12876: List subcommands like "arvados-client keep get" in main usage.

Arvados-DCO-1.1-Signed-off-by: Tom Clegg <tclegg@veritasgenetics.com>

diff --git a/lib/cmd/cmd.go b/lib/cmd/cmd.go
index d04006586f307ee4636ebabfbaaae8c084654480..2cc71e68a8e749e76d558b6c98e9e2c26a23f2db 100644 (file)
--- a/lib/cmd/cmd.go
+++ b/lib/cmd/cmd.go
@@ -56,6 +56,11 @@ func (m Multi) RunCommand(prog string, args []string, stdin io.Reader, stdout, s
 }
 
 func (m Multi) Usage(stderr io.Writer) {
+       fmt.Fprintf(stderr, "\nAvailable commands:\n")
+       m.listSubcommands(stderr, "")
+}
+
+func (m Multi) listSubcommands(out io.Writer, prefix string) {
        var subcommands []string
        for sc := range m {
                if strings.HasPrefix(sc, "-") {
@@ -67,9 +72,13 @@ func (m Multi) Usage(stderr io.Writer) {
                subcommands = append(subcommands, sc)
        }
        sort.Strings(subcommands)
-       fmt.Fprintf(stderr, "\nAvailable commands:\n")
        for _, sc := range subcommands {
-               fmt.Fprintf(stderr, "    %s\n", sc)
+               switch cmd := m[sc].(type) {
+               case Multi:
+                       cmd.listSubcommands(out, prefix+sc+" ")
+               default:
+                       fmt.Fprintf(out, "    %s%s\n", prefix, sc)
+               }
        }
 }