refactor: Simplify code with gopls modernize

alexandear · alexandear · commit 2fa2dc883062 · 2025-04-02T17:01:00.000+03:00
Signed-off-by: Oleksandr Redko &lt;oleksandr.red+github@gmail.com&gt;
diff --git a/.golangci.yml b/.golangci.yml
@@ -17,6 +17,7 @@ linters:
   - godot
   - govet
   - ineffassign
+  - intrange
   - misspell
   - nakedret
   - noctx
diff --git a/cmd/limactl/list.go b/cmd/limactl/list.go
@@ -22,10 +22,10 @@ func fieldNames() []string {
 	names := []string{}
 	var data store.FormatData
 	t := reflect.TypeOf(data)
-	for i := 0; i < t.NumField(); i++ {
+	for i := range t.NumField() {
 		f := t.Field(i)
 		if f.Anonymous {
-			for j := 0; j < f.Type.NumField(); j++ {
+			for j := range f.Type.NumField() {
 				names = append(names, f.Type.Field(j).Name)
 			}
 		} else {
diff --git a/cmd/limactl/prune.go b/cmd/limactl/prune.go
@@ -4,6 +4,7 @@
 package main
 
 import (
+	"maps"
 	"os"
 
 	"github.com/lima-vm/lima/pkg/downloader"
@@ -73,9 +74,7 @@ func knownLocations() (map[string]limayaml.File, error) {
 		if err != nil {
 			return nil, err
 		}
-		for k, v := range locationsFromLimaYAML(instance.Config) {
-			locations[k] = v
-		}
+		maps.Copy(locations, locationsFromLimaYAML(instance.Config))
 	}
 
 	// Collect locations from templates
@@ -92,9 +91,7 @@ func knownLocations() (map[string]limayaml.File, error) {
 		if err != nil {
 			return nil, err
 		}
-		for k, v := range locationsFromLimaYAML(y) {
-			locations[k] = v
-		}
+		maps.Copy(locations, locationsFromLimaYAML(y))
 	}
 	return locations, nil
 }
diff --git a/pkg/cidata/cidata.go b/pkg/cidata/cidata.go
@@ -8,6 +8,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"maps"
 	"net"
 	"net/url"
 	"os"
@@ -50,9 +51,7 @@ func setupEnv(instConfigEnv map[string]string, propagateProxyEnv bool, slirpGate
 		return env, err
 	}
 	// env.* settings from lima.yaml override system settings without giving a warning
-	for name, value := range instConfigEnv {
-		env[name] = value
-	}
+	maps.Copy(env, instConfigEnv)
 	// Current process environment setting override both system settings and env.*
 	lowerVars := []string{"ftp_proxy", "http_proxy", "https_proxy", "no_proxy"}
 	upperVars := make([]string, len(lowerVars))
diff --git a/pkg/downloader/downloader_test.go b/pkg/downloader/downloader_test.go
@@ -91,7 +91,7 @@ func TestDownloadRemote(t *testing.T) {
 		t.Run("parallel", func(t *testing.T) {
 			cacheDir := filepath.Join(t.TempDir(), "cache")
 			results := make(chan downloadResult, parallelDownloads)
-			for i := 0; i < parallelDownloads; i++ {
+			for range parallelDownloads {
 				go func() {
 					// Parallel download is supported only for different instances with unique localPath.
 					localPath := filepath.Join(t.TempDir(), t.Name())
@@ -131,7 +131,7 @@ func TestDownloadRemote(t *testing.T) {
 		t.Run("parallel", func(t *testing.T) {
 			cacheDir := filepath.Join(t.TempDir(), "cache")
 			results := make(chan downloadResult, parallelDownloads)
-			for i := 0; i < parallelDownloads; i++ {
+			for range parallelDownloads {
 				go func() {
 					r, err := Download(context.Background(), "", dummyRemoteFileURL,
 						WithExpectedDigest(dummyRemoteFileDigest), WithCacheDir(cacheDir))
@@ -177,7 +177,7 @@ func TestDownloadRemote(t *testing.T) {
 
 func countResults(t *testing.T, results chan downloadResult) (downloaded, cached int) {
 	t.Helper()
-	for i := 0; i < parallelDownloads; i++ {
+	for range parallelDownloads {
 		result := <-results
 		if result.err != nil {
 			t.Errorf("Download failed: %s", result.err)
diff --git a/pkg/guestagent/procnettcp/procnettcp.go b/pkg/guestagent/procnettcp/procnettcp.go
@@ -65,7 +65,7 @@ func ParseWithEndian(r io.Reader, kind Kind, isBE bool) ([]Entry, error) {
 		fields := strings.Fields(line)
 		switch i {
 		case 0:
-			for j := 0; j < len(fields); j++ {
+			for j := range fields {
 				fieldNames[fields[j]] = j
 			}
 			if _, ok := fieldNames["local_address"]; !ok {
@@ -135,18 +135,18 @@ func ParseAddressWithEndian(s string, isBE bool) (net.IP, uint16, error) {
 	}
 
 	ipBytes := make([]byte, len(split[0])/2) // 4 bytes (8 chars) or 16 bytes (32 chars)
-	for i := 0; i < len(split[0])/8; i++ {
+	for i := range len(split[0]) / 8 {
 		quartet := split[0][8*i : 8*(i+1)]
 		quartetB, err := hex.DecodeString(quartet) // surprisingly little endian, per 4 bytes, on little endian hosts
 		if err != nil {
 			return nil, 0, fmt.Errorf("unparsable address %q: unparsable quartet %q: %w", s, quartet, err)
 		}
 		if isBE {
-			for j := 0; j < len(quartetB); j++ {
+			for j := range quartetB {
 				ipBytes[4*i+j] = quartetB[j]
 			}
 		} else {
-			for j := 0; j < len(quartetB); j++ {
+			for j := range quartetB {
 				ipBytes[4*i+len(quartetB)-1-j] = quartetB[j]
 			}
 		}
diff --git a/pkg/hostagent/requirements.go b/pkg/hostagent/requirements.go
@@ -23,7 +23,7 @@ func (a *HostAgent) waitForRequirements(label string, requirements []requirement
 
 	for i, req := range requirements {
 	retryLoop:
-		for j := 0; j < retries; j++ {
+		for j := range retries {
 			logrus.Infof("Waiting for the %s requirement %d of %d: %q", label, i+1, len(requirements), req.description)
 			err := a.waitForRequirement(req)
 			if err == nil {
diff --git a/pkg/limatmpl/embed_test.go b/pkg/limatmpl/embed_test.go
@@ -437,7 +437,7 @@ func RunEmbedTest(t *testing.T, tc embedTestCase) {
 		assert.NilError(t, err, tc.description)
 	}
 	tmpl := &limatmpl.Template{
-		Bytes:   []byte(fmt.Sprintf("base: base0.yaml\n%s", tc.template)),
+		Bytes:   fmt.Appendf(nil, "base: base0.yaml\n%s", tc.template),
 		Locator: "tmpl.yaml",
 	}
 	// Don't include `base` property if base0 is a script
diff --git a/pkg/limatmpl/locator.go b/pkg/limatmpl/locator.go
@@ -191,7 +191,7 @@ images:
 - location: %q
   arch: %q
 `
-	tmpl.Bytes = []byte(fmt.Sprintf(template, imageArch, locator, imageArch))
+	tmpl.Bytes = fmt.Appendf(nil, template, imageArch, locator, imageArch)
 	tmpl.Name = InstNameFromImageURL(locator, imageArch)
 	return true
 }
diff --git a/pkg/limayaml/defaults.go b/pkg/limayaml/defaults.go
@@ -9,6 +9,7 @@ import (
 	_ "embed"
 	"errors"
 	"fmt"
+	"maps"
 	"net"
 	"os"
 	"os/user"
@@ -470,15 +471,9 @@ func FillDefault(y, d, o *LimaYAML, filePath string, warn bool) {
 
 	hosts := make(map[string]string)
 	// Values can be either names or IP addresses. Name values are canonicalized in the hostResolver.
-	for k, v := range d.HostResolver.Hosts {
-		hosts[k] = v
-	}
-	for k, v := range y.HostResolver.Hosts {
-		hosts[k] = v
-	}
-	for k, v := range o.HostResolver.Hosts {
-		hosts[k] = v
-	}
+	maps.Copy(hosts, d.HostResolver.Hosts)
+	maps.Copy(hosts, y.HostResolver.Hosts)
+	maps.Copy(hosts, o.HostResolver.Hosts)
 	y.HostResolver.Hosts = hosts
 
 	y.Provision = slices.Concat(o.Provision, y.Provision, d.Provision)
@@ -852,27 +847,15 @@ func FillDefault(y, d, o *LimaYAML, filePath string, warn bool) {
 	}
 
 	env := make(map[string]string)
-	for k, v := range d.Env {
-		env[k] = v
-	}
-	for k, v := range y.Env {
-		env[k] = v
-	}
-	for k, v := range o.Env {
-		env[k] = v
-	}
+	maps.Copy(env, d.Env)
+	maps.Copy(env, y.Env)
+	maps.Copy(env, o.Env)
 	y.Env = env
 
 	param := make(map[string]string)
-	for k, v := range d.Param {
-		param[k] = v
-	}
-	for k, v := range y.Param {
-		param[k] = v
-	}
-	for k, v := range o.Param {
-		param[k] = v
-	}
+	maps.Copy(param, d.Param)
+	maps.Copy(param, y.Param)
+	maps.Copy(param, o.Param)
 	y.Param = param
 
 	if y.CACertificates.RemoveDefaults == nil {
diff --git a/pkg/limayaml/validate.go b/pkg/limayaml/validate.go
@@ -12,6 +12,7 @@ import (
 	"path/filepath"
 	"regexp"
 	"runtime"
+	"slices"
 	"strconv"
 	"strings"
 	"unicode"
@@ -198,10 +199,8 @@ func Validate(y *LimaYAML, warn bool) error {
 		return fmt.Errorf("field `mountType` must be %q or %q or %q, or %q, got %q", REVSSHFS, NINEP, VIRTIOFS, WSLMount, *y.MountType)
 	}
 
-	for _, f := range y.MountTypesUnsupported {
-		if f == *y.MountType {
-			return fmt.Errorf("field `mountType` must not be one of %v (`mountTypesUnsupported`), got %q", y.MountTypesUnsupported, *y.MountType)
-		}
+	if slices.Contains(y.MountTypesUnsupported, *y.MountType) {
+		return fmt.Errorf("field `mountType` must not be one of %v (`mountTypesUnsupported`), got %q", y.MountTypesUnsupported, *y.MountType)
 	}
 
 	if warn && runtime.GOOS != "linux" {
@@ -341,7 +340,7 @@ func Validate(y *LimaYAML, warn bool) error {
 				return err
 			}
 		}
-		for j := 0; j < 2; j++ {
+		for j := range 2 {
 			if err := validatePort(fmt.Sprintf("%s.guestPortRange[%d]", field, j), rule.GuestPortRange[j]); err != nil {
 				return err
 			}
diff --git a/pkg/lockutil/lockutil_test.go b/pkg/lockutil/lockutil_test.go
@@ -21,7 +21,7 @@ func TestWithDirLock(t *testing.T) {
 	log := filepath.Join(dir, "log")
 
 	errc := make(chan error, 10)
-	for i := 0; i < parallel; i++ {
+	for i := range parallel {
 		go func() {
 			err := WithDirLock(dir, func() error {
 				if _, err := os.Stat(log); err == nil {
@@ -43,7 +43,7 @@ func TestWithDirLock(t *testing.T) {
 		}()
 	}
 
-	for i := 0; i < parallel; i++ {
+	for range parallel {
 		err := <-errc
 		if err != nil {
 			t.Error(err)
diff --git a/pkg/networks/validate.go b/pkg/networks/validate.go
@@ -21,7 +21,7 @@ func (c *Config) Validate() error {
 	paths := reflect.ValueOf(&c.Paths).Elem()
 	pathsMap := make(map[string]string, paths.NumField())
 	var socketVMNetNotFound bool
-	for i := 0; i < paths.NumField(); i++ {
+	for i := range paths.NumField() {
 		// extract YAML name from struct tag; strip options like "omitempty"
 		name := paths.Type().Field(i).Tag.Get("yaml")
 		if i := strings.IndexRune(name, ','); i > -1 {
diff --git a/pkg/qemu/qemu_driver.go b/pkg/qemu/qemu_driver.go
@@ -149,7 +149,7 @@ func (l *LimaQemuDriver) Start(ctx context.Context) (chan error, error) {
 
 		vhostSock := filepath.Join(l.Instance.Dir, fmt.Sprintf(filenames.VhostSock, i))
 		vhostSockExists := false
-		for attempt := 0; attempt < 5; attempt++ {
+		for attempt := range 5 {
 			logrus.Debugf("Try waiting for %s to appear (attempt %d)", vhostSock, attempt)
 
 			if _, err := os.Stat(vhostSock); err != nil {
diff --git a/pkg/reflectutil/reflectutil.go b/pkg/reflectutil/reflectutil.go
@@ -38,7 +38,7 @@ func UnknownNonEmptyFields(structOrStructPtr any, knownNames ...string) []string
 	default:
 		panic(fmt.Errorf("expected Ptr or Struct, got %+v", kind))
 	}
-	for i := 0; i < val.NumField(); i++ {
+	for i := range val.NumField() {
 		iField := val.Field(i)
 		if isEmpty(iField) {
 			continue
diff --git a/pkg/vz/network_darwin_test.go b/pkg/vz/network_darwin_test.go
@@ -49,14 +49,14 @@ func TestDialQemu(t *testing.T) {
 	go func() {
 		t.Log("Sender started")
 		buf := make([]byte, vmnetMaxPacketSize)
-		for i := 0; i < vmnetMaxPacketSize; i++ {
+		for i := range vmnetMaxPacketSize {
 			buf[i] = 0x55
 		}
 
 		// data packet format:
 		//     0-4		packet number
 		//     4-1514	0x55 ...
-		for i := 0; i < packetsCount; i++ {
+		for i := range packetsCount {
 			binary.BigEndian.PutUint32(buf, uint32(i))
 			if _, err := vzConn.Write(buf); err != nil {
 				errc <- err
@@ -82,7 +82,7 @@ func TestDialQemu(t *testing.T) {
 	buf := make([]byte, vmnetMaxPacketSize)
 
 	t.Logf("Receiving and verifying data packets...")
-	for i := 0; i < packetsCount; i++ {
+	for i := range packetsCount {
 		n, err := vzConn.Read(buf)
 		assert.NilError(t, err)
 		assert.Assert(t, n >= vmnetMaxPacketSize, "unexpected number of bytes")
@@ -96,7 +96,7 @@ func TestDialQemu(t *testing.T) {
 	}
 	t.Logf("Received and verified %d data packets", packetsCount)
 
-	for i := 0; i < 2; i++ {
+	for range 2 {
 		err := <-errc
 		assert.NilError(t, err)
 	}

Original file line number	Diff line number	Diff line change
`@@ -4,6 +4,7 @@`
`4`	`4`	`package main`
`5`	`5`
`6`	`6`	`import (`
	`7`	`+ "maps"`
`7`	`8`	`"os"`
`8`	`9`
`9`	`10`	`"github.com/lima-vm/lima/pkg/downloader"`
`@@ -73,9 +74,7 @@ func knownLocations() (map[string]limayaml.File, error) {`
`73`	`74`	`if err != nil {`
`74`	`75`	`return nil, err`
`75`	`76`	`}`
`76`		`- for k, v := range locationsFromLimaYAML(instance.Config) {`
`77`		`- locations[k] = v`
`78`		`- }`
	`77`	`+ maps.Copy(locations, locationsFromLimaYAML(instance.Config))`
`79`	`78`	`}`
`80`	`79`
`81`	`80`	`// Collect locations from templates`
`@@ -92,9 +91,7 @@ func knownLocations() (map[string]limayaml.File, error) {`
`92`	`91`	`if err != nil {`
`93`	`92`	`return nil, err`
`94`	`93`	`}`
`95`		`- for k, v := range locationsFromLimaYAML(y) {`
`96`		`- locations[k] = v`
`97`		`- }`
	`94`	`+ maps.Copy(locations, locationsFromLimaYAML(y))`
`98`	`95`	`}`
`99`	`96`	`return locations, nil`
`100`	`97`	`}`
Original file line number	Diff line number	Diff line change
`@@ -65,7 +65,7 @@ func ParseWithEndian(r io.Reader, kind Kind, isBE bool) ([]Entry, error) {`
`65`	`65`	`fields := strings.Fields(line)`
`66`	`66`	`switch i {`
`67`	`67`	`case 0:`
`68`		`- for j := 0; j < len(fields); j++ {`
	`68`	`+ for j := range fields {`
`69`	`69`	`fieldNames[fields[j]] = j`
`70`	`70`	`}`
`71`	`71`	`if _, ok := fieldNames["local_address"]; !ok {`
`@@ -135,18 +135,18 @@ func ParseAddressWithEndian(s string, isBE bool) (net.IP, uint16, error) {`
`135`	`135`	`}`
`136`	`136`
`137`	`137`	`ipBytes := make([]byte, len(split[0])/2) // 4 bytes (8 chars) or 16 bytes (32 chars)`
`138`		`- for i := 0; i < len(split[0])/8; i++ {`
	`138`	`+ for i := range len(split[0]) / 8 {`
`139`	`139`	`quartet := split[0][8i : 8(i+1)]`
`140`	`140`	`quartetB, err := hex.DecodeString(quartet) // surprisingly little endian, per 4 bytes, on little endian hosts`
`141`	`141`	`if err != nil {`
`142`	`142`	`return nil, 0, fmt.Errorf("unparsable address %q: unparsable quartet %q: %w", s, quartet, err)`
`143`	`143`	`}`
`144`	`144`	`if isBE {`
`145`		`- for j := 0; j < len(quartetB); j++ {`
	`145`	`+ for j := range quartetB {`
`146`	`146`	`ipBytes[4*i+j] = quartetB[j]`
`147`	`147`	`}`
`148`	`148`	`} else {`
`149`		`- for j := 0; j < len(quartetB); j++ {`
	`149`	`+ for j := range quartetB {`
`150`	`150`	`ipBytes[4*i+len(quartetB)-1-j] = quartetB[j]`
`151`	`151`	`}`
`152`	`152`	`}`
Original file line number	Diff line number	Diff line change
`@@ -437,7 +437,7 @@ func RunEmbedTest(t *testing.T, tc embedTestCase) {`
`437`	`437`	`assert.NilError(t, err, tc.description)`
`438`	`438`	`}`
`439`	`439`	`tmpl := &limatmpl.Template{`
`440`		`- Bytes: []byte(fmt.Sprintf("base: base0.yaml\n%s", tc.template)),`
	`440`	`+ Bytes: fmt.Appendf(nil, "base: base0.yaml\n%s", tc.template),`
`441`	`441`	`Locator: "tmpl.yaml",`
`442`	`442`	`}`
`443`	`443`	// Don't include `base` property if base0 is a script
Original file line number	Diff line number	Diff line change
`@@ -191,7 +191,7 @@ images:`
`191`	`191`	`- location: %q`
`192`	`192`	`arch: %q`
`193`	`193`	`
`194`		`- tmpl.Bytes = []byte(fmt.Sprintf(template, imageArch, locator, imageArch))`
	`194`	`+ tmpl.Bytes = fmt.Appendf(nil, template, imageArch, locator, imageArch)`
`195`	`195`	`tmpl.Name = InstNameFromImageURL(locator, imageArch)`
`196`	`196`	`return true`
`197`	`197`	`}`