Implementation of all-matches functionality + tests

When performing an *aptly snapshot pull*, users might list dependency
versions that can potentially match multiple packages in the source
snapshot. However, the current implementation of the 'snapshot pull'
command only allows one package to be pulled from a snapshot at a time
for a given dependency.

The newly implemented all-matches flag allows users to pull all the
matching packages from a source snapshot, provided that they satisfy the
version requirements indicated by the dependencies.

The all-matches flag defaults to false and only produces the described
behaviour when it is explicitly set to true.

cmd/snapshot_pull.go

@@ -18,6 +18,7 @@ func aptlySnapshotPull(cmd *commander.Command, args []string) error {
 
 	noDeps := context.flags.Lookup("no-deps").Value.Get().(bool)
 	noRemove := context.flags.Lookup("no-remove").Value.Get().(bool)
+	allMatches := context.flags.Lookup("all-matches").Value.Get().(bool)
 
 	// Load <name> snapshot
 	snapshot, err := context.CollectionFactory().SnapshotCollection().ByName(args[0])
@@ -97,24 +98,30 @@ func aptlySnapshotPull(cmd *commander.Command, args []string) error {
 			dep := dependencies[i]
 
 			// Search for package that can satisfy dependencies
-			pkg := sourcePackageList.Search(dep)
-			if pkg == nil {
+			searchResults := sourcePackageList.Search(dep, allMatches)
+			if searchResults == nil {
 				context.Progress().ColoredPrintf("@y[!]@| @!Dependency %s can't be satisfied with source %s@|", &dep, source)
 				continue
 			}
 
 			if !noRemove {
 				// Remove all packages with the same name and architecture
-				for p := packageList.Search(deb.Dependency{Architecture: pkg.Architecture, Pkg: pkg.Name}); p != nil; {
-					packageList.Remove(p)
-					context.Progress().ColoredPrintf("@r[-]@| %s removed", p)
-					p = packageList.Search(deb.Dependency{Architecture: pkg.Architecture, Pkg: pkg.Name})
+				for _, pkg := range searchResults {
+					for pS := packageList.Search(deb.Dependency{Architecture: pkg.Architecture, Pkg: pkg.Name}, allMatches); pS != nil; {
+						for _, p := range pS {
+							packageList.Remove(p)
+							context.Progress().ColoredPrintf("@r[-]@| %s removed", p)
+						}
+						pS = packageList.Search(deb.Dependency{Architecture: pkg.Architecture, Pkg: pkg.Name}, allMatches)
+					}
 				}
 			}
 
 			// Add new discovered package
-			packageList.Add(pkg)
-			context.Progress().ColoredPrintf("@g[+]@| %s added", pkg)
+			for _, pkg := range searchResults {
+				packageList.Add(pkg)
+				context.Progress().ColoredPrintf("@g[+]@| %s added", pkg)
+			}
 
 			if noDeps {
 				continue
@@ -122,26 +129,28 @@ func aptlySnapshotPull(cmd *commander.Command, args []string) error {
 
 			// Find missing dependencies for single added package
 			pL := deb.NewPackageList()
-			pL.Add(pkg)
+			for _, pkg := range searchResults {
+				pL.Add(pkg)
 
-			var missing []deb.Dependency
-			missing, err = pL.VerifyDependencies(context.DependencyOptions(), []string{arch}, packageList, nil)
-			if err != nil {
-				context.Progress().ColoredPrintf("@y[!]@| @!Error while verifying dependencies for pkg %s: %s@|", pkg, err)
-			}
-
-			// Append missing dependencies to the list of dependencies to satisfy
-			for _, misDep := range missing {
-				found := false
-				for _, d := range dependencies {
-					if d == misDep {
-						found = true
-						break
-					}
+				var missing []deb.Dependency
+				missing, err = pL.VerifyDependencies(context.DependencyOptions(), []string{arch}, packageList, nil)
+				if err != nil {
+					context.Progress().ColoredPrintf("@y[!]@| @!Error while verifying dependencies for pkg %s: %s@|", pkg, err)
 				}
 
-				if !found {
-					dependencies = append(dependencies, misDep)
+				// Append missing dependencies to the list of dependencies to satisfy
+				for _, misDep := range missing {
+					found := false
+					for _, d := range dependencies {
+						if d == misDep {
+							found = true
+							break
+						}
+					}
+
+					if !found {
+						dependencies = append(dependencies, misDep)
+					}
 				}
 			}
 		}
@@ -186,6 +195,8 @@ Example:
 	cmd.Flag.Bool("dry-run", false, "don't create destination snapshot, just show what would be pulled")
 	cmd.Flag.Bool("no-deps", false, "don't process dependencies, just pull listed packages")
 	cmd.Flag.Bool("no-remove", false, "don't remove other package versions when pulling package")
+	cmd.Flag.Bool("all-matches", false, "pull all the packages that satisfy the dependency version requirements")
+
 
 	return cmd
 }

deb/list.go

@@ -263,7 +263,7 @@ func (l *PackageList) VerifyDependencies(options int, architectures []string, so
 						continue
 					}
 
-					if sources.Search(dep) == nil {
+					if sources.Search(dep, false) == nil {
 						variantsMissing = append(variantsMissing, dep)
 						missingCount++
 					} else {
@@ -326,29 +326,47 @@ func (l *PackageList) PrepareIndex() {
 }
 
 // Search searches package index for specified package
-func (l *PackageList) Search(dep Dependency) *Package {
+func (l *PackageList) Search(dep Dependency, allMatches bool) []*Package {
 	if !l.indexed {
 		panic("list not indexed, can't search")
 	}
 
+	searchResults := []*Package{}
+
 	if dep.Relation == VersionDontCare {
 		for _, p := range l.providesIndex[dep.Pkg] {
 			if p.MatchesArchitecture(dep.Architecture) {
-				return p
+				searchResults = append(searchResults, p)
+
+				if !allMatches {
+					break
+				}
 			}
 		}
+		if len(searchResults) != 0 {
+			return searchResults
+		}
 	}
 
 	i := sort.Search(len(l.packagesIndex), func(j int) bool { return l.packagesIndex[j].Name >= dep.Pkg })
 
 	for i < len(l.packagesIndex) && l.packagesIndex[i].Name == dep.Pkg {
 		p := l.packagesIndex[i]
-		if p.MatchesDependency(dep) {
-			return p
+		if p.MatchesDependency(dep, allMatches) {
+			searchResults = append(searchResults, p)
+
+			if !allMatches {
+				break
+			}
 		}
 
 		i++
 	}
+
+	if len(searchResults) != 0 {
+		return searchResults
+	}
+
 	return nil
 }
 
@@ -396,7 +414,7 @@ func (l *PackageList) Filter(queries []string, withDependencies bool, source *Pa
 
 		for i < len(l.packagesIndex) && l.packagesIndex[i].Name == dep.Pkg {
 			p := l.packagesIndex[i]
-			if p.MatchesDependency(dep) {
+			if p.MatchesDependency(dep, false) {
 				result.Add(p)
 			}
 			i++
@@ -423,11 +441,13 @@ func (l *PackageList) Filter(queries []string, withDependencies bool, source *Pa
 
 			// try to satisfy dependencies
 			for _, dep := range missing {
-				p := l.Search(dep)
-				if p != nil {
-					result.Add(p)
-					dependencySource.Add(p)
-					added++
+				searchResults := l.Search(dep, false)
+				if searchResults != nil {
+					for _, p := range searchResults {
+						result.Add(p)
+						dependencySource.Add(p)
+						added++
+					}
 				}
 			}
 		}

deb/list_test.go

@@ -7,6 +7,43 @@ import (
 	"strings"
 )
 
+type containsChecker struct {
+	*CheckerInfo
+}
+
+func (c *containsChecker) Check(params []interface{}, names []string) (result bool, error string) {
+	var (
+		pkgSlice1 []*Package
+		pkgSlice2 []*Package
+		ok        bool
+	)
+
+	pkgMap := make (map[*Package]bool)
+
+
+	pkgSlice1, ok = params[0].([]*Package)
+	if !ok {
+		return false, "The first parameter is not a Package slice"
+	}
+	pkgSlice2, ok = params[1].([]*Package)
+	if !ok {
+		return false, "The second parameter is not a Package slice"
+	}
+
+	for _, pkg := range pkgSlice2 {
+		pkgMap[pkg] = true
+	}
+
+	for _, pkg := range pkgSlice1 {
+		if _, ok := pkgMap[pkg]; !ok {
+			return false, ""
+		}
+	}
+	return true, ""
+}
+
+var Contains Checker = &containsChecker{&CheckerInfo{Name: "Contains", Params: []string{"Container", "Expected to contain"}}}
+
 type PackageListSuite struct {
 	// Simple list with "real" packages from stanzas
 	list                   *PackageList
@@ -14,8 +51,10 @@ type PackageListSuite struct {
 
 	// Mocked packages in list
 	packages       []*Package
+	packages2      []*Package
 	sourcePackages []*Package
 	il             *PackageList
+	il2            *PackageList
 }
 
 var _ = Suite(&PackageListSuite{})
@@ -60,6 +99,20 @@ func (s *PackageListSuite) SetUpTest(c *C) {
 	}
 	s.il.PrepareIndex()
 
+	s.il2 = NewPackageList()
+	s.packages2 = []*Package{
+		&Package{Name: "mailer", Version: "3.5.8", Architecture: "amd64", Source: "postfix (1.3)", Provides: []string{"mail-agent"}, deps: &PackageDependencies{}},
+		&Package{Name: "sendmail", Version: "1.0", Architecture: "amd64", Source: "postfix (1.3)", Provides: []string{"mail-agent"}, deps: &PackageDependencies{}},
+		&Package{Name: "app", Version: "1.1-bp1", Architecture: "amd64", deps: &PackageDependencies{PreDepends: []string{"dpkg (>= 1.6)"}, Depends: []string{"lib (>> 0.9)", "data (>= 1.0)"}}},
+		&Package{Name: "app", Version: "1.1-bp2", Architecture: "amd64", deps: &PackageDependencies{PreDepends: []string{"dpkg (>= 1.6)"}, Depends: []string{"lib (>> 0.9)", "data (>= 1.0)"}}},
+		&Package{Name: "app", Version: "1.2", Architecture: "amd64", deps: &PackageDependencies{PreDepends: []string{"dpkg (>= 1.6)"}, Depends: []string{"lib (>> 0.9) | libx (>= 1.5)", "data (>= 1.0) | mail-agent"}}},
+		&Package{Name: "app", Version: "3.0", Architecture: "amd64", deps: &PackageDependencies{PreDepends: []string{"dpkg >= 1.6)"}, Depends: []string{"lib (>> 0.9)", "data (>= 1.0)"}}},
+	}
+	for _, p := range s.packages2 {
+		s.il2.Add(p)
+	}
+	s.il2.PrepareIndex()
+
 	s.sourcePackages = []*Package{
 		&Package{Name: "postfix", Version: "1.3", Architecture: "source", SourceArchitecture: "any", IsSource: true, deps: &PackageDependencies{}},
 		&Package{Name: "app", Version: "1.1~bp1", Architecture: "source", SourceArchitecture: "any", IsSource: true, deps: &PackageDependencies{}},
@@ -196,28 +249,54 @@ func (s *PackageListSuite) TestAppend(c *C) {
 }
 
 func (s *PackageListSuite) TestSearch(c *C) {
-	c.Check(func() { s.list.Search(Dependency{Architecture: "i386", Pkg: "app"}) }, Panics, "list not indexed, can't search")
+	//allMatches = False
+	c.Check(func() { s.list.Search(Dependency{Architecture: "i386", Pkg: "app"}, false) }, Panics, "list not indexed, can't search")
 
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app"}), Equals, s.packages[3])
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "mail-agent"}), Equals, s.packages[4])
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "puppy"}), IsNil)
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app"}, false), DeepEquals, []*Package{s.packages[3]})
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "mail-agent"}, false), DeepEquals, []*Package{s.packages[4]})
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "puppy"}, false), IsNil)
 
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionEqual, Version: "1.1~bp1"}), Equals, s.packages[3])
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionEqual, Version: "1.1~bp2"}), IsNil)
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionEqual, Version: "1.1~bp1"}, false), DeepEquals, []*Package{s.packages[3]})
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionEqual, Version: "1.1~bp2"}, false), IsNil)
 
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLess, Version: "1.1"}), Equals, s.packages[3])
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLess, Version: "1.1~~"}), IsNil)
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLess, Version: "1.1"}, false), DeepEquals, []*Package{s.packages[3]})
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLess, Version: "1.1~~"}, false), IsNil)
 
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLessOrEqual, Version: "1.1"}), Equals, s.packages[3])
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLessOrEqual, Version: "1.1~bp1"}), Equals, s.packages[3])
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLessOrEqual, Version: "1.1~~"}), IsNil)
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLessOrEqual, Version: "1.1"}, false), DeepEquals, []*Package{s.packages[3]})
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLessOrEqual, Version: "1.1~bp1"}, false), DeepEquals, []*Package{s.packages[3]})
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionLessOrEqual, Version: "1.1~~"}, false), IsNil)
 
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreater, Version: "1.0"}), Equals, s.packages[3])
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreater, Version: "1.2"}), IsNil)
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreater, Version: "1.0"}, false), DeepEquals, []*Package{s.packages[3]})
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreater, Version: "1.2"}, false), IsNil)
+
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreaterOrEqual, Version: "1.0"}, false), DeepEquals, []*Package{s.packages[3]})
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreaterOrEqual, Version: "1.1~bp1"}, false), DeepEquals, []*Package{s.packages[3]})
+	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreaterOrEqual, Version: "1.2"}, false), IsNil)
+
+	// allMatches = True
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app"}, true), Contains, []*Package{s.packages2[2], s.packages2[3], s.packages2[4], s.packages2[5]})
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "mail-agent"}, true), Contains, []*Package{s.packages2[0], s.packages2[1]})
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "puppy"}, true), IsNil)
+
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionEqual, Version: "1.1"}, true), Contains, []*Package{s.packages2[2], s.packages2[3]})
+
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionEqual, Version: "1.1"}, true), Contains, []*Package{s.packages2[2], s.packages2[3]})
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionEqual, Version: "3"}, true), Contains, []*Package{s.packages2[5]})
+
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionLess, Version: "1.2"}, true), Contains, []*Package{s.packages2[2], s.packages2[3]})
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionLess, Version: "1.1~"}, true), IsNil)
+
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionLessOrEqual, Version: "1.2"}, true), Contains, []*Package{s.packages2[2], s.packages2[3], s.packages2[4]})
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionLessOrEqual, Version: "1.1-bp1"}, true), Contains, []*Package{s.packages2[2]})
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionLessOrEqual, Version: "1.0"}, true), IsNil)
+
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionGreater, Version: "1.1"}, true), Contains, []*Package{s.packages2[2], s.packages2[3], s.packages2[4], s.packages2[5]})
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionGreater, Version: "5.0"}, true), IsNil)
+
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionGreaterOrEqual, Version: "1.2"}, true), Contains, []*Package{s.packages2[4], s.packages2[5]})
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionGreaterOrEqual, Version: "1.1~bp1"}, true), Contains, []*Package{s.packages2[2], s.packages2[3], s.packages2[4], s.packages2[5]})
+	c.Check(s.il2.Search(Dependency{Architecture: "amd64", Pkg: "app", Relation: VersionGreaterOrEqual, Version: "5.0"}, true), IsNil)
 
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreaterOrEqual, Version: "1.0"}), Equals, s.packages[3])
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreaterOrEqual, Version: "1.1~bp1"}), Equals, s.packages[3])
-	c.Check(s.il.Search(Dependency{Architecture: "i386", Pkg: "app", Relation: VersionGreaterOrEqual, Version: "1.2"}), IsNil)
 }
 
 func (s *PackageListSuite) TestFilter(c *C) {

deb/package.go

@@ -198,7 +198,7 @@ func (p *Package) MatchesArchitecture(arch string) bool {
 }
 
 // MatchesDependency checks whether package matches specified dependency
-func (p *Package) MatchesDependency(dep Dependency) bool {
+func (p *Package) MatchesDependency(dep Dependency, allMatches bool) bool {
 	if dep.Pkg != p.Name {
 		return false
 	}
@@ -212,9 +212,15 @@ func (p *Package) MatchesDependency(dep Dependency) bool {
 	}
 
 	r := CompareVersions(p.Version, dep.Version)
+
 	switch dep.Relation {
 	case VersionEqual:
-		return r == 0
+		if allMatches {
+			rn := CompareVersions(p.Version, dep.NextVersion())
+			return r+rn == 0 || r == 0
+		} else {
+			return r == 0
+		}
 	case VersionLess:
 		return r < 0
 	case VersionGreater:

deb/package_test.go

@@ -172,38 +172,44 @@ func (s *PackageSuite) TestMatchesDependency(c *C) {
 	p := NewPackageFromControlFile(s.stanza)
 
 	// exact match
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionEqual, Version: "7.40-2"}), Equals, true)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionEqual, Version: "7.40-2"}, false), Equals, true)
+
+	// exact match, same version, no revision specified
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionEqual, Version: "7.40"}, false), Equals, false)
+
+	// non-exact match, same version, no revision specified
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionEqual, Version: "7.40"}, true), Equals, true)
 
 	// different name
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena", Architecture: "i386", Relation: VersionEqual, Version: "7.40-2"}), Equals, false)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena", Architecture: "i386", Relation: VersionEqual, Version: "7.40-2"}, false), Equals, false)
 
 	// different version
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionEqual, Version: "7.40-3"}), Equals, false)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionEqual, Version: "7.40-3"}, false), Equals, false)
 
 	// different arch
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "amd64", Relation: VersionEqual, Version: "7.40-2"}), Equals, false)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "amd64", Relation: VersionEqual, Version: "7.40-2"}, false), Equals, false)
 
 	// empty arch
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "", Relation: VersionEqual, Version: "7.40-2"}), Equals, true)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "", Relation: VersionEqual, Version: "7.40-2"}, false), Equals, true)
 
 	// version don't care
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionDontCare, Version: ""}), Equals, true)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionDontCare, Version: ""}, false), Equals, true)
 
 	// >
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionGreater, Version: "7.40-2"}), Equals, false)
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionGreater, Version: "7.40-1"}), Equals, true)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionGreater, Version: "7.40-2"}, false), Equals, false)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionGreater, Version: "7.40-1"}, false), Equals, true)
 
 	// <
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionLess, Version: "7.40-2"}), Equals, false)
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionLess, Version: "7.40-3"}), Equals, true)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionLess, Version: "7.40-2"}, false), Equals, false)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionLess, Version: "7.40-3"}, false), Equals, true)
 
 	// >=
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionGreaterOrEqual, Version: "7.40-2"}), Equals, true)
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionGreaterOrEqual, Version: "7.40-3"}), Equals, false)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionGreaterOrEqual, Version: "7.40-2"}, false), Equals, true)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionGreaterOrEqual, Version: "7.40-3"}, false), Equals, false)
 
 	// <=
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionLessOrEqual, Version: "7.40-2"}), Equals, true)
-	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionLessOrEqual, Version: "7.40-1"}), Equals, false)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionLessOrEqual, Version: "7.40-2"}, false), Equals, true)
+	c.Check(p.MatchesDependency(Dependency{Pkg: "alien-arena-common", Architecture: "i386", Relation: VersionLessOrEqual, Version: "7.40-1"}, false), Equals, false)
 }
 
 func (s *PackageSuite) TestGetDependencies(c *C) {

deb/version.go

@@ -188,6 +188,29 @@ type Dependency struct {
 	Architecture string
 }
 
+// NextVersion returns the next version of a dependency (eg. if d.Version = 1.9, it returns 1.10)
+func (d *Dependency) NextVersion() string {
+	l := len(d.Version)
+
+	if l == 0 {
+		return ""
+	}
+
+	i := l
+	for  i > 0  {
+		_, err := strconv.ParseUint(d.Version[i-1:l],10,0)
+		if err != nil { break }
+		i--
+	}
+
+	v, err := strconv.ParseUint(d.Version[i:l],10,0)
+	if err != nil {
+		return d.Version
+	}
+
+	return d.Version[0:i] + strconv.Itoa(int(v)+1)
+}
+
 // Hash calculates some predefined unique ID of Dependency
 func (d *Dependency) Hash() string {
 	return fmt.Sprintf("%s:%s:%d:%s", d.Architecture, d.Pkg, d.Relation, d.Version)

deb/version_test.go

@@ -217,3 +217,45 @@ func (s *VersionSuite) TestDependencyString(c *C) {
 	d.Architecture = "i386"
 	c.Check(d.String(), Equals, "dpkg [i386]")
 }
+
+func (s *VersionSuite) TestDependencyNextVersion(c *C){
+	d, _ := ParseDependency("dpkg(=1.7)")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "1.8")
+
+	d, _ = ParseDependency("dpkg(=1.9)")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "1.10")
+
+	d, _ = ParseDependency("dpkg(=9)")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "10")
+
+	d, _ = ParseDependency("dpkg(=9.909)")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "9.910")
+
+	d, _ = ParseDependency("dpkg(=9.0.9)")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "9.0.10")
+
+	d, _ = ParseDependency("dpkg(=9.0.100)")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "9.0.101")
+
+	d, _ = ParseDependency("dpkg(=9.0.0-209)")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "9.0.0-210")
+
+	d, _ = ParseDependency("dpkg(=9.0.0-209rel)")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "9.0.0-209rel")
+
+	d, _ = ParseDependency("dpkg(=9.0.0-rel219)")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "9.0.0-rel220")
+
+	d, _ = ParseDependency("dpkg")
+	d.Architecture = "i386"
+	c.Check(d.NextVersion(), Equals, "")
+}