first commit status: option and argument parsing, short aliases grouping, special values, hidden options

Option types: bool int, int-array, string, string-array, string-map, file, dir
2025-12-11 07:57:48 +01:00
parent b9a4efc956
commit 38e36839f8
22 changed files with 1604 additions and 0 deletions
@@ -0,0 +1,86 @@
+package cli
+
+import (
+	"fmt"
+	"os"
+	"strings"
+)
+
+// Usage()
+func (cli *CliParser) Usage() string {
+	var sb strings.Builder
+
+	program, _ := cli.GetVersionSection("program")
+	publicCount := cli.publicOptionCount()
+	if publicCount > 0 {
+		fmt.Fprintf(&sb, "USAGE: %s [<options>] %s\n", program, cli.getArgsTemplate())
+	} else {
+		fmt.Fprintf(&sb, "USAGE: %s %s\n", program, cli.getArgsTemplate())
+	}
+
+	if len(cli.argSpecs) > 0 || len(cli.options) > 0 {
+		fmt.Fprintf(&sb, "where:\n")
+		if len(cli.argSpecs) > 0 {
+			for _, argSpec := range cli.argSpecs {
+				arg := argSpec.getBase()
+				fmt.Fprintf(&sb, "  <%s>  %s\n", arg.name, arg.description)
+			}
+		}
+		if publicCount > 0 {
+			fmt.Fprintf(&sb, "  <options>\n")
+			templates, maxWidth := cli.makeOptionTemplateList()
+			for i, opti := range cli.options {
+				if opti.isHidden() {
+					continue
+				}
+				opt := opti.getBase()
+				aliases := opt.aliases
+				if len(aliases) > 0 && opt.isArray {
+					// Skip the last alias because it is the implicit plural alias
+					aliases = aliases[0 : len(aliases)-1]
+				}
+				if len(aliases) > 0 {
+					fmt.Fprintf(&sb, "    %-*s  %s (alias: %s)", maxWidth, templates[i], opt.description, strings.Join(aliases, ", "))
+				} else {
+					fmt.Fprintf(&sb, "    %-*s  %s", maxWidth, templates[i], opt.description)
+				}
+				if value := opti.getDefaultValue(); value != "" {
+					fmt.Fprintf(&sb, " (default: %q)", value)
+				}
+				sb.WriteByte('\n')
+			}
+		}
+	}
+	return sb.String()
+}
+
+func (cli *CliParser) publicOptionCount() (count int) {
+	for _, opti := range cli.options {
+		opt := opti.getBase()
+		if !opt.hidden {
+			count++
+		}
+	}
+	return
+}
+
+func (cli *CliParser) makeOptionTemplateList() (templates []string, maxWidth int) {
+	maxWidth = 0
+	templates = make([]string, len(cli.options))
+	for i, opti := range cli.options {
+		if opti.isHidden() {
+			templates[i] = ""
+		} else {
+			templates[i] = opti.getTemplate()
+			if len(templates[i]) > maxWidth {
+				maxWidth = len(templates[i])
+			}
+		}
+	}
+	return templates, maxWidth
+}
+
+// PrintUsage()
+func (cli *CliParser) PrintUsage() {
+	os.Stdout.WriteString(cli.Usage())
+}