Vendor temporarily

vendor/github.com/mitchellh/cli/help.go

@@ -0,0 +1,79 @@
+package cli
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	"sort"
+	"strings"
+)
+
+// HelpFunc is the type of the function that is responsible for generating
+// the help output when the CLI must show the general help text.
+type HelpFunc func(map[string]CommandFactory) string
+
+// BasicHelpFunc generates some basic help output that is usually good enough
+// for most CLI applications.
+func BasicHelpFunc(app string) HelpFunc {
+	return func(commands map[string]CommandFactory) string {
+		var buf bytes.Buffer
+		buf.WriteString(fmt.Sprintf(
+			"Usage: %s [--version] [--help] <command> [<args>]\n\n",
+			app))
+		buf.WriteString("Available commands are:\n")
+
+		// Get the list of keys so we can sort them, and also get the maximum
+		// key length so they can be aligned properly.
+		keys := make([]string, 0, len(commands))
+		maxKeyLen := 0
+		for key := range commands {
+			if len(key) > maxKeyLen {
+				maxKeyLen = len(key)
+			}
+
+			keys = append(keys, key)
+		}
+		sort.Strings(keys)
+
+		for _, key := range keys {
+			commandFunc, ok := commands[key]
+			if !ok {
+				// This should never happen since we JUST built the list of
+				// keys.
+				panic("command not found: " + key)
+			}
+
+			command, err := commandFunc()
+			if err != nil {
+				log.Printf("[ERR] cli: Command '%s' failed to load: %s",
+					key, err)
+				continue
+			}
+
+			key = fmt.Sprintf("%s%s", key, strings.Repeat(" ", maxKeyLen-len(key)))
+			buf.WriteString(fmt.Sprintf("    %s    %s\n", key, command.Synopsis()))
+		}
+
+		return buf.String()
+	}
+}
+
+// FilteredHelpFunc will filter the commands to only include the keys
+// in the include parameter.
+func FilteredHelpFunc(include []string, f HelpFunc) HelpFunc {
+	return func(commands map[string]CommandFactory) string {
+		set := make(map[string]struct{})
+		for _, k := range include {
+			set[k] = struct{}{}
+		}
+
+		filtered := make(map[string]CommandFactory)
+		for k, f := range commands {
+			if _, ok := set[k]; ok {
+				filtered[k] = f
+			}
+		}
+
+		return f(filtered)
+	}
+}