len(solution)).To(Equal(2))
-		})
-
-		It("Uninstalls complex package correctly", func() {
-			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
-			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{D}, []*pkg.DefaultPackage{})
-			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
-			//	C // installed
-
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbDefinitions.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-
-			for _, p := range []pkg.Package{A, B, C, D} {
-				_, err := dbInstalled.CreatePackage(p)
-				Expect(err).ToNot(HaveOccurred())
-			}
-
-			solution, err := s.Uninstall(A, true, true)
-			Expect(err).ToNot(HaveOccurred())
-
-			Expect(solution).To(ContainElement(A.IsFlagged(false)))
-			Expect(solution).To(ContainElement(B.IsFlagged(false)))
-			Expect(solution).To(ContainElement(D.IsFlagged(false)))
-
-			Expect(len(solution)).To(Equal(3))
-
-		})
-
 	})
 
 	Context("Conflict set", func() {
@@ -1058,5 +1242,30 @@ var _ = Describe("Solver", func() {
 			Expect(len(solution)).To(Equal(3))
 
 		})
+
+		It("UpgradeUniverse upgrades correctly", func() {
+			for _, p := range []pkg.Package{A1, B, C} {
+				_, err := dbDefinitions.CreatePackage(p)
+				Expect(err).ToNot(HaveOccurred())
+			}
+
+			for _, p := range []pkg.Package{A, B} {
+				_, err := dbInstalled.CreatePackage(p)
+				Expect(err).ToNot(HaveOccurred())
+			}
+			uninstall, solution, err := s.UpgradeUniverse(true)
+			Expect(err).ToNot(HaveOccurred())
+
+			Expect(len(uninstall)).To(Equal(1))
+			Expect(uninstall[0].GetName()).To(Equal("a"))
+			Expect(uninstall[0].GetVersion()).To(Equal("1.1"))
+
+			Expect(solution).To(ContainElement(PackageAssert{Package: A1, Value: true}))
+			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
+			Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: false}))
+			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: false}))
+
+			Expect(len(solution)).To(Equal(4))
+		})
 	})
 })