wwctl node args and completions

Signed-off-by: Jonathon Anderson <janderson@ciq.com>

internal/app/wwctl/completions/completions.go

@@ -7,6 +7,7 @@ import (
 	"github.com/warewulf/warewulf/internal/pkg/image"
 	"github.com/warewulf/warewulf/internal/pkg/kernel"
 	"github.com/warewulf/warewulf/internal/pkg/node"
+	"github.com/warewulf/warewulf/internal/pkg/overlay"
 )
 
 func NodeKernelVersion(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
@@ -51,18 +52,37 @@ func ProfileKernelVersion(cmd *cobra.Command, args []string, toComplete string)
 func Images(num int) func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 	return func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
 		if num <= 0 || len(args) < num {
-			sources, _ := image.ListSources()
-			return sources, cobra.ShellCompDirectiveNoFileComp
-		} else {
-			return nil, cobra.ShellCompDirectiveNoFileComp
+			if sources, err := image.ListSources(); err != nil {
+				return sources, cobra.ShellCompDirectiveNoFileComp
+			}
 		}
+		return nil, cobra.ShellCompDirectiveNoFileComp
 	}
 }
 
-func Profiles(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-	if len(args) != 0 {
+func Nodes(num int) func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+	return func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+		if num <= 0 || len(args) < num {
+			if registry, err := node.New(); err == nil {
+				return registry.ListAllNodes(), cobra.ShellCompDirectiveNoFileComp
+			}
+		}
 		return nil, cobra.ShellCompDirectiveNoFileComp
 	}
-	registry, _ := node.New()
-	return registry.ListAllProfiles(), cobra.ShellCompDirectiveNoFileComp
+}
+
+func Profiles(num int) func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+	return func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+		if num <= 0 || len(args) < num {
+			if registry, err := node.New(); err == nil {
+				return registry.ListAllProfiles(), cobra.ShellCompDirectiveNoFileComp
+			}
+		}
+		return nil, cobra.ShellCompDirectiveNoFileComp
+	}
+}
+
+func Overlays(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
+	list := overlay.FindOverlays()
+	return list, cobra.ShellCompDirectiveNoFileComp
 }

internal/app/wwctl/node/add/root.go

@@ -1,14 +1,10 @@
 package add
 
 import (
-	"log"
-
 	"github.com/spf13/cobra"
 	"github.com/warewulf/warewulf/internal/app/wwctl/completions"
 	"github.com/warewulf/warewulf/internal/app/wwctl/flags"
-	"github.com/warewulf/warewulf/internal/pkg/image"
 	"github.com/warewulf/warewulf/internal/pkg/node"
-	"github.com/warewulf/warewulf/internal/pkg/overlay"
 )
 
 // Holds the variables which are needed in CobraRunE
@@ -29,42 +25,26 @@ func GetCommand() *cobra.Command {
 		Aliases:               []string{"new", "create"},
 		RunE:                  CobraRunE(&vars),
 		Args:                  cobra.MinimumNArgs(1),
+		ValidArgsFunction:     cobra.FixedCompletions(nil, cobra.ShellCompDirectiveNoFileComp),
 	}
 	vars.nodeConf.CreateFlags(baseCmd)
 	vars.nodeAdd.CreateAddFlags(baseCmd)
 	flags.AddContainer(baseCmd, &(vars.nodeConf.Profile.ImageName))
 	// register the command line completions
-	if err := baseCmd.RegisterFlagCompletionFunc("image", func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		list, _ := image.ListSources()
-		return list, cobra.ShellCompDirectiveNoFileComp
-	}); err != nil {
-		log.Println(err)
+	if err := baseCmd.RegisterFlagCompletionFunc("image", completions.Images(0)); err != nil { // no limit
+		panic(err)
 	}
 	if err := baseCmd.RegisterFlagCompletionFunc("kernelversion", completions.NodeKernelVersion); err != nil {
-		log.Println(err)
+		panic(err)
 	}
-	if err := baseCmd.RegisterFlagCompletionFunc("runtime", func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		list := overlay.FindOverlays()
-		return list, cobra.ShellCompDirectiveNoFileComp
-	}); err != nil {
-		log.Println(err)
+	if err := baseCmd.RegisterFlagCompletionFunc("runtime", completions.Overlays); err != nil {
+		panic(err)
 	}
-	if err := baseCmd.RegisterFlagCompletionFunc("wwinit", func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		list := overlay.FindOverlays()
-		return list, cobra.ShellCompDirectiveNoFileComp
-	}); err != nil {
-		log.Println(err)
+	if err := baseCmd.RegisterFlagCompletionFunc("wwinit", completions.Overlays); err != nil {
+		panic(err)
 	}
-	if err := baseCmd.RegisterFlagCompletionFunc("profile", func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		var list []string
-		nodeDB, _ := node.New()
-		profiles, _ := nodeDB.FindAllProfiles()
-		for _, profile := range profiles {
-			list = append(list, profile.Id())
-		}
-		return list, cobra.ShellCompDirectiveNoFileComp
-	}); err != nil {
-		log.Println(err)
+	if err := baseCmd.RegisterFlagCompletionFunc("profile", completions.Profiles(0)); err != nil { // no limit
+		panic(err)
 	}
 
 	// GetRootCommand returns the root cobra.Command for the application.

internal/app/wwctl/node/console/root.go

@@ -2,6 +2,7 @@ package console
 
 import (
 	"github.com/spf13/cobra"
+	"github.com/warewulf/warewulf/internal/app/wwctl/completions"
 )
 
 var (
@@ -12,6 +13,7 @@ var (
 		Long:                  "Start a new IPMI console for NODENAME.",
 		Args:                  cobra.MinimumNArgs(1),
 		RunE:                  CobraRunE,
+		ValidArgsFunction:     completions.Nodes(0), // no limit
 	}
 )
 

internal/app/wwctl/node/delete/root.go

@@ -2,7 +2,7 @@ package delete
 
 import (
 	"github.com/spf13/cobra"
-	"github.com/warewulf/warewulf/internal/pkg/node"
+	"github.com/warewulf/warewulf/internal/app/wwctl/completions"
 )
 
 var (
@@ -14,15 +14,7 @@ var (
 		Args:                  cobra.MinimumNArgs(1),
 		RunE:                  CobraRunE,
 		Aliases:               []string{"rm", "del", "remove"},
-		ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-			if len(args) != 0 {
-				return nil, cobra.ShellCompDirectiveNoFileComp
-			}
-
-			nodeDB, _ := node.New()
-			nodes := nodeDB.ListAllNodes()
-			return nodes, cobra.ShellCompDirectiveNoFileComp
-		},
+		ValidArgsFunction:     completions.Nodes(0), // no limit
 	}
 	SetYes   bool
 	SetForce bool // no hash checking, so always using force

internal/app/wwctl/node/edit/main.go

@@ -7,6 +7,7 @@ import (
 	"strings"
 
 	"github.com/spf13/cobra"
+	"github.com/warewulf/warewulf/internal/pkg/hostlist"
 	"github.com/warewulf/warewulf/internal/pkg/node"
 	"github.com/warewulf/warewulf/internal/pkg/util"
 	"github.com/warewulf/warewulf/internal/pkg/warewulfd"
@@ -34,6 +35,8 @@ func CobraRunE(cmd *cobra.Command, args []string) error {
 		for nodeID := range registry.Nodes {
 			args = append(args, nodeID)
 		}
+	} else {
+		args = hostlist.Expand(args)
 	}
 	wwlog.Debug("node list: %v", args)
 

internal/app/wwctl/node/edit/root.go

@@ -2,7 +2,7 @@ package edit
 
 import (
 	"github.com/spf13/cobra"
-	"github.com/warewulf/warewulf/internal/pkg/node"
+	"github.com/warewulf/warewulf/internal/app/wwctl/completions"
 )
 
 var (
@@ -12,20 +12,7 @@ var (
 		Short:                 "Edit node(s) with editor",
 		Long:                  "This command opens an editor for the given nodes.",
 		RunE:                  CobraRunE,
-		ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-			if len(args) != 0 {
-				return nil, cobra.ShellCompDirectiveNoFileComp
-			}
-
-			nodeDB, _ := node.New()
-			nodes, _ := nodeDB.FindAllNodes()
-			var node_names []string
-			for _, node := range nodes {
-				node_names = append(node_names, node.Id())
-			}
-
-			return node_names, cobra.ShellCompDirectiveNoFileComp
-		},
+		ValidArgsFunction:     completions.Nodes(0), // no limit
 	}
 	NoHeader bool
 )

internal/app/wwctl/node/export/main.go

@@ -8,18 +8,10 @@ import (
 )
 
 func CobraRunE(cmd *cobra.Command, args []string) error {
-	if len(args) == 0 {
-		args = append(args, ".*")
-	}
 	filterList := wwapiv1.NodeList{
 		Output: args,
 	}
 	nodeListMsg := apinode.FilteredNodes(&filterList)
-	/*
-		nodeMap := make(map[string]*node.NodeConf)
-		// got proper yaml back
-		_ = yaml.Unmarshal([]byte(nodeListMsg.NodeConfMapYaml), nodeMap)
-	*/
 	wwlog.Info(nodeListMsg.NodeConfMapYaml)
 	return nil
 }

internal/app/wwctl/node/export/root.go

@@ -2,7 +2,7 @@ package export
 
 import (
 	"github.com/spf13/cobra"
-	"github.com/warewulf/warewulf/internal/pkg/node"
+	"github.com/warewulf/warewulf/internal/app/wwctl/completions"
 )
 
 var (
@@ -12,19 +12,7 @@ var (
 		Short:                 "Export nodes as yaml to stdout",
 		Long:                  "This command exports the given nodes as yaml to stdout.",
 		RunE:                  CobraRunE,
-		ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-			if len(args) != 0 {
-				return nil, cobra.ShellCompDirectiveNoFileComp
-			}
-
-			nodeDB, _ := node.New()
-			nodes, _ := nodeDB.FindAllNodes()
-			var node_names []string
-			for _, node := range nodes {
-				node_names = append(node_names, node.Id())
-			}
-			return node_names, cobra.ShellCompDirectiveNoFileComp
-		},
+		ValidArgsFunction:     completions.Nodes(0), // no limit
 	}
 	NoHeader bool
 )

internal/app/wwctl/node/imprt/root.go

@@ -13,7 +13,7 @@ var (
 		Short:                 "Import node(s) from yaml file",
 		Long:                  "This command imports all the nodes defined in a file. It will overwrite nodes with same name.",
 		RunE:                  CobraRunE,
-		Args:                  cobra.MinimumNArgs(1),
+		Args:                  cobra.ExactArgs(1),
 		Aliases:               []string{"import"},
 	}
 	ImportCVS bool

internal/app/wwctl/node/list/main.go

@@ -13,9 +13,6 @@ import (
 
 func CobraRunE(vars *variables) func(cmd *cobra.Command, args []string) (err error) {
 	return func(cmd *cobra.Command, args []string) (err error) {
-		if len(args) > 0 && strings.Contains(args[0], ",") {
-			args = strings.FieldsFunc(args[0], func(r rune) bool { return r == ',' })
-		}
 		req := wwapiv1.GetNodeList{
 			Nodes: args,
 			Type:  wwapiv1.GetNodeList_Simple,

internal/app/wwctl/node/list/root.go

@@ -2,7 +2,7 @@ package list
 
 import (
 	"github.com/spf13/cobra"
-	"github.com/warewulf/warewulf/internal/pkg/node"
+	"github.com/warewulf/warewulf/internal/app/wwctl/completions"
 )
 
 type variables struct {
@@ -22,21 +22,9 @@ func GetCommand() *cobra.Command {
 		Short:                 "List nodes",
 		Long: "This command lists all configured nodes. Optionally, it will list only\n" +
 			"nodes matching a PATTERN.",
-		RunE:    CobraRunE(&vars),
-		Aliases: []string{"ls"},
-		ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-			if len(args) != 0 {
-				return nil, cobra.ShellCompDirectiveNoFileComp
-			}
-
-			nodeDB, _ := node.New()
-			nodes, _ := nodeDB.FindAllNodes()
-			var node_names []string
-			for _, node := range nodes {
-				node_names = append(node_names, node.Id())
-			}
-			return node_names, cobra.ShellCompDirectiveNoFileComp
-		},
+		RunE:              CobraRunE(&vars),
+		Aliases:           []string{"ls"},
+		ValidArgsFunction: completions.Nodes(0), // no limit
 	}
 	baseCmd.PersistentFlags().BoolVarP(&vars.showNet, "net", "n", false, "Show node network configurations")
 	baseCmd.PersistentFlags().BoolVarP(&vars.showIpmi, "ipmi", "i", false, "Show node IPMI configurations")

internal/app/wwctl/node/sensors/root.go

@@ -2,7 +2,7 @@ package sensors
 
 import (
 	"github.com/spf13/cobra"
-	"github.com/warewulf/warewulf/internal/pkg/node"
+	"github.com/warewulf/warewulf/internal/app/wwctl/completions"
 )
 
 type variables struct {
@@ -21,19 +21,7 @@ func GetCommand() *cobra.Command {
 		Long:                  "Show IPMI sensor information for nodes matching PATTERN.",
 		Args:                  cobra.MinimumNArgs(1),
 		RunE:                  CobraRunE(&vars),
-		ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-			if len(args) != 0 {
-				return nil, cobra.ShellCompDirectiveNoFileComp
-			}
-
-			nodeDB, _ := node.New()
-			nodes, _ := nodeDB.FindAllNodes()
-			var node_names []string
-			for _, node := range nodes {
-				node_names = append(node_names, node.Id())
-			}
-			return node_names, cobra.ShellCompDirectiveNoFileComp
-		},
+		ValidArgsFunction:     completions.Nodes(0), // no limit
 	}
 	powerCmd.PersistentFlags().BoolVarP(&vars.Full, "full", "F", false, "show detailed output.")
 	powerCmd.PersistentFlags().BoolVarP(&vars.Showcmd, "show", "s", false, "only show command which will be executed")

internal/app/wwctl/node/set/root.go

@@ -1,14 +1,10 @@
 package set
 
 import (
-	"log"
-
 	"github.com/spf13/cobra"
 	"github.com/warewulf/warewulf/internal/app/wwctl/completions"
 	"github.com/warewulf/warewulf/internal/app/wwctl/flags"
-	"github.com/warewulf/warewulf/internal/pkg/image"
 	"github.com/warewulf/warewulf/internal/pkg/node"
-	"github.com/warewulf/warewulf/internal/pkg/overlay"
 )
 
 type variables struct {
@@ -31,15 +27,7 @@ func GetCommand() *cobra.Command {
 		Aliases:               []string{"modify"},
 		Args:                  cobra.MinimumNArgs(1), // require pattern as a mandatory arg
 		RunE:                  CobraRunE(&vars),
-		ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-			if len(args) != 0 {
-				return nil, cobra.ShellCompDirectiveNoFileComp
-			}
-
-			nodeDB, _ := node.New()
-			nodes := nodeDB.ListAllNodes()
-			return nodes, cobra.ShellCompDirectiveNoFileComp
-		},
+		ValidArgsFunction:     completions.Nodes(0), // no limit
 	}
 
 	vars.nodeConf.CreateFlags(baseCmd)
@@ -50,37 +38,20 @@ func GetCommand() *cobra.Command {
 	baseCmd.PersistentFlags().BoolVarP(&vars.setYes, "yes", "y", false, "Set 'yes' to all questions asked")
 	baseCmd.PersistentFlags().BoolVarP(&vars.setForce, "force", "f", false, "Force configuration (even on error)")
 	// register the command line completions
-	if err := baseCmd.RegisterFlagCompletionFunc("image", func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		list, _ := image.ListSources()
-		return list, cobra.ShellCompDirectiveNoFileComp
-	}); err != nil {
-		log.Println(err)
+	if err := baseCmd.RegisterFlagCompletionFunc("image", completions.Images(0)); err != nil { // no limit
+		panic(err)
 	}
 	if err := baseCmd.RegisterFlagCompletionFunc("kernelversion", completions.NodeKernelVersion); err != nil {
-		log.Println(err)
+		panic(err)
 	}
-	if err := baseCmd.RegisterFlagCompletionFunc("runtime", func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		list := overlay.FindOverlays()
-		return list, cobra.ShellCompDirectiveNoFileComp
-	}); err != nil {
-		log.Println(err)
+	if err := baseCmd.RegisterFlagCompletionFunc("runtime", completions.Overlays); err != nil {
+		panic(err)
 	}
-	if err := baseCmd.RegisterFlagCompletionFunc("wwinit", func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		list := overlay.FindOverlays()
-		return list, cobra.ShellCompDirectiveNoFileComp
-	}); err != nil {
-		log.Println(err)
+	if err := baseCmd.RegisterFlagCompletionFunc("wwinit", completions.Overlays); err != nil {
+		panic(err)
 	}
-	if err := baseCmd.RegisterFlagCompletionFunc("profile", func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
-		var list []string
-		nodeDB, _ := node.New()
-		profiles, _ := nodeDB.FindAllProfiles()
-		for _, profile := range profiles {
-			list = append(list, profile.Id())
-		}
-		return list, cobra.ShellCompDirectiveNoFileComp
-	}); err != nil {
-		log.Println(err)
+	if err := baseCmd.RegisterFlagCompletionFunc("profile", completions.Profiles(0)); err != nil { // no limit
+		panic(err)
 	}
 
 	return baseCmd

internal/app/wwctl/node/status/root.go

@@ -1,6 +1,9 @@
 package nodestatus
 
-import "github.com/spf13/cobra"
+import (
+	"github.com/spf13/cobra"
+	"github.com/warewulf/warewulf/internal/app/wwctl/completions"
+)
 
 var (
 	baseCmd = &cobra.Command{
@@ -9,7 +12,7 @@ var (
 		Short:                 "View the provisioning status of nodes",
 		Long:                  "View and monitor the status of nodes as they are provisioned and check in.",
 		RunE:                  CobraRunE,
-		Args:                  cobra.MinimumNArgs(0),
+		ValidArgsFunction:     completions.Nodes(0), // no limit
 	}
 	SetWatch       bool
 	SetUpdate      int

internal/pkg/hostlist/hostlist.go

@@ -4,77 +4,113 @@ import (
 	"fmt"
 	"strconv"
 	"strings"
-	"unicode"
 )
 
-func toInt(i string) int {
-	ret, _ := strconv.Atoi(i)
-	return ret
-}
-
-func isDigit(s string) bool {
-	r := []rune(s)
-
-	for i := 0; i < len(r); i++ {
-		if !unicode.IsDigit(r[i]) {
-			return false
-		}
-	}
-
-	return true
-}
-
-func expand_iterate(list []string) ([]string, int) {
-	var ret []string
-	var count int
-
-	for _, i := range list {
-
-		bracketIndex1 := strings.Index(i, "[")
-		bracketIndex2 := strings.Index(i, "]")
-
-		if bracketIndex1 >= 0 && bracketIndex1 < bracketIndex2 {
-			prefix := i[:bracketIndex1]
-			suffix := i[bracketIndex2+1:]
-			ranges := strings.Split(i[bracketIndex1+1:bracketIndex2], ",")
-			count++
-
-			for _, r := range ranges {
-				iterate := strings.Split(r, "-")
-
-				if len(iterate) == 1 {
-					if !isDigit(iterate[0]) {
-						return ret, 0
-					} else {
-						ret = append(ret, prefix+iterate[0]+suffix)
-					}
-				} else if len(iterate) == 2 {
-					if !isDigit(iterate[0]) || !isDigit(iterate[1]) {
-						return ret, 0
-					} else {
-						sigfigures := len(iterate[0])
-						for i := toInt(iterate[0]); i <= toInt(iterate[1]); i++ {
-							ret = append(ret, fmt.Sprintf(`%s%.`+fmt.Sprintf("%d", sigfigures)+`d%s`, prefix, i, suffix))
-						}
-					}
-				}
-			}
-		}
-	}
-	return ret, count
-}
-
+// Expand takes a slice of host strings, possibly containing comma-separated
+// values and bracketed ranges (e.g. "node[01-03]") and returns a fully expanded
+// slice of host names.
 func Expand(list []string) []string {
-	ret := list
+	// First, split each input string on commas that occur outside brackets.
+	var preList []string
+	for _, s := range list {
+		parts := splitTopLevel(s)
+		preList = append(preList, parts...)
+	}
 
+	expanded := preList
 	for {
-		loop, count := expand_iterate(ret)
-
+		onceExpanded, count := expandOnce(expanded)
 		if count == 0 {
 			break
 		}
-		ret = loop
+		expanded = onceExpanded
 	}
 
-	return ret
+	return expanded
+}
+
+// expandOnce performs a single round of bracket expansion.
+func expandOnce(hosts []string) ([]string, int) {
+	var result []string
+	var expansionCount int
+
+	for _, host := range hosts {
+		bracketStart := strings.Index(host, "[")
+		bracketEnd := strings.Index(host, "]")
+
+		if bracketStart >= 0 && bracketStart < bracketEnd {
+			prefix := host[:bracketStart]
+			suffix := host[bracketEnd+1:]
+			// Extract the content between brackets and split on commas.
+			ranges := strings.Split(host[bracketStart+1:bracketEnd], ",")
+			expansionCount++
+
+			for _, rng := range ranges {
+				parts := strings.Split(rng, "-")
+
+				if len(parts) == 1 {
+					if !isDigit(parts[0]) {
+						// Abort expansion on invalid input.
+						return result, 0
+					}
+					result = append(result, prefix+parts[0]+suffix)
+				} else if len(parts) == 2 {
+					if !isDigit(parts[0]) || !isDigit(parts[1]) {
+						return result, 0
+					}
+					sigFigures := len(parts[0])
+					startNum := toInt(parts[0])
+					endNum := toInt(parts[1])
+					for num := startNum; num <= endNum; num++ {
+						result = append(result, fmt.Sprintf("%s%0*d%s", prefix, sigFigures, num, suffix))
+					}
+				}
+			}
+		} else {
+			// No brackets; keep the string as is.
+			result = append(result, host)
+		}
+	}
+
+	return result, expansionCount
+}
+
+// splitTopLevel splits s on commas that are not inside square brackets.
+func splitTopLevel(s string) []string {
+	var parts []string
+	depth := 0
+	start := 0
+	for i, ch := range s {
+		switch ch {
+		case '[':
+			depth++
+		case ']':
+			if depth > 0 {
+				depth--
+			}
+		case ',':
+			if depth == 0 {
+				parts = append(parts, s[start:i])
+				start = i + 1
+			}
+		}
+	}
+	parts = append(parts, s[start:])
+	return parts
+}
+
+// toInt converts a numeric string to an integer. Assumes valid input.
+func toInt(s string) int {
+	num, _ := strconv.Atoi(s)
+	return num
+}
+
+// isDigit returns true if s consists solely of ASCII digits.
+func isDigit(s string) bool {
+	for i := 0; i < len(s); i++ {
+		if s[i] < '0' || s[i] > '9' {
+			return false
+		}
+	}
+	return true
 }

internal/pkg/hostlist/hostlist_test.go

@@ -6,28 +6,48 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func Test_Single(t *testing.T) {
-	assert.Equal(t, []string{"node1"}, Expand([]string{"node1"}))
-}
+func TestHostList(t *testing.T) {
+	tests := map[string]struct {
+		input  []string
+		output []string
+	}{
+		"single": {
+			input:  []string{"node1"},
+			output: []string{"node1"},
+		},
+		"multiple": {
+			input:  []string{"node1", "node2"},
+			output: []string{"node1", "node2"},
+		},
+		"range": {
+			input:  []string{"node[1-2]"},
+			output: []string{"node1", "node2"},
+		},
+		"internal comma": {
+			input:  []string{"node[1,2]"},
+			output: []string{"node1", "node2"},
+		},
+		"mixed range comma": {
+			input:  []string{"node[1,2-3]"},
+			output: []string{"node1", "node2", "node3"},
+		},
+		"external comma": {
+			input:  []string{"node1,node2"},
+			output: []string{"node1", "node2"},
+		},
+		"mixed external comma with range": {
+			input:  []string{"n[1-3],n5,n[7-8,10]"},
+			output: []string{"n1", "n2", "n3", "n5", "n7", "n8", "n10"},
+		},
+		"leading zeroes": {
+			input:  []string{"n[01-03]"},
+			output: []string{"n01", "n02", "n03"},
+		},
+	}
 
-func Test_Multiple(t *testing.T) {
-	assert.Equal(t, []string{"node1", "node2"}, Expand([]string{"node1", "node2"}))
+	for name, tt := range tests {
+		t.Run(name, func(t *testing.T) {
+			assert.Equal(t, tt.output, Expand(tt.input))
+		})
+	}
 }
-
-func Test_Range(t *testing.T) {
-	assert.Equal(t, []string{"node1", "node2"}, Expand([]string{"node[1-2]"}))
-}
-
-func Test_Internal_Comma(t *testing.T) {
-	assert.Equal(t, []string{"node1", "node2"}, Expand([]string{"node[1,2]"}))
-}
-
-func Test_Mixed_Range_Comma(t *testing.T) {
-	assert.Equal(t, []string{"node1", "node2", "node3"}, Expand([]string{"node[1,2-3]"}))
-}
-
-// not currently supported
-//
-// func Test_External_Comma(t *testing.T) {
-// 	assert.Equal(t, []string{"node1", "node2"}, Expand([]string{"node1,node2"}))
-// }