lint: enable more linters

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

.golangci.yml

@@ -20,6 +20,9 @@ linters:
     - unused
     - varcheck
     - golint
+    - staticcheck
+    - typecheck
+    - structcheck
   disable-all: true
 
 issues:

cache/manager.go

@@ -141,10 +141,10 @@ func (cm *cacheManager) GetByBlob(ctx context.Context, desc ocispec.Descriptor,
 		return nil, err
 	}
 
-	for _, si := range sis {
-		ref, err := cm.get(ctx, si.ID(), opts...)
+	if len(sis) > 0 {
+		ref, err := cm.get(ctx, sis[0].ID(), opts...)
 		if err != nil && !IsNotFound(err) {
-			return nil, errors.Wrapf(err, "failed to get record %s by blobchainid", si.ID())
+			return nil, errors.Wrapf(err, "failed to get record %s by blobchainid", sis[0].ID())
 		}
 		if p != nil {
 			releaseParent = true
@@ -158,13 +158,12 @@ func (cm *cacheManager) GetByBlob(ctx context.Context, desc ocispec.Descriptor,
 	}
 
 	var link ImmutableRef
-	for _, si := range sis {
-		ref, err := cm.get(ctx, si.ID(), opts...)
+	if len(sis) > 0 {
+		ref, err := cm.get(ctx, sis[0].ID(), opts...)
 		if err != nil && !IsNotFound(err) {
-			return nil, errors.Wrapf(err, "failed to get record %s by chainid", si.ID())
+			return nil, errors.Wrapf(err, "failed to get record %s by chainid", sis[0].ID())
 		}
 		link = ref
-		break
 	}
 
 	id := identity.NewID()

cache/manager_test.go

@@ -443,13 +443,13 @@ func TestExtractOnMutable(t *testing.T) {
 	err = content.WriteBlob(ctx, co.cs, "ref2", bytes.NewBuffer(b2), desc2)
 	require.NoError(t, err)
 
-	snap2, err := cm.GetByBlob(ctx, desc2, snap)
+	_, err = cm.GetByBlob(ctx, desc2, snap)
 	require.Error(t, err)
 
 	err = snap.SetBlob(ctx, desc)
 	require.NoError(t, err)
 
-	snap2, err = cm.GetByBlob(ctx, desc2, snap)
+	snap2, err := cm.GetByBlob(ctx, desc2, snap)
 	require.NoError(t, err)
 
 	err = snap.Release(context.TODO())
@@ -930,7 +930,7 @@ func TestLazyCommit(t *testing.T) {
 	err = snap2.Release(ctx)
 	require.NoError(t, err)
 
-	active, err = cm.GetMutable(ctx, active.ID())
+	_, err = cm.GetMutable(ctx, active.ID())
 	require.Error(t, err)
 	require.Equal(t, true, errors.Is(err, errNotFound))
 }

client/llb/meta.go

@@ -155,7 +155,7 @@ func shlexf(str string, replace bool, v ...interface{}) StateOption {
 	}
 	return func(s State) State {
 		arg, err := shlex.Split(str)
-		if err != nil {
+		if err != nil { //nolint
 			// TODO: handle error
 		}
 		return args(arg...)(s)

cmd/buildctl/diskusage.go

@@ -129,8 +129,6 @@ func printSummary(tw *tabwriter.Writer, du []*client.UsageInfo) {
 		}
 	}
 
-	tw = tabwriter.NewWriter(os.Stdout, 1, 8, 1, '\t', 0)
-
 	if shared > 0 {
 		fmt.Fprintf(tw, "Shared:\t%.2f\n", units.Bytes(shared))
 		fmt.Fprintf(tw, "Private:\t%.2f\n", units.Bytes(total-shared))

frontend/dockerfile/instructions/bflag_test.go

@@ -68,7 +68,7 @@ func TestBuilderFlags(t *testing.T) {
 	// ---
 
 	bf = NewBFlags()
-	flStr1 = bf.AddString("str1", "HI")
+	bf.AddString("str1", "HI")
 	bf.Args = []string{"--str1"}
 
 	if err = bf.Parse(); err == nil {
@@ -150,7 +150,7 @@ func TestBuilderFlags(t *testing.T) {
 	// ---
 
 	bf = NewBFlags()
-	flBool1 = bf.AddBool("bool1", false)
+	bf.AddBool("bool1", false)
 	bf.Args = []string{"--bool1=false1"}
 
 	if err = bf.Parse(); err == nil {
@@ -160,7 +160,7 @@ func TestBuilderFlags(t *testing.T) {
 	// ---
 
 	bf = NewBFlags()
-	flBool1 = bf.AddBool("bool1", false)
+	bf.AddBool("bool1", false)
 	bf.Args = []string{"--bool2"}
 
 	if err = bf.Parse(); err == nil {

frontend/gateway/gateway.go

@@ -176,7 +176,7 @@ func (gf *gatewayFrontend) Solve(ctx context.Context, llbBridge frontend.Fronten
 	}
 
 	lbf, ctx, err := serveLLBBridgeForwarder(ctx, llbBridge, gf.workers, inputs, sid)
-	defer lbf.conn.Close()
+	defer lbf.conn.Close() //nolint
 	if err != nil {
 		return nil, err
 	}

hack/dockerfiles/lint.Dockerfile

@@ -4,5 +4,5 @@ FROM golang:1.13-alpine
 RUN apk add --no-cache gcc musl-dev
 RUN wget -O- -nv https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s v1.27.0
 WORKDIR /go/src/github.com/moby/buildkit
-RUN --mount=target=/go/src/github.com/moby/buildkit \
+RUN --mount=target=/go/src/github.com/moby/buildkit --mount=target=/root/.cache,type=cache \
   golangci-lint run

solver/bboltcachestorage/storage.go

@@ -233,12 +233,6 @@ func (s *Store) releaseHelper(tx *bolt.Tx, id, resultID string) error {
 		}
 	}
 
-	links := tx.Bucket([]byte(resultBucket))
-	if results == nil {
-		return nil
-	}
-	links = links.Bucket([]byte(id))
-
 	return s.emptyBranchWithParents(tx, []byte(id))
 }
 

util/pull/pull.go

@@ -144,7 +144,7 @@ func (p *Puller) Pull(ctx context.Context) (*Pulled, error) {
 	}
 	stopProgress()
 
-	var usedBlobs, unusedBlobs []ocispec.Descriptor
+	var usedBlobs []ocispec.Descriptor
 
 	if schema1Converter != nil {
 		ongoing.remove(p.desc) // Not left in the content store so this is sufficient.
@@ -174,10 +174,6 @@ func (p *Puller) Pull(ctx context.Context) (*Pulled, error) {
 		if err := images.Dispatch(ctx, images.Handlers(handlers...), nil, p.desc); err != nil {
 			return nil, err
 		}
-
-		for _, j := range allBlobs {
-			unusedBlobs = append(unusedBlobs, j)
-		}
 	} else {
 		for _, j := range ongoing.added {
 			usedBlobs = append(usedBlobs, j.Descriptor)
@@ -186,11 +182,9 @@ func (p *Puller) Pull(ctx context.Context) (*Pulled, error) {
 
 	// split all pulled data to layers and rest. layers remain roots and are deleted with snapshots. rest will be linked to layers.
 	var notLayerBlobs []ocispec.Descriptor
-	var layerBlobs []ocispec.Descriptor
 	for _, j := range usedBlobs {
 		switch j.MediaType {
 		case ocispec.MediaTypeImageLayer, images.MediaTypeDockerSchema2Layer, ocispec.MediaTypeImageLayerGzip, images.MediaTypeDockerSchema2LayerGzip, images.MediaTypeDockerSchema2LayerForeign, images.MediaTypeDockerSchema2LayerForeignGzip:
-			layerBlobs = append(layerBlobs, j)
 		default:
 			notLayerBlobs = append(notLayerBlobs, j)
 		}