luet/pkg/solver/solver_test.go

// Copyright © 2019 Ettore Di Giacinto <mudler@gentoo.org>
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, see <http://www.gnu.org/licenses/>.

package solver_test

import (
	pkg "github.com/mudler/luet/pkg/package"
	. "github.com/onsi/ginkgo"
	. "github.com/onsi/gomega"

	. "github.com/mudler/luet/pkg/solver"
)

var _ = Describe("Solver", func() {

	db := pkg.NewInMemoryDatabase(false)
	dbInstalled := pkg.NewInMemoryDatabase(false)
	dbDefinitions := pkg.NewInMemoryDatabase(false)
	s := NewSolver(dbInstalled, dbDefinitions, db)

	BeforeEach(func() {
		db = pkg.NewInMemoryDatabase(false)
		dbInstalled = pkg.NewInMemoryDatabase(false)
		dbDefinitions = pkg.NewInMemoryDatabase(false)
		s = NewSolver(dbInstalled, dbDefinitions, db)
	})
	Context("Simple set", func() {
		It("Solves correctly if the selected package has no requirements or conflicts and we have nothing installed yet", func() {

			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{A})
			Expect(err).ToNot(HaveOccurred())
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(len(solution)).To(Equal(1))
		})

		It("Solves correctly if the selected package has no requirements or conflicts and we have installed one package", func() {

			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{C} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{B})
			Expect(err).ToNot(HaveOccurred())
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
			Expect(len(solution)).To(Equal(2))
		})

		It("Solves correctly if the selected package to install has no requirement or conflicts, but in the world there is one with a requirement", func() {

			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{B}, []*pkg.DefaultPackage{})
			E := pkg.NewPackage("E", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C, D, E} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{E, C} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{A})
			Expect(err).ToNot(HaveOccurred())
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: E, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: false}))
			Expect(solution).To(ContainElement(PackageAssert{Package: D, Value: false}))

			Expect(len(solution)).To(Equal(5))
		})

		It("Solves correctly if the selected package to install has requirements", func() {

			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{D}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C, D} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{C} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{A})
			Expect(err).ToNot(HaveOccurred())
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: D, Value: true}))

			Expect(len(solution)).To(Equal(3))
		})

		It("Solves correctly", func() {

			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})
			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{C} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{A})
			Expect(err).ToNot(HaveOccurred())
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
			Expect(len(solution)).To(Equal(3))
		})
		It("Solves correctly more complex ones", 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{})

			for _, p := range []pkg.Package{A, B, C, D} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{C} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{A})
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: D, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
			Expect(len(solution)).To(Equal(4))
			Expect(err).ToNot(HaveOccurred())
		})

		It("Solves correctly more complex ones", func() {

			E := pkg.NewPackage("E", "", []*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{D}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C, D, E} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{A})
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: D, Value: true}))
			Expect(len(solution)).To(Equal(3))
			Expect(err).ToNot(HaveOccurred())
		})

		It("Solves deps with expansion", func() {

			E := pkg.NewPackage("E", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			B := pkg.NewPackage("B", "1.1", []*pkg.DefaultPackage{D}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{&pkg.DefaultPackage{Name: "B", Version: ">1.0"}}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C, D, E} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{A})
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: D, Value: true}))
			Expect(len(solution)).To(Equal(3))
			Expect(err).ToNot(HaveOccurred())
		})
		It("Solves deps with more expansion", func() {

			C := pkg.NewPackage("c", "", []*pkg.DefaultPackage{&pkg.DefaultPackage{Name: "a", Version: ">=1.0", Category: "test"}}, []*pkg.DefaultPackage{})
			C.SetCategory("test")
			B := pkg.NewPackage("b", "1.0", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			B.SetCategory("test")
			A := pkg.NewPackage("a", "1.1", []*pkg.DefaultPackage{&pkg.DefaultPackage{Name: "b", Version: "1.0", Category: "test"}}, []*pkg.DefaultPackage{})
			A.SetCategory("test")

			for _, p := range []pkg.Package{A, B, C} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{C})
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
			Expect(len(solution)).To(Equal(3))
			Expect(err).ToNot(HaveOccurred())
		})

		It("Solves deps with more expansion", func() {

			C := pkg.NewPackage("c", "1.5", []*pkg.DefaultPackage{&pkg.DefaultPackage{Name: "a", Version: ">=1.0", Category: "test"}}, []*pkg.DefaultPackage{})
			C.SetCategory("test")
			B := pkg.NewPackage("b", "1.0", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			B.SetCategory("test")
			A := pkg.NewPackage("a", "1.1", []*pkg.DefaultPackage{&pkg.DefaultPackage{Name: "b", Version: "1.0", Category: "test"}}, []*pkg.DefaultPackage{})
			A.SetCategory("test")

			for _, p := range []pkg.Package{A, B, C} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{&pkg.DefaultPackage{Name: "c", Version: ">1.0", Category: "test"}})
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
			Expect(len(solution)).To(Equal(3))
			Expect(err).ToNot(HaveOccurred())
		})
		It("Solves deps with more expansion", func() {

			E := pkg.NewPackage("E", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			D := pkg.NewPackage("D", "1.4", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			B := pkg.NewPackage("B", "1.1", []*pkg.DefaultPackage{&pkg.DefaultPackage{Name: "D", Version: ">=1.0"}}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{&pkg.DefaultPackage{Name: "B", Version: ">=1.0"}}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C, D, E} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			s = NewSolver(dbInstalled, dbDefinitions, db)

			solution, err := s.Install([]pkg.Package{A})
			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: D, Value: true}))
			Expect(len(solution)).To(Equal(3))
			Expect(err).ToNot(HaveOccurred())
		})
		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{})

			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)
			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 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"})
			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("Find conflicts", func() {

			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})

			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{A}, []*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())
			}

			val, err := s.ConflictsWithInstalled(A)
			Expect(err).ToNot(HaveOccurred())
			Expect(val).To(BeTrue())

		})

		It("Find nested conflicts", func() {

			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{D}, []*pkg.DefaultPackage{})

			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{A}, []*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())
			}

			val, err := s.ConflictsWithInstalled(D)
			Expect(err).ToNot(HaveOccurred())
			Expect(val).To(BeTrue())
		})

		It("Doesn't find nested conflicts", func() {

			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{D}, []*pkg.DefaultPackage{})

			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{A}, []*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())
			}

			val, err := s.ConflictsWithInstalled(C)
			Expect(err).ToNot(HaveOccurred())
			Expect(val).ToNot(BeTrue())
		})

		It("Doesn't find conflicts", func() {

			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})

			B := pkg.NewPackage("B", "", []*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())
			}
			val, err := s.ConflictsWithInstalled(C)
			Expect(err).ToNot(HaveOccurred())
			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)
			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)
			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)
			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)
			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)
			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() {

		It("is unsolvable - as we something we ask to install conflict with system stuff", func() {
			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			//	D := pkg.NewPackage("D", "", []pkg.Package{}, []pkg.Package{})
			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{C})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{C} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			solution, err := s.Install([]pkg.Package{A})
			Expect(len(solution)).To(Equal(0))
			Expect(err).To(HaveOccurred())
		})

	})

	Context("Complex data sets", func() {
		It("Solves them correctly", func() {
			C := pkg.NewPackage("C", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			E := pkg.NewPackage("E", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			F := pkg.NewPackage("F", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			G := pkg.NewPackage("G", "", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
			H := pkg.NewPackage("H", "", []*pkg.DefaultPackage{G}, []*pkg.DefaultPackage{})
			D := pkg.NewPackage("D", "", []*pkg.DefaultPackage{H}, []*pkg.DefaultPackage{})
			B := pkg.NewPackage("B", "", []*pkg.DefaultPackage{D}, []*pkg.DefaultPackage{})
			A := pkg.NewPackage("A", "", []*pkg.DefaultPackage{B}, []*pkg.DefaultPackage{})

			for _, p := range []pkg.Package{A, B, C, D, E, F, G} {
				_, err := dbDefinitions.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}

			for _, p := range []pkg.Package{C} {
				_, err := dbInstalled.CreatePackage(p)
				Expect(err).ToNot(HaveOccurred())
			}
			solution, err := s.Install([]pkg.Package{A})
			Expect(err).ToNot(HaveOccurred())

			Expect(solution).To(ContainElement(PackageAssert{Package: A, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: B, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: D, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: C, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: H, Value: true}))
			Expect(solution).To(ContainElement(PackageAssert{Package: G, Value: true}))

			Expect(len(solution)).To(Equal(6))
		})
	})

	Context("Selection", func() {
		a := pkg.NewPackage("A", ">=2.0", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
		a1 := pkg.NewPackage("A", "2.0", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
		a11 := pkg.NewPackage("A", "2.1", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
		a01 := pkg.NewPackage("A", "2.2", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
		a02 := pkg.NewPackage("A", "2.3", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
		a03 := pkg.NewPackage("A", "2.3.4", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})
		old := pkg.NewPackage("A", "1.3.1", []*pkg.DefaultPackage{}, []*pkg.DefaultPackage{})

		It("Expands correctly", func() {
			lst, err := a.Expand(&[]pkg.Package{a1, a11, a01, a02, a03, old})
			Expect(err).ToNot(HaveOccurred())
			Expect(lst).To(ContainElement(a11))
			Expect(lst).To(ContainElement(a1))
			Expect(lst).To(ContainElement(a01))
			Expect(lst).To(ContainElement(a02))
			Expect(lst).To(ContainElement(a03))
			Expect(lst).ToNot(ContainElement(old))
			Expect(len(lst)).To(Equal(5))
			p := pkg.Best(lst)
			Expect(p).To(Equal(a03))
		})
	})

})