From a9836df57c505f2635934ef6a17d61746bd837b0 Mon Sep 17 00:00:00 2001
From: sam boyer <tech@samboyer.org>
Date: Tue, 18 Oct 2016 00:39:37 -0400
Subject: [PATCH 1/2] Add basic Lock implementation

---
 lock.go      | 84 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 lock_test.go | 68 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 152 insertions(+)
 create mode 100644 lock.go
 create mode 100644 lock_test.go

diff --git a/lock.go b/lock.go
new file mode 100644
index 0000000000..05db30b321
--- /dev/null
+++ b/lock.go
@@ -0,0 +1,84 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"io"
+
+	"github.com/sdboyer/gps"
+)
+
+type Lock struct {
+	Memo []byte
+	P    []gps.LockedProject
+}
+
+type rawLock struct {
+	Memo string      `json:"memo"`
+	P    []lockedDep `json:"projects"`
+}
+
+type lockedDep struct {
+	Name       string   `json:"name"`
+	Version    string   `json:"version,omitempty"`
+	Branch     string   `json:"branch,omitempty"`
+	Revision   string   `json:"revision"`
+	Repository string   `json:"repo,omitempty"`
+	Packages   []string `json:"packages"`
+}
+
+func ReadLock(r io.Reader) (*Lock, error) {
+	rl := rawLock{}
+	err := json.NewDecoder(r).Decode(&rl)
+	if err != nil {
+		return nil, err
+	}
+
+	b, err := hex.DecodeString(rl.Memo)
+	if err != nil {
+		return nil, fmt.Errorf("invalid hash digest in lock's memo field")
+	}
+	l := &Lock{
+		Memo: b,
+		P:    make([]gps.LockedProject, len(rl.P)),
+	}
+
+	for k, ld := range rl.P {
+		r := gps.Revision(ld.Revision)
+
+		var v gps.Version
+		if ld.Version != "" {
+			if ld.Branch != "" {
+				return nil, fmt.Errorf("lock file specified both a branch (%s) and version (%s) for %s", ld.Branch, ld.Version, ld.Name)
+			}
+			v = gps.NewVersion(ld.Version).Is(r)
+		} else if ld.Branch != "" {
+			v = gps.NewBranch(ld.Branch).Is(r)
+		} else if r == "" {
+			return nil, fmt.Errorf("lock file has entry for %s, but specifies no version", ld.Name)
+		} else {
+			v = r
+		}
+
+		id := gps.ProjectIdentifier{
+			ProjectRoot: gps.ProjectRoot(ld.Name),
+			NetworkName: ld.Repository,
+		}
+		l.P[k] = gps.NewLockedProject(id, v, ld.Packages)
+	}
+
+	return l, nil
+}
+
+func (l *Lock) InputHash() []byte {
+	return l.Memo
+}
+
+func (l *Lock) Projects() []gps.LockedProject {
+	return l.P
+}
diff --git a/lock_test.go b/lock_test.go
new file mode 100644
index 0000000000..ddaa68f015
--- /dev/null
+++ b/lock_test.go
@@ -0,0 +1,68 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"encoding/hex"
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/sdboyer/gps"
+)
+
+func TestReadLock(t *testing.T) {
+	const le = `{
+    "memo": "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e",
+    "projects": [
+        {
+            "name": "github.com/sdboyer/gps",
+            "branch": "master",
+			"version": "v0.12.0",
+            "revision": "d05d5aca9f895d19e9265839bffeadd74a2d2ecb",
+            "packages": ["."]
+        }
+    ]
+}`
+	const lg = `{
+    "memo": "2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e",
+    "projects": [
+        {
+            "name": "github.com/sdboyer/gps",
+            "branch": "master",
+            "revision": "d05d5aca9f895d19e9265839bffeadd74a2d2ecb",
+            "packages": ["."]
+        }
+    ]
+}`
+
+	_, err := ReadLock(strings.NewReader(le))
+	if err == nil {
+		t.Error("Reading lock with invalid props should have caused error, but did not")
+	} else if !strings.Contains(err.Error(), "both a branch") {
+		t.Errorf("Unexpected error %q; expected multiple version error", err)
+	}
+
+	l, err := ReadLock(strings.NewReader(lg))
+	if err != nil {
+		t.Fatalf("Should have read Lock correctly, but got err %q", err)
+	}
+
+	b, _ := hex.DecodeString("2252a285ab27944a4d7adcba8dbd03980f59ba652f12db39fa93b927c345593e")
+	l2 := &Lock{
+		Memo: b,
+		P: []gps.LockedProject{
+			gps.NewLockedProject(
+				gps.ProjectIdentifier{ProjectRoot: gps.ProjectRoot("github.com/sdboyer/gps")},
+				gps.NewBranch("master").Is(gps.Revision("d05d5aca9f895d19e9265839bffeadd74a2d2ecb")),
+				[]string{"."},
+			),
+		},
+	}
+
+	if !reflect.DeepEqual(l, l2) {
+		t.Error("Valid lock did not parse as expected")
+	}
+}

From f5699901cfcbf8d1cc0bd1964ba725c96673b087 Mon Sep 17 00:00:00 2001
From: sam boyer <tech@samboyer.org>
Date: Tue, 18 Oct 2016 01:18:18 -0400
Subject: [PATCH 2/2] i is better than k for indexes

---
 lock.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lock.go b/lock.go
index 05db30b321..2b8fb9b652 100644
--- a/lock.go
+++ b/lock.go
@@ -48,7 +48,7 @@ func ReadLock(r io.Reader) (*Lock, error) {
 		P:    make([]gps.LockedProject, len(rl.P)),
 	}
 
-	for k, ld := range rl.P {
+	for i, ld := range rl.P {
 		r := gps.Revision(ld.Revision)
 
 		var v gps.Version
@@ -69,7 +69,7 @@ func ReadLock(r io.Reader) (*Lock, error) {
 			ProjectRoot: gps.ProjectRoot(ld.Name),
 			NetworkName: ld.Repository,
 		}
-		l.P[k] = gps.NewLockedProject(id, v, ld.Packages)
+		l.P[i] = gps.NewLockedProject(id, v, ld.Packages)
 	}
 
 	return l, nil