chore(gonf): fix errcheck and shadow errors

15 files changed, 64 insertions, 79 deletions

diff --git a/cmd/gonf/cmd_build.go b/cmd/gonf/cmd_build.go
index ebcde29..6a59b4b 100644
--- a/cmd/gonf/cmd_build.go
+++ b/cmd/gonf/cmd_build.go
@@ -19,7 +19,7 @@ func cmdBuild(ctx context.Context,
 where FLAG can be one or more of`, flag.ContinueOnError)
 	hostFlag := addHostFlag(f)
 	f.SetOutput(stderr)
-	f.Parse(args)
+	_ = f.Parse(args)
 	if helpMode {
 		f.SetOutput(stdout)
 		f.Usage()
@@ -32,17 +32,23 @@ where FLAG can be one or more of`, flag.ContinueOnError)
 	return runBuild(ctx, stderr, hostDir)
 }
 
-func runBuild(ctx context.Context, stderr io.Writer, hostDir string) error {
+func runBuild(ctx context.Context, stderr io.Writer, hostDir string) (err error) {
 	wd, err := os.Getwd()
 	if err != nil {
 		return err
 	}
-	defer os.Chdir(wd)
-	os.Chdir(hostDir)
+	defer func() {
+		if e := os.Chdir(wd); err == nil {
+			err = e
+		}
+	}()
+	if err = os.Chdir(hostDir); err != nil {
+		return err
+	}
 	cmd := exec.CommandContext(ctx, "go", "build", "-ldflags", "-s -w -extldflags \"-static\"", hostDir)
 	cmd.Env = append(cmd.Environ(), "CGO_ENABLED=0")
 	if out, err := cmd.CombinedOutput(); err != nil {
-		fmt.Fprint(stderr, string(out))
+		_, _ = fmt.Fprint(stderr, string(out))
 		return err
 	}
 	return nil
diff --git a/cmd/gonf/main.go b/cmd/gonf/main.go
index 8dae51d..fe6f065 100644
--- a/cmd/gonf/main.go
+++ b/cmd/gonf/main.go
@@ -49,11 +49,13 @@ where FLAG can be one or more of`, flag.ContinueOnError)
 	f.BoolVar(&helpMode, "help", false, "show contextual help")
 	f.StringVar(&configDir, "config", "", "(REQUIRED for most commands) path to a gonf configurations repository (overrides the GONF_CONFIG environment variable)")
 	f.SetOutput(stderr)
-	f.Parse(args[1:])
+	if err := f.Parse(args[1:]); err != nil {
+		return err
+	}
 
 	if f.NArg() < 1 {
 		f.Usage()
-		return errors.New("No command given")
+		return errors.New("no command given")
 	}
 	cmd := f.Arg(0)
 	argsTail := f.Args()[1:]
@@ -68,7 +70,7 @@ where FLAG can be one or more of`, flag.ContinueOnError)
 			configDir = getenv("GONF_CONFIG")
 			if configDir == "" {
 				f.Usage()
-				return errors.New("The GONF_CONFIG environment variable is unset and the -config FLAG is missing. Please use one or the other.")
+				return errors.New("the GONF_CONFIG environment variable is unset and the -config FLAG is missing. Please use one or the other")
 			}
 		}
 		switch cmd {
@@ -76,7 +78,7 @@ where FLAG can be one or more of`, flag.ContinueOnError)
 			return cmdBuild(ctx, f, argsTail, getenv, stdout, stderr)
 		default:
 			f.Usage()
-			return fmt.Errorf("Invalid command: %s", cmd)
+			return fmt.Errorf("invalid command: %s", cmd)
 		}
 	}
 	return nil
diff --git a/pkg/commands.go b/pkg/commands.go
index 5403e5f..096da11 100644
--- a/pkg/commands.go
+++ b/pkg/commands.go
@@ -6,15 +6,12 @@ import (
 	"os/exec"
 )
 
-// ----- Globals ---------------------------------------------------------------
 var commands []*CommandPromise
 
-// ----- Init ------------------------------------------------------------------
 func init() {
 	commands = make([]*CommandPromise, 0)
 }
 
-// ----- Public ----------------------------------------------------------------
 func Command(cmd string, args ...string) *CommandPromise {
 	return CommandWithEnv([]string{}, cmd, args...)
 }
@@ -81,7 +78,6 @@ func (c CommandPromise) Status() Status {
 	return c.status
 }
 
-// ----- Internal --------------------------------------------------------------
 func resolveCommands() (status Status) {
 	status = KEPT
 	for _, c := range commands {
diff --git a/pkg/files.go b/pkg/files.go
index eb3fa38..2fe0f6e 100644
--- a/pkg/files.go
+++ b/pkg/files.go
@@ -11,15 +11,12 @@ import (
 	"path/filepath"
 )
 
-// ----- Globals ---------------------------------------------------------------
 var files []*FilePromise
 
-// ----- Init ------------------------------------------------------------------
 func init() {
 	files = make([]*FilePromise, 0)
 }
 
-// ----- Public ----------------------------------------------------------------
 type FilePromise struct {
 	chain          []Promise
 	contents       Value
@@ -62,7 +59,6 @@ func (f *FilePromise) Template(contents any) *FilePromise {
 	return f
 }
 
-// We want to satisfy the Promise interface
 func (f *FilePromise) IfRepaired(p ...Promise) Promise {
 	f.chain = append(f.chain, p...)
 	return f
@@ -127,7 +123,6 @@ func (f FilePromise) Status() Status {
 	return f.status
 }
 
-// ----- Internal --------------------------------------------------------------
 func resolveFiles() (status Status) {
 	status = KEPT
 	for _, f := range files {
@@ -144,12 +139,16 @@ func resolveFiles() (status Status) {
 	return
 }
 
-func sha256sumOfFile(filename string) ([]byte, error) {
+func sha256sumOfFile(filename string) (hash []byte, err error) {
 	f, err := os.Open(filename)
 	if err != nil {
 		return nil, err
 	}
-	defer f.Close()
+	defer func() {
+		if e := f.Close(); err == nil {
+			err = e
+		}
+	}()
 	h := sha256.New()
 	if _, err := io.Copy(h, f); err != nil {
 		return nil, err
@@ -157,12 +156,16 @@ func sha256sumOfFile(filename string) ([]byte, error) {
 	return h.Sum(nil), nil
 }
 
-func writeFile(filename string, contents []byte) error {
+func writeFile(filename string, contents []byte) (err error) {
 	f, err := os.Create(filename)
 	if err != nil {
 		return err
 	}
-	defer f.Close()
+	defer func() {
+		if e := f.Close(); err == nil {
+			err = e
+		}
+	}()
 	_, err = f.Write(contents)
 	return err
 }
diff --git a/pkg/packages.go b/pkg/packages.go
index bf9322c..87db647 100644
--- a/pkg/packages.go
+++ b/pkg/packages.go
@@ -2,20 +2,16 @@ package gonf
 
 import "log/slog"
 
-// ----- Globals ---------------------------------------------------------------
 var packages []*PackagePromise
 
-// packages management functions
-var packages_install_function func([]string) (Status, []string)
+var packagesInstallFunction func([]string) (Status, []string)
 
-// ----- Init ------------------------------------------------------------------
 func init() {
 	packages = make([]*PackagePromise, 0)
 }
 
-// ----- Public ----------------------------------------------------------------
 func SetPackagesConfiguration(install func([]string) (Status, []string), update *CommandPromise) {
-	packages_install_function = install
+	packagesInstallFunction = install
 }
 
 func Package(names ...string) *PackagePromise {
@@ -45,7 +41,7 @@ func (p *PackagePromise) Promise() Promise {
 }
 
 func (p *PackagePromise) Resolve() {
-	status, affected := packages_install_function(p.names)
+	status, affected := packagesInstallFunction(p.names)
 	switch status {
 	case BROKEN:
 		slog.Error("package", "names", p.names, "status", status, "broke", affected)
@@ -63,7 +59,6 @@ func (p PackagePromise) Status() Status {
 	return p.status
 }
 
-// ----- Internal --------------------------------------------------------------
 func resolvePackages() (status Status) {
 	status = KEPT
 	for _, c := range packages {
diff --git a/pkg/permissions.go b/pkg/permissions.go
index 91287c0..9a46b64 100644
--- a/pkg/permissions.go
+++ b/pkg/permissions.go
@@ -29,10 +29,10 @@ func (p *Permissions) resolve(filename string) (Status, error) {
 		if group, err := user.LookupGroup(p.group.String()); err != nil {
 			return BROKEN, err
 		} else {
-			if groupId, err := strconv.Atoi(group.Gid); err != nil {
+			if groupID, err := strconv.Atoi(group.Gid); err != nil {
 				return BROKEN, err
 			} else {
-				g = &IntValue{groupId}
+				g = &IntValue{groupID}
 				p.group = g
 			}
 		}
@@ -46,10 +46,10 @@ func (p *Permissions) resolve(filename string) (Status, error) {
 		if user, err := user.Lookup(p.user.String()); err != nil {
 			return BROKEN, err
 		} else {
-			if userId, err := strconv.Atoi(user.Uid); err != nil {
+			if userID, err := strconv.Atoi(user.Uid); err != nil {
 				return BROKEN, err
 			} else {
-				u = &IntValue{userId}
+				u = &IntValue{userID}
 				p.group = u
 			}
 		}
diff --git a/pkg/services.go b/pkg/services.go
index 7e4f114..319599e 100644
--- a/pkg/services.go
+++ b/pkg/services.go
@@ -2,18 +2,14 @@ package gonf
 
 import "log/slog"
 
-// ----- Globals ---------------------------------------------------------------
 var services []*ServicePromise
 
-// service management function
 var serviceFunction func(string, string) (Status, error)
 
-// ----- Init ------------------------------------------------------------------
 func init() {
 	services = make([]*ServicePromise, 0)
 }
 
-// ----- Public ----------------------------------------------------------------
 func SetServiceFunction(f func(string, string) (Status, error)) {
 	serviceFunction = f
 }
@@ -82,7 +78,6 @@ func (s ServicePromise) Status() Status {
 	return s.status
 }
 
-// ----- Internal --------------------------------------------------------------
 func resolveServices() (status Status) {
 	status = KEPT
 	for _, c := range services {
diff --git a/pkg/templates.go b/pkg/templates.go
index 736bbe0..1339306 100644
--- a/pkg/templates.go
+++ b/pkg/templates.go
@@ -7,17 +7,14 @@ import (
 	"text/template"
 )
 
-// ----- Globals ---------------------------------------------------------------
 var templates *template.Template
 
-// ----- Init ------------------------------------------------------------------
 func init() {
 	templates = template.New("")
 	templates.Option("missingkey=error")
 	templates.Funcs(builtinTemplateFunctions)
 }
 
-// ----- Public ----------------------------------------------------------------
 type TemplateValue struct {
 	contents []byte
 	data     string
diff --git a/pkg/users.go b/pkg/users.go
index ca7913b..2577207 100644
--- a/pkg/users.go
+++ b/pkg/users.go
@@ -4,20 +4,16 @@ import (
 	"log/slog"
 )
 
-// ----- Globals ---------------------------------------------------------------
 var users []*UserPromise
 
-// users management functions
-var user_add_function func(data UserData) (Status, error)
+var userAddFunction func(data UserData) (Status, error)
 
-// ----- Init ------------------------------------------------------------------
 func init() {
 	users = make([]*UserPromise, 0)
 }
 
-// ----- Public ----------------------------------------------------------------
 func SetUsersConfiguration(useradd func(data UserData) (Status, error)) {
-	user_add_function = useradd
+	userAddFunction = useradd
 }
 
 func User(data UserData) *UserPromise {
@@ -57,7 +53,7 @@ func (u *UserPromise) Promise() Promise {
 
 func (u *UserPromise) Resolve() {
 	var err error
-	u.status, err = user_add_function(u.data)
+	u.status, err = userAddFunction(u.data)
 	switch u.status {
 	case BROKEN:
 		slog.Error("user", "name", u.data.Name, "status", u.status, "error", err)
@@ -77,7 +73,6 @@ func (u UserPromise) Status() Status {
 	return u.status
 }
 
-// ----- Internal --------------------------------------------------------------
 func resolveUsers() (status Status) {
 	status = KEPT
 	for _, c := range users {
diff --git a/pkg/utils.go b/pkg/utils.go
index c3301f2..3920737 100644
--- a/pkg/utils.go
+++ b/pkg/utils.go
@@ -28,15 +28,19 @@ func FilterSlice[T any](slice *[]T, predicate func(T) bool) {
 func makeDirectoriesHierarchy(dir string, perms *Permissions) (Status, error) {
 	if _, err := os.Lstat(dir); err != nil {
 		if errors.Is(err, fs.ErrNotExist) {
-			if status, err := makeDirectoriesHierarchy(filepath.Dir(dir), perms); err != nil {
-				return status, err
+			if _, err = makeDirectoriesHierarchy(filepath.Dir(dir), perms); err != nil {
+				return BROKEN, err
+			}
+			var m int
+			if m, err = perms.mode.Int(); err != nil {
+				return BROKEN, err
+			}
+			if err = os.Mkdir(dir, fs.FileMode(m)); err != nil {
+				return BROKEN, err
 			}
-			m, err := perms.mode.Int()
-			if err != nil {
+			if _, err = perms.resolve(dir); err != nil {
 				return BROKEN, err
 			}
-			os.Mkdir(dir, fs.FileMode(m))
-			perms.resolve(dir)
 			return REPAIRED, nil
 		} else {
 			return BROKEN, err
diff --git a/pkg/values.go b/pkg/values.go
index 25f31e4..70fc9fe 100644
--- a/pkg/values.go
+++ b/pkg/values.go
@@ -47,7 +47,6 @@ func interfaceToTemplateValue(v any) Value {
 	panic(fmt.Sprintf("interfaceToTemplateValue cannot take type %T as argument. Value was %#v.", v, v))
 }
 
-// ----- BytesValue ------------------------------------------------------------
 type BytesValue struct {
 	value []byte
 }
@@ -62,7 +61,6 @@ func (b BytesValue) String() string {
 	return string(b.value[:])
 }
 
-// ----- IntValue --------------------------------------------------------------
 type IntValue struct {
 	value int
 }
@@ -77,7 +75,6 @@ func (i IntValue) String() string {
 	return fmt.Sprint(i.value)
 }
 
-// ----- StringsListValue ------------------------------------------------------
 type StringsListValue struct {
 	value []string
 }
@@ -95,7 +92,6 @@ func (s StringsListValue) String() string {
 	return strings.Join(s.value, "\n")
 }
 
-// ----- StringValue -----------------------------------------------------------
 type StringValue struct {
 	value string
 }
diff --git a/pkg/variables.go b/pkg/variables.go
index bb3096d..4c9bb56 100644
--- a/pkg/variables.go
+++ b/pkg/variables.go
@@ -5,15 +5,12 @@ import (
 	"log/slog"
 )
 
-// ----- Globals ---------------------------------------------------------------
 var variables map[string]*VariablePromise
 
-// ----- Init ------------------------------------------------------------------
 func init() {
 	variables = make(map[string]*VariablePromise)
 }
 
-// ----- Public ----------------------------------------------------------------
 func AppendVariable(name string, values ...string) *VariablePromise {
 	if v, ok := variables[name]; ok {
 		if l, ok := v.value.(*StringsListValue); ok {
@@ -66,7 +63,6 @@ type VariablePromise struct {
 	value     Value
 }
 
-// We want VariablePromise to satisfy the Value interface
 func (s VariablePromise) Bytes() []byte {
 	return s.value.Bytes()
 }
@@ -77,7 +73,6 @@ func (s VariablePromise) String() string {
 	return s.value.String()
 }
 
-// ----- Internal --------------------------------------------------------------
 func getVariable(name string) string {
 	if v, ok := variables[name]; ok {
 		return v.value.String()
diff --git a/stdlib/os/debian/apt.go b/stdlib/os/debian/apt.go
index 3386f20..3b72b9f 100644
--- a/stdlib/os/debian/apt.go
+++ b/stdlib/os/debian/apt.go
@@ -14,10 +14,10 @@ import (
 var packages map[string]string
 
 func init() {
-	packages_list()
+	packagesList()
 }
 
-func packages_install(names []string) (gonf.Status, []string) {
+func packagesInstall(names []string) (gonf.Status, []string) {
 	gonf.FilterSlice(&names, func(n string) bool {
 		_, ok := packages[n]
 		return !ok
@@ -28,11 +28,11 @@ func packages_install(names []string) (gonf.Status, []string) {
 	args := append([]string{"install", "-y", "--no-install-recommends"}, names...)
 	cmd := gonf.CommandWithEnv([]string{"DEBIAN_FRONTEND=noninteractive", "LC_ALL=C"}, "apt-get", args...)
 	cmd.Resolve()
-	packages_list()
+	packagesList()
 	return cmd.Status(), names
 }
 
-func packages_list() {
+func packagesList() {
 	packages = make(map[string]string)
 	ecmd := exec.Command("dpkg-query", "-W")
 	out, err := ecmd.CombinedOutput()
diff --git a/stdlib/os/debian/debian.go b/stdlib/os/debian/debian.go
index 9954088..95af85d 100644
--- a/stdlib/os/debian/debian.go
+++ b/stdlib/os/debian/debian.go
@@ -2,21 +2,22 @@ package debian
 
 import (
 	_ "embed"
-	"git.adyxax.org/adyxax/gonf/v2/pkg"
+
+	gonf "git.adyxax.org/adyxax/gonf/v2/pkg"
 	"git.adyxax.org/adyxax/gonf/v2/stdlib/os/linux"
 	"git.adyxax.org/adyxax/gonf/v2/stdlib/os/systemd"
 )
 
 //go:embed apt-norecommends
-var apt_norecommends []byte
+var aptNoRecommends []byte
 
 //go:embed sources.list
-var sources_list []byte
+var sourcesList []byte
 
 func Promise() {
 	// ----- gonf --------------------------------------------------------------
-	apt_update := gonf.Command("apt-get", "update", "-qq")
-	gonf.SetPackagesConfiguration(packages_install, apt_update)
+	aptUpdate := gonf.Command("apt-get", "update", "-qq")
+	gonf.SetPackagesConfiguration(packagesInstall, aptUpdate)
 	gonf.SetUsersConfiguration(linux.Useradd)
 	// ----- systemd -----------------------------------------------------------
 	systemd.Promise()
@@ -27,12 +28,12 @@ func Promise() {
 	gonf.AppendVariable("debian-extra-sources", "# Extra sources")
 	gonf.File("/etc/apt/sources.list").
 		Permissions(rootRO).
-		Template(sources_list).
+		Template(sourcesList).
 		Promise().
-		IfRepaired(apt_update)
+		IfRepaired(aptUpdate)
 	gonf.File("/etc/apt/apt.conf.d/99_norecommends").
 		DirectoriesPermissions(rootDir).
 		Permissions(rootRO).
-		Contents(apt_norecommends).
+		Contents(aptNoRecommends).
 		Promise()
 }
diff --git a/stdlib/os/systemd/systemd.go b/stdlib/os/systemd/systemd.go
index 8d5ec77..81e6a6b 100644
--- a/stdlib/os/systemd/systemd.go
+++ b/stdlib/os/systemd/systemd.go
@@ -8,7 +8,7 @@ import (
 )
 
 func Promise() {
-	gonf.SetServiceFunction(systemd_service)
+	gonf.SetServiceFunction(systemdService)
 }
 
 func isEnabled(name string) bool {
@@ -33,7 +33,7 @@ func systemctlShow(name, field string) string {
 	return string(out[:len(out)-1]) // remove trailing '\n' and convert to string
 }
 
-func systemd_service(name, state string) (gonf.Status, error) {
+func systemdService(name, state string) (gonf.Status, error) {
 	switch state {
 	case "disabled":
 		if isEnabled(name) {