Merge pull request #4191 from nalind/cause

Drop util/util.Cause()

cmd/buildah/main.go

@@ -14,7 +14,6 @@ import (
 	"github.com/containers/buildah/define"
 	"github.com/containers/buildah/pkg/cli"
 	"github.com/containers/buildah/pkg/parse"
-	"github.com/containers/buildah/util"
 	"github.com/containers/common/pkg/config"
 	"github.com/containers/storage"
 	"github.com/containers/storage/pkg/unshare"
@@ -238,7 +237,8 @@ func main() {
 			fmt.Fprintf(os.Stderr, "%v\n", err)
 		}
 		exitCode := cli.ExecErrorCodeGeneric
-		if ee, ok := (util.Cause(err)).(*exec.ExitError); ok {
+		var ee *exec.ExitError
+		if errors.As(err, &ee) {
 			if w, ok := ee.Sys().(syscall.WaitStatus); ok {
 				exitCode = w.ExitStatus()
 			}

copier/copier_test.go

@@ -22,7 +22,6 @@ import (
 	"testing"
 	"time"
 
-	"github.com/containers/buildah/util"
 	"github.com/containers/storage/pkg/idtools"
 	"github.com/containers/storage/pkg/reexec"
 	"github.com/sirupsen/logrus"
@@ -556,7 +555,7 @@ func testPut(t *testing.T) {
 				defer os.RemoveAll(tmp)
 				err = Put(tmp, tmp, PutOptions{UIDMap: uidMap, GIDMap: gidMap, NoOverwriteDirNonDir: !overwrite}, bytes.NewReader(archive))
 				if overwrite {
-					if util.Cause(err) != syscall.EPERM {
+					if !errors.Is(err, syscall.EPERM) {
 						assert.Nilf(t, err, "expected to overwrite directory with type %c: %v", typeFlag, err)
 					}
 				} else {
@@ -584,7 +583,7 @@ func testPut(t *testing.T) {
 				defer os.RemoveAll(tmp)
 				err = Put(tmp, tmp, PutOptions{UIDMap: uidMap, GIDMap: gidMap, NoOverwriteNonDirDir: !overwrite}, bytes.NewReader(archive))
 				if overwrite {
-					if util.Cause(err) != syscall.EPERM {
+					if !errors.Is(err, syscall.EPERM) {
 						assert.Nilf(t, err, "expected to overwrite file with type %c: %v", typeFlag, err)
 					}
 				} else {
@@ -660,7 +659,7 @@ func isExpectedError(err error, inSubdir bool, name string, expectedErrors []exp
 		if expectedError.name != name {
 			continue
 		}
-		if !strings.Contains(util.Cause(err).Error(), util.Cause(expectedError.err).Error()) {
+		if !strings.Contains(err.Error(), expectedError.err.Error()) {
 			// not expecting this specific error
 			continue
 		}

copier/xattrs.go

@@ -4,12 +4,12 @@
 package copier
 
 import (
+	"errors"
 	"fmt"
 	"path/filepath"
 	"strings"
 	"syscall"
 
-	"github.com/containers/buildah/util"
 	"golang.org/x/sys/unix"
 )
 
@@ -45,11 +45,11 @@ func Lgetxattrs(path string) (map[string]string, error) {
 		list = make([]byte, listSize)
 		size, err := unix.Llistxattr(path, list)
 		if err != nil {
-			if util.Cause(err) == syscall.ERANGE {
+			if errors.Is(err, syscall.ERANGE) {
 				listSize *= 2
 				continue
 			}
-			if (util.Cause(err) == syscall.ENOTSUP) || (util.Cause(err) == syscall.ENOSYS) {
+			if errors.Is(err, syscall.ENOTSUP) || errors.Is(err, syscall.ENOSYS) {
 				// treat these errors listing xattrs as equivalent to "no xattrs"
 				list = list[:0]
 				break
@@ -71,7 +71,7 @@ func Lgetxattrs(path string) (map[string]string, error) {
 				attributeValue = make([]byte, attributeSize)
 				size, err := unix.Lgetxattr(path, attribute, attributeValue)
 				if err != nil {
-					if util.Cause(err) == syscall.ERANGE {
+					if errors.Is(err, syscall.ERANGE) {
 						attributeSize *= 2
 						continue
 					}

copier/xattrs_test.go

@@ -1,13 +1,13 @@
 package copier
 
 import (
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"syscall"
 	"testing"
 
-	"github.com/containers/buildah/util"
 	"github.com/stretchr/testify/assert"
 )
 
@@ -39,7 +39,7 @@ func TestXattrs(t *testing.T) {
 			defer os.Remove(f.Name())
 
 			err = Lsetxattrs(f.Name(), map[string]string{attribute: value})
-			if util.Cause(err) == syscall.ENOTSUP {
+			if errors.Is(err, syscall.ENOTSUP) {
 				t.Skipf("extended attributes not supported on %q, skipping", tmp)
 			}
 			if !assert.Nil(t, err, "error setting attribute on file: %v", err) {

util/util.go

@@ -466,22 +466,3 @@ func VerifyTagName(imageSpec string) (types.ImageReference, error) {
 	}
 	return ref, nil
 }
-
-// Cause returns the most underlying error for the provided one. There is a
-// maximum error depth of 100 to avoid endless loops. An additional error log
-// message will be created if this maximum has reached.
-func Cause(err error) (cause error) {
-	cause = err
-
-	const maxDepth = 100
-	for i := 0; i <= maxDepth; i++ {
-		res := errors.Unwrap(cause)
-		if res == nil {
-			return cause
-		}
-		cause = res
-	}
-
-	logrus.Errorf("Max error depth of %d reached, cannot unwrap until root cause: %v", maxDepth, err)
-	return cause
-}

util/util_test.go

@@ -1,15 +1,12 @@
 package util
 
 import (
-	"errors"
-	"fmt"
 	"os"
 	"strconv"
 	"testing"
 
 	"github.com/containers/common/pkg/config"
 	specs "github.com/opencontainers/runtime-spec/specs-go"
-	"github.com/stretchr/testify/assert"
 )
 
 func TestMergeEnv(t *testing.T) {
@@ -138,47 +135,3 @@ func TestMountsSort(t *testing.T) {
 	}
 
 }
-
-func TestCause(t *testing.T) {
-	t.Parallel()
-
-	for _, tc := range []struct {
-		name        string
-		err         func() error
-		expectedErr error
-	}{
-		{
-			name:        "nil error",
-			err:         func() error { return nil },
-			expectedErr: nil,
-		},
-		{
-			name:        "equal errors",
-			err:         func() error { return errors.New("foo") },
-			expectedErr: errors.New("foo"),
-		},
-		{
-			name:        "wrapped error",
-			err:         func() error { return fmt.Errorf("baz: %w", fmt.Errorf("bar: %w", errors.New("foo"))) },
-			expectedErr: errors.New("foo"),
-		},
-		{
-			name: "max depth reached",
-			err: func() error {
-				err := errors.New("error")
-				for i := 0; i <= 101; i++ {
-					err = fmt.Errorf("%d: %w", i, err)
-				}
-				return err
-			},
-			expectedErr: fmt.Errorf("0: %w", errors.New("error")),
-		},
-	} {
-		tc := tc
-		t.Run(tc.name, func(t *testing.T) {
-			t.Parallel()
-			err := Cause(tc.err())
-			assert.Equal(t, tc.expectedErr, err)
-		})
-	}
-}