Inlining afero fs to goget call, and new go getfetcher

pkg/download/goget/goget.go

@@ -25,22 +25,19 @@ import (
 func New() (download.Protocol, error) {
 	const op errors.Op = "goget.New"
 	goBin := env.GoBinPath()
-	fs := afero.NewOsFs()
-	mf, err := module.NewGoGetFetcher(goBin, fs)
+	mf, err := module.NewGoGetFetcher(goBin)
 	if err != nil {
 		return nil, errors.E(op, err)
 	}
 	return &goget{
 		goBinPath: goBin,
 		fetcher:   mf,
-		fs:        fs,
 	}, nil
 }
 
 type goget struct {
 	goBinPath string
 	fetcher   module.Fetcher
-	fs        afero.Fs
 }
 
 func (gg *goget) List(ctx context.Context, mod string) ([]string, error) {
@@ -91,12 +88,13 @@ func (gg *goget) Latest(ctx context.Context, mod string) (*storage.RevInfo, erro
 }
 
 func (gg *goget) list(op errors.Op, mod string) (*listResp, error) {
-	hackyPath, err := afero.TempDir(gg.fs, "", "hackymod")
+	fs := afero.NewOsFs()
+	hackyPath, err := afero.TempDir(fs, "", "hackymod")
 	if err != nil {
 		return nil, errors.E(op, err)
 	}
-	defer gg.fs.RemoveAll(hackyPath)
-	err = module.Dummy(gg.fs, hackyPath)
+	defer fs.RemoveAll(hackyPath)
+	err = module.Dummy(fs, hackyPath)
 	cmd := exec.Command(
 		gg.goBinPath,
 		"list", "-m", "-versions", "-json",

pkg/module/go_get_fetcher.go

@@ -19,13 +19,13 @@ type goGetFetcher struct {
 }
 
 // NewGoGetFetcher creates fetcher which uses go get tool to fetch modules
-func NewGoGetFetcher(goBinaryName string, fs afero.Fs) (Fetcher, error) {
+func NewGoGetFetcher(goBinaryName string) (Fetcher, error) {
 	const op errors.Op = "module.NewGoGetFetcher"
 	if err := validGoBinary(goBinaryName); err != nil {
 		return nil, errors.E(op, err)
 	}
 	return &goGetFetcher{
-		fs:           fs,
+		fs:           afero.NewOsFs(),
 		goBinaryName: goBinaryName,
 	}, nil
 }

pkg/module/go_get_fetcher_test.go

@@ -6,20 +6,18 @@ import (
 
 	"github.com/gomods/athens/pkg/config/env"
 	"github.com/stretchr/testify/assert"
-
-	"github.com/spf13/afero"
 )
 
 func (s *ModuleSuite) TestNewGoGetFetcher() {
 	r := s.Require()
-	fetcher, err := NewGoGetFetcher(s.goBinaryName, s.fs)
+	fetcher, err := NewGoGetFetcher(s.goBinaryName)
 	r.NoError(err)
 	_, ok := fetcher.(*goGetFetcher)
 	r.True(ok)
 }
 
 func (s *ModuleSuite) TestGoGetFetcherError() {
-	fetcher, err := NewGoGetFetcher("invalidpath", afero.NewOsFs())
+	fetcher, err := NewGoGetFetcher("invalidpath")
 
 	assert.Nil(s.T(), fetcher)
 	assert.EqualError(s.T(), err, "exec: \"invalidpath\": executable file not found in $PATH")
@@ -29,7 +27,7 @@ func (s *ModuleSuite) TestGoGetFetcherFetch() {
 	r := s.Require()
 	// we need to use an OS filesystem because fetch executes vgo on the command line, which
 	// always writes to the filesystem
-	fetcher, err := NewGoGetFetcher(s.goBinaryName, afero.NewOsFs())
+	fetcher, err := NewGoGetFetcher(s.goBinaryName)
 	r.NoError(err)
 	ref, err := fetcher.Fetch(repoURI, version)
 	r.NoError(err, "fetch shouldn't error")
@@ -56,7 +54,7 @@ func ExampleFetch() {
 	repoURI := "github.com/arschles/assert"
 	version := "v1.0.0"
 	goBinaryName := env.GoBinPath()
-	fetcher, err := NewGoGetFetcher(goBinaryName, afero.NewOsFs())
+	fetcher, err := NewGoGetFetcher(goBinaryName)
 	ref, err := fetcher.Fetch(repoURI, version)
 	// handle errors if any
 	if err != nil {