enable nonamedreturns linter

Signed-off-by: Matthieu MOREL <matthieu.morel35@gmail.com>

.golangci.yml

@@ -5,6 +5,7 @@ linters:
     - gofumpt
     - ineffassign
     - misspell
+    - nonamedreturns
     - staticcheck
   disable:
     - errcheck

pkg/ip/link_linux.go

@@ -67,38 +67,37 @@ func peerExists(name string) bool {
 	return true
 }
 
-func makeVeth(name, vethPeerName string, mtu int, mac string, hostNS ns.NetNS) (peerName string, veth netlink.Link, err error) {
+func makeVeth(name, vethPeerName string, mtu int, mac string, hostNS ns.NetNS) (string, netlink.Link, error) {
+	var peerName string
+	var veth netlink.Link
+	var err error
 	for i := 0; i < 10; i++ {
 		if vethPeerName != "" {
 			peerName = vethPeerName
 		} else {
 			peerName, err = RandomVethName()
 			if err != nil {
-				return
+				return peerName, nil, err
 			}
 		}
 
 		veth, err = makeVethPair(name, peerName, mtu, mac, hostNS)
 		switch {
 		case err == nil:
-			return
+			return peerName, veth, err
 
 		case os.IsExist(err):
 			if peerExists(peerName) && vethPeerName == "" {
 				continue
 			}
-			err = fmt.Errorf("container veth name provided (%v) already exists", name)
-			return
-
+			return peerName, veth, fmt.Errorf("container veth name provided (%v) already exists", name)
 		default:
-			err = fmt.Errorf("failed to make veth pair: %v", err)
-			return
+			return peerName, veth, fmt.Errorf("failed to make veth pair: %v", err)
 		}
 	}
 
 	// should really never be hit
-	err = fmt.Errorf("failed to find a unique veth name")
-	return
+	return peerName, nil, fmt.Errorf("failed to find a unique veth name")
 }
 
 // RandomVethName returns string "veth" with random prefix (hashed from entropy)

plugins/ipam/dhcp/lease.go

@@ -84,8 +84,11 @@ var requestOptionsDefault = map[dhcp4.OptionCode]bool{
 }
 
 func prepareOptions(cniArgs string, ProvideOptions []ProvideOption, RequestOptions []RequestOption) (
-	optsRequesting map[dhcp4.OptionCode]bool, optsProviding map[dhcp4.OptionCode][]byte, err error,
+	map[dhcp4.OptionCode]bool, map[dhcp4.OptionCode][]byte, error,
 ) {
+	var optsRequesting map[dhcp4.OptionCode]bool
+	var optsProviding map[dhcp4.OptionCode][]byte
+	var err error
 	// parse CNI args
 	cniArgsParsed := map[string]string{}
 	for _, argPair := range strings.Split(cniArgs, ";") {
@@ -101,20 +104,17 @@ func prepareOptions(cniArgs string, ProvideOptions []ProvideOption, RequestOptio
 	for _, opt := range ProvideOptions {
 		optParsed, err = parseOptionName(string(opt.Option))
 		if err != nil {
-			err = fmt.Errorf("Can not parse option %q: %w", opt.Option, err)
-			return
+			return nil, nil, fmt.Errorf("Can not parse option %q: %w", opt.Option, err)
 		}
 		if len(opt.Value) > 0 {
 			if len(opt.Value) > 255 {
-				err = fmt.Errorf("value too long for option %q: %q", opt.Option, opt.Value)
-				return
+				return nil, nil, fmt.Errorf("value too long for option %q: %q", opt.Option, opt.Value)
 			}
 			optsProviding[optParsed] = []byte(opt.Value)
 		}
 		if value, ok := cniArgsParsed[opt.ValueFromCNIArg]; ok {
 			if len(value) > 255 {
-				err = fmt.Errorf("value too long for option %q from CNI_ARGS %q: %q", opt.Option, opt.ValueFromCNIArg, opt.Value)
-				return
+				return nil, nil, fmt.Errorf("value too long for option %q from CNI_ARGS %q: %q", opt.Option, opt.ValueFromCNIArg, opt.Value)
 			}
 			optsProviding[optParsed] = []byte(value)
 		}
@@ -129,8 +129,7 @@ func prepareOptions(cniArgs string, ProvideOptions []ProvideOption, RequestOptio
 		}
 		optParsed, err = parseOptionName(string(opt.Option))
 		if err != nil {
-			err = fmt.Errorf("Can not parse option %q: %w", opt.Option, err)
-			return
+			return nil, nil, fmt.Errorf("Can not parse option %q: %w", opt.Option, err)
 		}
 		optsRequesting[optParsed] = true
 	}
@@ -140,7 +139,7 @@ func prepareOptions(cniArgs string, ProvideOptions []ProvideOption, RequestOptio
 			optsRequesting[k] = v
 		}
 	}
-	return
+	return optsRequesting, optsProviding, err
 }
 
 // AcquireLease gets an DHCP lease and then maintains it in the background