First pass at a gb manifest importer

cmd/dep/gb_importer.go

@@ -122,8 +122,34 @@ func (i *gbImporter) buildProjectConstraint(pkg gbDependency) (pc gps.ProjectCon
 		return
 	}
 
+	/*
+		gb's vendor plugin (gb vendor), which manages the vendor tree and manifest
+		file, supports fetching by a specific tag or revision, but if you specify
+		either of those it's a detached checkout and the "branch" field is HEAD.
+		The only time the "branch" field is not "HEAD" is if you do not specify a
+		tag or revision, otherwise it's either "master" or the value of the -branch
+		flag
+
+		This means that, generally, the only possible "constraint" we can really specify is
+		the branch name if the branch name is not HEAD. Otherwise, it's a specific revision.
+
+		However, if we can infer a tag that points to the revision or the branch, we may be able
+		to use that as the constraint
+	*/
+
 	pc.Ident = gps.ProjectIdentifier{ProjectRoot: gps.ProjectRoot(pkg.Importpath), Source: pkg.Repository}
-	pc.Constraint, err = i.sm.InferConstraint(pkg.Revision, pc.Ident)
+
+	// The default constraint is just a revision
+	var revision = gps.Revision(pkg.Revision)
+
+	// See if we can get a version from that constraint
+	version, err := lookupVersionForLockedProject(pc.Ident, revision, revision, i.sm)
+	if err != nil {
+		return
+	}
+
+	// And now try to infer a constraint from the returned version
+	pc.Constraint, err = i.sm.InferConstraint(version.String(), pc.Ident)
 	if err != nil {
 		return
 	}

cmd/dep/gb_importer_test.go

@@ -0,0 +1,165 @@
+// Copyright 2017 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 (
+	"bytes"
+	"log"
+	"path/filepath"
+	"testing"
+
+	"github.com/golang/dep/internal/gps"
+	"github.com/golang/dep/internal/test"
+	"github.com/pkg/errors"
+)
+
+const testGbProjectRoot = "github.com/golang/notexist"
+
+func TestGbConfig_Import(t *testing.T) {
+	h := test.NewHelper(t)
+	defer h.Cleanup()
+
+	ctx := newTestContext(h)
+	sm, err := ctx.SourceManager()
+	h.Must(err)
+	defer sm.Release()
+
+	h.TempDir(filepath.Join("src", testGbProjectRoot, "vendor"))
+	h.TempCopy(filepath.Join(testGbProjectRoot, "vendor", "manifest"), "gb/manifest")
+	projectRoot := h.Path(testGbProjectRoot)
+
+	// Capture stderr so we can verify output
+	verboseOutput := &bytes.Buffer{}
+	ctx.Err = log.New(verboseOutput, "", 0)
+
+	g := newGbImporter(ctx.Err, false, sm) // Disable verbose so that we don't print values that change each test run
+	if !g.HasDepMetadata(projectRoot) {
+		t.Fatal("Expected the importer to detect the gb manifest file")
+	}
+
+	m, l, err := g.Import(projectRoot, testGbProjectRoot)
+	h.Must(err)
+
+	if m == nil {
+		t.Fatal("Expected the manifest to be generated")
+	}
+
+	if l == nil {
+		t.Fatal("Expected the lock to be generated")
+	}
+
+	goldenFile := "gb/golden.txt"
+	got := verboseOutput.String()
+	want := h.GetTestFileString(goldenFile)
+	if want != got {
+		if *test.UpdateGolden {
+			if err := h.WriteTestFile(goldenFile, got); err != nil {
+				t.Fatalf("%+v", errors.Wrapf(err, "Unable to write updated golden file %s", goldenFile))
+			}
+		} else {
+			t.Fatalf("expected %s, got %s", want, got)
+		}
+	}
+}
+
+func TestGbConfig_Convert_Project(t *testing.T) {
+	h := test.NewHelper(t)
+	defer h.Cleanup()
+
+	ctx := newTestContext(h)
+	sm, err := ctx.SourceManager()
+	h.Must(err)
+	defer sm.Release()
+
+	pkg := "github.com/sdboyer/deptest"
+	repo := "https://github.com/sdboyer/deptest.git"
+
+	g := newGbImporter(ctx.Err, true, sm)
+	g.manifest = gbManifest{
+		Dependencies: []gbDependency{
+			{
+				Importpath: pkg,
+				Repository: repo,
+				Revision:   "ff2948a2ac8f538c4ecd55962e919d1e13e74baf",
+			},
+		},
+	}
+
+	manifest, lock, err := g.convert(testGbProjectRoot)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	d, ok := manifest.Constraints[gps.ProjectRoot(pkg)]
+	if !ok {
+		t.Fatal("Expected the manifest to have a dependency for 'github.com/sdboyer/deptest' but got none")
+	}
+
+	wantC := "^1.0.0"
+	gotC := d.Constraint.String()
+	if gotC != wantC {
+		t.Fatalf("Expected manifest constraint to be %s, got %s", wantC, gotC)
+	}
+
+	gotS := d.Source
+	if gotS != repo {
+		t.Fatalf("Expected manifest source to be %s, got %s", repo, gotS)
+	}
+
+	wantP := 1
+	gotP := len(lock.P)
+	if gotP != 1 {
+		t.Fatalf("Expected the lock to contain %d project but got %d", wantP, gotP)
+	}
+
+	p := lock.P[0]
+	gotPr := string(p.Ident().ProjectRoot)
+	if gotPr != pkg {
+		t.Fatalf("Expected the lock to have a project for %s but got '%s'", pkg, gotPr)
+	}
+
+	gotS = p.Ident().Source
+	if gotS != repo {
+		t.Fatalf("Expected locked source to be %s, got '%s'", repo, gotS)
+	}
+
+	lv := p.Version()
+	lpv, ok := lv.(gps.PairedVersion)
+	if !ok {
+		t.Fatalf("Expected locked version to be a PairedVersion but got %T", lv)
+	}
+
+	wantRev := "ff2948a2ac8f538c4ecd55962e919d1e13e74baf"
+	gotRev := lpv.Revision().String()
+	if gotRev != wantRev {
+		t.Fatalf("Expected locked revision to be %s, got %s", wantRev, gotRev)
+	}
+
+	wantV := "v1.0.0"
+	gotV := lpv.String()
+	if gotV != wantV {
+		t.Fatalf("Expected locked version to be %s, got %s", wantV, gotV)
+	}
+}
+
+func TestGbConfig_Convert_BadInput_EmptyPackageName(t *testing.T) {
+	h := test.NewHelper(t)
+	defer h.Cleanup()
+
+	ctx := newTestContext(h)
+	sm, err := ctx.SourceManager()
+	h.Must(err)
+	defer sm.Release()
+
+	g := newGbImporter(ctx.Err, true, sm)
+	g.manifest = gbManifest{
+		Dependencies: []gbDependency{{Importpath: ""}},
+	}
+
+	_, _, err = g.convert(testGbProjectRoot)
+	if err == nil {
+		t.Fatal("Expected conversion to fail because the package name is empty")
+	}
+}

cmd/dep/testdata/gb/golden.txt

@@ -0,0 +1,7 @@
+Detected gb manifest file...
+Converting from gb manifest...
+  Using master as initial constraint for imported dep github.com/kr/fs
+  Trying master (2788f0d) as initial lock for imported dep github.com/kr/fs
+  Using f234c3c6540c0358b1802f7fd90c0879af9232eb as initial hint for imported dep github.com/pkg/sftp
+  Using ^1.0.0 as initial constraint for imported dep github.com/sdboyer/deptest
+  Trying v1.0.0 (ff2948a) as initial lock for imported dep github.com/sdboyer/deptest

cmd/dep/testdata/gb/manifest

@@ -0,0 +1,25 @@
+{
+	"version": 0,
+	"dependencies": [
+		{
+			"importpath": "github.com/kr/fs",
+			"repository": "https://github.com/kr/fs",
+			"revision": "2788f0dbd16903de03cb8186e5c7d97b69ad387b",
+			"branch": "master",
+			"path": ""
+		},
+		{
+			"importpath": "github.com/pkg/sftp",
+			"repository": "https://github.com/pkg/sftp",
+			"revision": "f234c3c6540c0358b1802f7fd90c0879af9232eb",
+			"branch": "master",
+			"path": ""
+		},
+		{
+			"importpath": "github.com/sdboyer/deptest",
+			"repository": "https://github.com/sdboyer/deptest",
+			"revision": "ff2948a2ac8f538c4ecd55962e919d1e13e74baf",
+			"branch": "HEAD"
+		}
+	]
+}