Incorporate lock split-up into integration branch

Conflicts: cmd/dep/testdata/harness_tests/init/case1/final/Gopkg.lock cmd/dep/testdata/harness_tests/init/case2/final/Gopkg.lock cmd/dep/testdata/harness_tests/remove/force/case1/final/Gopkg.lock cmd/dep/testdata/harness_tests/remove/specific/case1/final/Gopkg.lock cmd/dep/testdata/harness_tests/remove/specific/case2/final/Gopkg.lock cmd/dep/testdata/harness_tests/remove/unused/case1/final/Gopkg.lock cmd/dep/testdata/harness_tests/status/case1/dot/final/Gopkg.lock cmd/dep/testdata/harness_tests/status/case1/json/final/Gopkg.lock cmd/dep/testdata/harness_tests/status/case1/table/final/Gopkg.lock txn_writer_test.go
2017-05-22 14:07:20 -04:00 · 2017-05-22 14:07:20 -04:00 · f6c2b15106
--- a/cmd/dep/ensure.go
+++ b/cmd/dep/ensure.go
@ -162,7 +162,7 @@ func (cmd *ensureCommand) Run(ctx *dep.Ctx, args []string) error {
 		writeV = dep.VendorAlways
 	}

-	newLock := dep.LockFromInterface(solution)
+	newLock := dep.LockFromSolution(solution)
 	sw, err := dep.NewSafeWriter(nil, p.Lock, newLock, writeV)
 	if err != nil {
 		return err
--- a/cmd/dep/init.go
+++ b/cmd/dep/init.go
@ -184,7 +184,7 @@ func (cmd *initCommand) Run(ctx *dep.Ctx, args []string) error {
 		handleAllTheFailuresOfTheWorld(err)
 		return err
 	}
-	l = dep.LockFromInterface(soln)
+	l = dep.LockFromSolution(soln)

 	// Iterate through the new projects in solved lock and add them to manifest
 	// if direct deps and log feedback for all the new projects.
@ -217,7 +217,7 @@ func (cmd *initCommand) Run(ctx *dep.Ctx, args []string) error {
 		return errors.Wrap(err, "prepare solver")
 	}

-	l.Memo = s.HashInputs()
+	l.SolveMeta.Memo = s.HashInputs()

 	// Pass timestamp (yyyyMMddHHmmss format) as suffix to backup name.
 	vendorbak, err := dep.BackupVendor(vpath, time.Now().Format("20060102150405"))
--- a/cmd/dep/prune.go
+++ b/cmd/dep/prune.go
@ -68,7 +68,7 @@ func (cmd *pruneCommand) Run(ctx *dep.Ctx, args []string) error {
 		return errors.Wrap(err, "could not set up solver for input hashing")
 	}

-	if !bytes.Equal(s.HashInputs(), p.Lock.Memo) {
+	if !bytes.Equal(s.HashInputs(), p.Lock.SolveMeta.Memo) {
 		return fmt.Errorf("lock hash doesn't match")
 	}

--- a/cmd/dep/remove.go
+++ b/cmd/dep/remove.go
@ -176,7 +176,7 @@ func (cmd *removeCommand) Run(ctx *dep.Ctx, args []string) error {
 		return err
 	}

-	newLock := dep.LockFromInterface(soln)
+	newLock := dep.LockFromSolution(soln)

 	sw, err := dep.NewSafeWriter(nil, p.Lock, newLock, dep.VendorOnChanged)
 	if err != nil {
--- a/cmd/dep/status.go
+++ b/cmd/dep/status.go
@ -277,7 +277,7 @@ func runStatusAll(loggers *dep.Loggers, out outputter, p *dep.Project, sm gps.So
 	slp := p.Lock.Projects()
 	sort.Sort(dep.SortedLockedProjects(slp))

-	if bytes.Equal(s.HashInputs(), p.Lock.Memo) {
+	if bytes.Equal(s.HashInputs(), p.Lock.SolveMeta.Memo) {
 		// If these are equal, we're guaranteed that the lock is a transitively
 		// complete picture of all deps. That eliminates the need for at least
 		// some checks.
--- a/cmd/dep/testdata/harness_tests/ensure/empty/case1/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/ensure/empty/case1/final/Gopkg.lock
@ -1,7 +1,13 @@
-memo = "14b07b05e0f01051b03887ab2bf80b516bc5510ea92f75f76c894b1745d8850c"

 [[projects]]
  name = "github.com/sdboyer/deptest"
  packages = ["."]
  revision = "ff2948a2ac8f538c4ecd55962e919d1e13e74baf"
  version = "v1.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "14b07b05e0f01051b03887ab2bf80b516bc5510ea92f75f76c894b1745d8850c"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/ensure/empty/case2/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/ensure/empty/case2/final/Gopkg.lock
@ -1,7 +1,13 @@
-memo = "e7725ea56516a42a641aaaf5d48754258d9f3c59949cb8a0e8a21b1ab6e07179"

 [[projects]]
  name = "github.com/sdboyer/deptest"
  packages = ["."]
  revision = "ff2948a2ac8f538c4ecd55962e919d1e13e74baf"
  version = "v1.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "e7725ea56516a42a641aaaf5d48754258d9f3c59949cb8a0e8a21b1ab6e07179"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/ensure/empty/case3/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/ensure/empty/case3/final/Gopkg.lock
@ -1,7 +1,13 @@
-memo = "e5c16e09ed6f0a1a2b3cf472c34b7fd50861dd070e81d5e623f72e8173f0c065"

 [[projects]]
  branch = "master"
  name = "github.com/sdboyer/deptest"
  packages = ["."]
  revision = "3f4c3bea144e112a69bbe5d8d01c1b09a544253f"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "e5c16e09ed6f0a1a2b3cf472c34b7fd50861dd070e81d5e623f72e8173f0c065"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/ensure/override/case1/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/ensure/override/case1/final/Gopkg.lock
@ -1,7 +1,13 @@
-memo = "8bca9526e654e56e05d9075d1f33fa5b649bf6d58aa7d71ca39e7fbea8468e07"

 [[projects]]
  name = "github.com/sdboyer/deptest"
  packages = ["."]
  revision = "ff2948a2ac8f538c4ecd55962e919d1e13e74baf"
  version = "v1.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "8bca9526e654e56e05d9075d1f33fa5b649bf6d58aa7d71ca39e7fbea8468e07"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/ensure/pkg-errors/case1/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/ensure/pkg-errors/case1/final/Gopkg.lock
@ -1 +1,7 @@
-memo = "ab4fef131ee828e96ba67d31a7d690bd5f2f42040c6766b1b12fe856f87e0ff7"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "ab4fef131ee828e96ba67d31a7d690bd5f2f42040c6766b1b12fe856f87e0ff7"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/ensure/update/case1/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/ensure/update/case1/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"

 [[projects]]
  name = "github.com/sdboyer/deptest"
@ -11,3 +10,10 @@ memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
  packages = ["."]
  revision = "5c607206be5decd28e6263ffffdcee067266015e"
  version = "v2.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/init/case1/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/init/case1/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"

 [[projects]]
  name = "github.com/sdboyer/deptest"
@ -10,3 +9,10 @@ memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
  name = "github.com/sdboyer/deptestdos"
  packages = ["."]
  revision = "a0196baa11ea047dd65037287451d36b861b00ea"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/init/case2/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/init/case2/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "ced51326ad990b11098d8076d0f7d72d89eee1ba6e8dacc7bc73be05cddac438"

 [[projects]]
  name = "github.com/sdboyer/deptest"
@ -11,3 +10,10 @@ memo = "ced51326ad990b11098d8076d0f7d72d89eee1ba6e8dacc7bc73be05cddac438"
  packages = ["."]
  revision = "5c607206be5decd28e6263ffffdcee067266015e"
  version = "v2.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "ced51326ad990b11098d8076d0f7d72d89eee1ba6e8dacc7bc73be05cddac438"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/init/case3/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/init/case3/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "af9a783a5430dabcaaf44683c09e2b729e1c0d61f13bfdf6677c4fd0b41387ca"

 [[projects]]
  branch = "master"
@ -10,3 +9,10 @@ memo = "af9a783a5430dabcaaf44683c09e2b729e1c0d61f13bfdf6677c4fd0b41387ca"
  name = "github.com/sdboyer/deptestdos"
  packages = ["."]
  revision = "a0196baa11ea047dd65037287451d36b861b00ea"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "af9a783a5430dabcaaf44683c09e2b729e1c0d61f13bfdf6677c4fd0b41387ca"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/init/skip-hidden/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/init/skip-hidden/final/Gopkg.lock
@ -1,7 +1,13 @@
-memo = "14b07b05e0f01051b03887ab2bf80b516bc5510ea92f75f76c894b1745d8850c"

 [[projects]]
  name = "github.com/sdboyer/deptest"
  packages = ["."]
  revision = "ff2948a2ac8f538c4ecd55962e919d1e13e74baf"
  version = "v1.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "14b07b05e0f01051b03887ab2bf80b516bc5510ea92f75f76c894b1745d8850c"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/remove/force/case1/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/remove/force/case1/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"

 [[projects]]
  name = "github.com/sdboyer/deptest"
@ -11,3 +10,10 @@ memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
  packages = ["."]
  revision = "5c607206be5decd28e6263ffffdcee067266015e"
  version = "v2.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/remove/specific/case1/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/remove/specific/case1/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "722f8e1427ab6d4dd1bc92376e4ce41ba6034a74e283a3fe4d65c7c838c7e0d2"

 [[projects]]
  name = "github.com/sdboyer/deptest"
@ -10,3 +9,10 @@ memo = "722f8e1427ab6d4dd1bc92376e4ce41ba6034a74e283a3fe4d65c7c838c7e0d2"
  name = "github.com/sdboyer/deptestdos"
  packages = ["."]
  revision = "a0196baa11ea047dd65037287451d36b861b00ea"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "722f8e1427ab6d4dd1bc92376e4ce41ba6034a74e283a3fe4d65c7c838c7e0d2"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/remove/specific/case2/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/remove/specific/case2/final/Gopkg.lock
@ -1,7 +1,13 @@
-memo = "e7725ea56516a42a641aaaf5d48754258d9f3c59949cb8a0e8a21b1ab6e07179"

 [[projects]]
  name = "github.com/sdboyer/deptest"
  packages = ["."]
  revision = "ff2948a2ac8f538c4ecd55962e919d1e13e74baf"
  version = "v1.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "e7725ea56516a42a641aaaf5d48754258d9f3c59949cb8a0e8a21b1ab6e07179"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/remove/unused/case1/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/remove/unused/case1/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "722f8e1427ab6d4dd1bc92376e4ce41ba6034a74e283a3fe4d65c7c838c7e0d2"

 [[projects]]
  name = "github.com/sdboyer/deptest"
@ -10,3 +9,10 @@ memo = "722f8e1427ab6d4dd1bc92376e4ce41ba6034a74e283a3fe4d65c7c838c7e0d2"
  name = "github.com/sdboyer/deptestdos"
  packages = ["."]
  revision = "a0196baa11ea047dd65037287451d36b861b00ea"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "722f8e1427ab6d4dd1bc92376e4ce41ba6034a74e283a3fe4d65c7c838c7e0d2"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/status/case1/dot/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/status/case1/dot/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"

 [[projects]]
  name = "github.com/sdboyer/deptest"
@ -11,3 +10,10 @@ memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
  packages = ["."]
  revision = "5c607206be5decd28e6263ffffdcee067266015e"
  version = "v2.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/status/case1/json/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/status/case1/json/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"

 [[projects]]
  name = "github.com/sdboyer/deptest"
@ -11,3 +10,10 @@ memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
  packages = ["."]
  revision = "5c607206be5decd28e6263ffffdcee067266015e"
  version = "v2.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/cmd/dep/testdata/harness_tests/status/case1/table/final/Gopkg.lock
+++ b/cmd/dep/testdata/harness_tests/status/case1/table/final/Gopkg.lock
@ -1,4 +1,3 @@
-memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"

 [[projects]]
  name = "github.com/sdboyer/deptest"
@ -11,3 +10,10 @@ memo = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
  packages = ["."]
  revision = "5c607206be5decd28e6263ffffdcee067266015e"
  version = "v2.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-hash = "1b381263a360eafafe3ef7f9be626672668d17250a3c9a8debd169d1b5e2eebb"
+  solver-name = "gps-cdcl"
+  solver-version = 1
--- a/internal/gps/result.go
+++ b/internal/gps/result.go
@ -14,6 +14,14 @@ import (
 // additional methods that report information about the solve run.
 type Solution interface {
 	Lock
+	// The name of the ProjectAnalyzer used in generating this solution.
+	AnalyzerName() string
+	// The version of the ProjectAnalyzer used in generating this solution.
+	AnalyzerVersion() int
+	// The name of the Solver used in generating this solution.
+	SolverName() string
+	// The version of the Solver used in generating this solution.
+	SolverVersion() int
 	Attempts() int
 }

@ -26,6 +34,15 @@ type solution struct {

 	// The hash digest of the input opts
 	hd []byte
+
+	// The analyzer name
+	analyzerName string
+
+	// The analyzer version
+	analyzerVersion int
+
+	// The solver used in producing this solution
+	solv Solver
 }

 // WriteDepTree takes a basedir and a Lock, and exports all the projects
@ -76,3 +93,19 @@ func (r solution) Attempts() int {
 func (r solution) InputHash() []byte {
 	return r.hd
 }
+
+func (r solution) AnalyzerName() string {
+	return r.analyzerName
+}
+
+func (r solution) AnalyzerVersion() int {
+	return r.analyzerVersion
+}
+
+func (r solution) SolverName() string {
+	return r.solv.Name()
+}
+
+func (r solution) SolverVersion() int {
+	return r.solv.Version()
+}
--- a/internal/gps/result_test.go
+++ b/internal/gps/result_test.go
@ -35,6 +35,7 @@ func init() {
 			}, nil),
 		},
 	}
+	basicResult.analyzerName, basicResult.analyzerVersion = (naiveAnalyzer{}).Info()

 	// just in case something needs punishing, kubernetes is happy to oblige
 	kub = atom{
--- a/internal/gps/solver.go
+++ b/internal/gps/solver.go
@ -328,6 +328,49 @@ type Solver interface {
 	// Solve initiates a solving run. It will either complete successfully with
 	// a Solution, or fail with an informative error.
 	Solve() (Solution, error)
+
+	// Name returns a string identifying the particular solver backend.
+	//
+	// Different solvers likely have different invariants, and likely will not
+	// have identical possible result sets for any particular inputs; in some
+	// cases, they may even be disjoint.
+	Name() string
+
+	// Version returns an int indicating the version of the solver of the given
+	// Name(). Implementations should change their reported version ONLY when
+	// the logic is changed in such a way that substantially changes the result
+	// set that is possible for a substantial subset of likely inputs.
+	//
+	// "Substantial" is an imprecise term, and it is used intentionally. There
+	// are no easy, general ways of subdividing constraint solving problems such
+	// that one can know, a priori, the full impact that subtle algorithmic
+	// changes will have on possible result sets. Consequently, we have to fall
+	// back on coarser, intuition-based reasoning as to whether a change is
+	// large enough that it is likely to be broadly user-visible.
+	//
+	// This is acceptable, because this value is not used programmatically by
+	// the solver in any way. Rather, it is intend for implementing tools to
+	// use as a coarse signal to users about compatibility between their tool's
+	// version and the current data, typically via persistence to a Lock.
+	// Changes to the version number reported should be weighed between
+	// confusing teams by having two members' tools continuously rolling back
+	// each others' chosen Solutions for no apparent reason, and annoying teams
+	// by changing the number for changes so remote that warnings about solver
+	// version mismatches become meaningless.
+	//
+	// Err on the side of caution.
+	//
+	// Chronology is the only implication of the ordering - that lower version
+	// numbers were published before higher numbers.
+	Version() int
+}
+
+func (s *solver) Name() string {
+	return "gps-cdcl"
+}
+
+func (s *solver) Version() int {
+	return 1
 }

 // Solve attempts to find a dependency solution for the given project, as
@ -351,9 +394,10 @@ func (s *solver) Solve() (Solution, error) {
 	var soln solution
 	if err == nil {
 		soln = solution{
-			att: s.attempts,
+			att:  s.attempts,
+			solv: s,
 		}
-
+		soln.analyzerName, soln.analyzerVersion = s.rd.an.Info()
 		soln.hd = s.HashInputs()

 		// Convert ProjectAtoms into LockedProjects
--- a/lock.go
+++ b/lock.go
@ -18,13 +18,29 @@ import (
 const LockName = "Gopkg.lock"

 type Lock struct {
-	Memo []byte
-	P    []gps.LockedProject
+	SolveMeta SolveMeta
+	P         []gps.LockedProject
+}
+
+type SolveMeta struct {
+	Memo            []byte
+	AnalyzerName    string
+	AnalyzerVersion int
+	SolverName      string
+	SolverVersion   int
 }

 type rawLock struct {
-	Memo     string             `toml:"memo"`
-	Projects []rawLockedProject `toml:"projects"`
+	SolveMeta solveMeta          `toml:"solve-meta"`
+	Projects  []rawLockedProject `toml:"projects"`
+}
+
+type solveMeta struct {
+	Memo            string `toml:"inputs-hash"`
+	AnalyzerName    string `toml:"analyzer-name"`
+	AnalyzerVersion int    `toml:"analyzer-version"`
+	SolverName      string `toml:"solver-name"`
+	SolverVersion   int    `toml:"solver-version"`
 }

 type rawLockedProject struct {
@ -58,11 +74,16 @@ func fromRawLock(raw rawLock) (*Lock, error) {
 		P: make([]gps.LockedProject, len(raw.Projects)),
 	}

-	l.Memo, err = hex.DecodeString(raw.Memo)
+	l.SolveMeta.Memo, err = hex.DecodeString(raw.SolveMeta.Memo)
 	if err != nil {
 		return nil, errors.Errorf("invalid hash digest in lock's memo field")
 	}

+	l.SolveMeta.AnalyzerName = raw.SolveMeta.AnalyzerName
+	l.SolveMeta.AnalyzerVersion = raw.SolveMeta.AnalyzerVersion
+	l.SolveMeta.SolverName = raw.SolveMeta.SolverName
+	l.SolveMeta.SolverVersion = raw.SolveMeta.SolverVersion
+
 	for i, ld := range raw.Projects {
 		r := gps.Revision(ld.Revision)

@ -84,11 +105,12 @@ func fromRawLock(raw rawLock) (*Lock, error) {
 		}
 		l.P[i] = gps.NewLockedProject(id, v, ld.Packages)
 	}
+
 	return l, nil
 }

 func (l *Lock) InputHash() []byte {
-	return l.Memo
+	return l.SolveMeta.Memo
 }

 func (l *Lock) Projects() []gps.LockedProject {
@ -98,7 +120,13 @@ func (l *Lock) Projects() []gps.LockedProject {
 // toRaw converts the manifest into a representation suitable to write to the lock file
 func (l *Lock) toRaw() rawLock {
 	raw := rawLock{
-		Memo:     hex.EncodeToString(l.Memo),
+		SolveMeta: solveMeta{
+			Memo:            hex.EncodeToString(l.SolveMeta.Memo),
+			AnalyzerName:    l.SolveMeta.AnalyzerName,
+			AnalyzerVersion: l.SolveMeta.AnalyzerVersion,
+			SolverName:      l.SolveMeta.SolverName,
+			SolverVersion:   l.SolveMeta.SolverVersion,
+		},
 		Projects: make([]rawLockedProject, len(l.P)),
 	}

@ -129,29 +157,25 @@ func (l *Lock) MarshalTOML() ([]byte, error) {
 	return result, errors.Wrap(err, "Unable to marshal lock to TOML string")
 }

-// LockFromInterface converts an arbitrary gps.Lock to dep's representation of a
-// lock. If the input is already dep's *lock, the input is returned directly.
+// LockFromSolution converts a gps.Solution to dep's representation of a lock.
 //
 // Data is defensively copied wherever necessary to ensure the resulting *lock
 // shares no memory with the original lock.
-//
-// As gps.Solution is a superset of gps.Lock, this can also be used to convert
-// solutions to dep's lock format.
-func LockFromInterface(in gps.Lock) *Lock {
-	if in == nil {
-		return nil
-	} else if l, ok := in.(*Lock); ok {
-		return l
-	}
-
+func LockFromSolution(in gps.Solution) *Lock {
 	h, p := in.InputHash(), in.Projects()

 	l := &Lock{
-		Memo: make([]byte, len(h)),
-		P:    make([]gps.LockedProject, len(p)),
+		SolveMeta: SolveMeta{
+			Memo:            make([]byte, len(h)),
+			AnalyzerName:    in.AnalyzerName(),
+			AnalyzerVersion: in.AnalyzerVersion(),
+			SolverName:      in.SolverName(),
+			SolverVersion:   in.SolverVersion(),
+		},
+		P: make([]gps.LockedProject, len(p)),
 	}

-	copy(l.Memo, h)
+	copy(l.SolveMeta.Memo, h)
 	copy(l.P, p)
 	return l
 }
--- a/lock_test.go
+++ b/lock_test.go
@ -28,7 +28,9 @@ func TestReadLock(t *testing.T) {

 	b, _ := hex.DecodeString("2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e")
 	want := &Lock{
-		Memo: b,
+		SolveMeta: SolveMeta{
+			Memo: b,
+		},
 		P: []gps.LockedProject{
 			gps.NewLockedProject(
 				gps.ProjectIdentifier{ProjectRoot: gps.ProjectRoot("github.com/golang/dep/internal/gps")},
@ -52,7 +54,9 @@ func TestReadLock(t *testing.T) {

 	b, _ = hex.DecodeString("2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e")
 	want = &Lock{
-		Memo: b,
+		SolveMeta: SolveMeta{
+			Memo: b,
+		},
 		P: []gps.LockedProject{
 			gps.NewLockedProject(
 				gps.ProjectIdentifier{ProjectRoot: gps.ProjectRoot("github.com/golang/dep/internal/gps")},
@ -75,7 +79,9 @@ func TestWriteLock(t *testing.T) {
 	want := h.GetTestFileString(golden)
 	memo, _ := hex.DecodeString("2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e")
 	l := &Lock{
-		Memo: memo,
+		SolveMeta: SolveMeta{
+			Memo: memo,
+		},
 		P: []gps.LockedProject{
 			gps.NewLockedProject(
 				gps.ProjectIdentifier{ProjectRoot: gps.ProjectRoot("github.com/golang/dep/internal/gps")},
@ -104,7 +110,9 @@ func TestWriteLock(t *testing.T) {
 	want = h.GetTestFileString(golden)
 	memo, _ = hex.DecodeString("2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e")
 	l = &Lock{
-		Memo: memo,
+		SolveMeta: SolveMeta{
+			Memo: memo,
+		},
 		P: []gps.LockedProject{
 			gps.NewLockedProject(
 				gps.ProjectIdentifier{ProjectRoot: gps.ProjectRoot("github.com/golang/dep/internal/gps")},
--- a/testdata/lock/error0.toml
+++ b/testdata/lock/error0.toml
@ -1,4 +1,5 @@
-memo = "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"
+[solve-meta]
+inputs-hash = "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"

 [[projects]]
  name = "github.com/golang/dep/internal/gps"
--- a/testdata/lock/error1.toml
+++ b/testdata/lock/error1.toml
@ -1,7 +1,9 @@
-memo = "000aaa2a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"
-
 [[projects]]
  name = "github.com/golang/dep/internal/gps"
  branch = "master"
  revision = "d05d5aca9f895d19e9265839bffeadd74a2d2ecb"
  packages = ["."]
+
+[solve-meta]
+  inputs-hash = "000aaa2a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"
+
--- a/testdata/lock/error2.toml
+++ b/testdata/lock/error2.toml
@ -1,5 +1,7 @@
-memo = "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"
-
 [[projects]]
  name = "github.com/golang/dep/internal/gps"
  packages = ["."]
+
+[solve-meta]
+  inputs-hash = "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"
+
--- a/testdata/lock/golden0.toml
+++ b/testdata/lock/golden0.toml
@ -1,7 +1,13 @@
-memo = "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"

 [[projects]]
  branch = "master"
  name = "github.com/golang/dep/internal/gps"
  packages = ["."]
  revision = "d05d5aca9f895d19e9265839bffeadd74a2d2ecb"
+
+[solve-meta]
+  analyzer-name = ""
+  analyzer-version = 0
+  inputs-hash = "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"
+  solver-name = ""
+  solver-version = 0
--- a/testdata/lock/golden1.toml
+++ b/testdata/lock/golden1.toml
@ -1,7 +1,13 @@
-memo = "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"

 [[projects]]
  name = "github.com/golang/dep/internal/gps"
  packages = ["."]
  revision = "d05d5aca9f895d19e9265839bffeadd74a2d2ecb"
  version = "0.12.2"
+
+[solve-meta]
+  analyzer-name = ""
+  analyzer-version = 0
+  inputs-hash = "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"
+  solver-name = ""
+  solver-version = 0
--- a/testdata/txn_writer/expected_diff_output.txt
+++ b/testdata/txn_writer/expected_diff_output.txt
@ -1,5 +1,3 @@
-Memo: 595716d270828e763c811ef79c9c41f85b1d1bfbdfe85280036405c03772206c -> 2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e
-
 Add:
 [[projects]]
  name = "github.com/sdboyer/deptest"
--- a/testdata/txn_writer/expected_lock.toml
+++ b/testdata/txn_writer/expected_lock.toml
@ -1,7 +1,13 @@
-memo = "595716d270828e763c811ef79c9c41f85b1d1bfbdfe85280036405c03772206c"

 [[projects]]
  name = "github.com/sdboyer/dep-test"
  packages = ["."]
  revision = "2a3a211e171803acb82d1d5d42ceb53228f51751"
  version = "1.0.0"
+
+[solve-meta]
+  analyzer-name = ""
+  analyzer-version = 0
+  inputs-hash = "595716d270828e763c811ef79c9c41f85b1d1bfbdfe85280036405c03772206c"
+  solver-name = ""
+  solver-version = 0
--- a/testdata/txn_writer/original_lock.toml
+++ b/testdata/txn_writer/original_lock.toml
@ -1,4 +1,5 @@
-memo = "595716d270828e763c811ef79c9c41f85b1d1bfbdfe85280036405c03772206c"
+[solve-meta]
+  inputs-hash = "595716d270828e763c811ef79c9c41f85b1d1bfbdfe85280036405c03772206c"

 [[projects]]
  name = "github.com/foo/bar"
--- a/testdata/txn_writer/updated_lock.toml
+++ b/testdata/txn_writer/updated_lock.toml
@ -1,4 +1,5 @@
-memo = "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e"
+[solve-meta]
+  inputs-hash = "595716d270828e763c811ef79c9c41f85b1d1bfbdfe85280036405c03772206c"

 [[projects]]
  name = "github.com/foo/bar"
--- a/txn_writer_test.go
+++ b/txn_writer_test.go
@ -261,18 +261,18 @@ func TestSafeWriter_ModifiedLock(t *testing.T) {

 	originalLock := new(Lock)
 	*originalLock = *pc.Project.Lock
-	originalLock.Memo = []byte{} // zero out the input hash to ensure non-equivalency
+	originalLock.SolveMeta.Memo = []byte{} // zero out the input hash to ensure non-equivalency
 	sw, _ := NewSafeWriter(nil, originalLock, pc.Project.Lock, VendorOnChanged)

 	// Verify prepared actions
 	if sw.HasManifest() {
-		t.Fatal("Did not expect the payload to contain the manifest")
+		t.Fatal("Did not expect the manifest to be written")
 	}
 	if !sw.HasLock() {
-		t.Fatal("Expected the payload to contain the lock")
+		t.Fatal("Expected that the writer should plan to write the lock")
 	}
 	if !sw.writeVendor {
-		t.Fatal("Expected the payload to contain the vendor directory")
+		t.Fatal("Expected that the writer should plan to write the vendor directory")
 	}

 	// Write changes
@ -308,7 +308,7 @@ func TestSafeWriter_ModifiedLockSkipVendor(t *testing.T) {

 	originalLock := new(Lock)
 	*originalLock = *pc.Project.Lock
-	originalLock.Memo = []byte{} // zero out the input hash to ensure non-equivalency
+	originalLock.SolveMeta.Memo = []byte{} // zero out the input hash to ensure non-equivalency
 	sw, _ := NewSafeWriter(nil, originalLock, pc.Project.Lock, VendorNever)

 	// Verify prepared actions