Function commandUsage

cli/usage.go:126–179

commandUsage adds the command usage info for the given commands to the given [strings.Builder]. It also takes the full name of our command as it appears in the terminal (cmdName), (eg: "core build"), and the name of the command we are running (eg: "build"). To be a command that is included in the u

(b *strings.Builder, cmdName string, cmd string, cmds ...*Cmd[T])

// generate usage for "mod init", "mod tidy", and "mod edit". This ensures
// that only relevant commands are shown in the usage.
func commandUsage[T any](b *strings.Builder, cmdName string, cmd string, cmds ...*Cmd[T]) {
	acmds := []*Cmd[T]{}           // actual commands we care about
	var rcmd *Cmd[T]               // root command
	cmdstrs := strings.Fields(cmd) // subcommand strings in passed command

	// need this label so that we can continue outer loop when we have non-matching cmdstr
outer:
	for _, c := range cmds {
		cstrs := strings.Fields(c.Name)   // subcommand strings in command we are checking
		if len(cstrs) != len(cmdstrs)+1 { // we must be one deeper
			continue
		}
		for i, cmdstr := range cmdstrs {
			if cmdstr != cstrs[i] { // every subcommand so far must match
				continue outer
			}
		}
		if c.Root {
			rcmd = c
		} else if c.Name != cmd { // if it is the same subcommand we are already on, we handle it above in main Usage
			acmds = append(acmds, c)
		}
	}

	if len(acmds) != 0 {
		b.WriteString(indent + logx.CmdColor(cmdName+" <subcommand> ") + logx.SuccessColor("[flags]\n"))
	}

	if rcmd != nil {
		b.WriteString(logx.TitleColor("\nDefault command:\n"))
		b.WriteString(indent + logx.CmdColor(rcmd.Name) + "\n" + indent + indent + strings.ReplaceAll(rcmd.Doc, "\n", "\n"+indent+indent) + "\n") // need to put two indents on every newline for formatting
	}

	if len(acmds) == 0 && cmd != "" { // nothing to do
		return
	}

	b.WriteString(logx.TitleColor("\nSubcommands:\n"))

	// if we are in root, we also add help
	if cmd == "" {
		b.WriteString(indent + logx.CmdColor("help") + "\n" + indent + indent + "Help shows usage information for a command\n")
	}

	for _, c := range acmds {
		b.WriteString(indent + logx.CmdColor(c.Name))
		if c.Doc != "" {
			// we only want the first paragraph of text for subcommand usage; after that is where more specific details can go
			doc, _, _ := strings.Cut(c.Doc, "\n\n")
			b.WriteString("\n" + indent + indent + strings.ReplaceAll(doc, "\n", "\n"+indent+indent)) // need to put two indents on every newline for formatting
		}
		b.WriteString("\n")
	}
}

// flagUsage adds the flag usage info for the given fields
// to the given [strings.Builder].