Deep copy cobra command tree that is remapped

Clone Command node involved in a remap along with all its descendent
commands. This ensures that the markdown documents generated from the
cloned nodes are consistent and reflect the remap, but does not
introduce inconsistencies in the existing nodes.

Signed-off-by: Vui Lam <vui.lam@broadcom.com>

plugin/generate_docs.go

@@ -67,6 +67,39 @@ func mapCommand(tanzuCmd, subCommand *cobra.Command, mapEntry *CommandMapEntry)
 	}
 }
 
+func cloneChildCommands(parentCloneCmd *cobra.Command) {
+	childCommands := parentCloneCmd.Commands()
+	for _, child := range childCommands {
+		newChild := *child
+		cloneChildCommands(&newChild)
+		childParent := child.Parent()
+		// child's parent pointer is wrong (still point to childParent, the
+		// source that parentCloneCmd is cloned from), so remove said child
+		parentCloneCmd.RemoveCommand(child)
+		// and add the properly updated clone of child instead
+		parentCloneCmd.AddCommand(&newChild)
+		// however, the removal has the side-effect of wiping the child's
+		// parent link, so remove then re-add back as child of the clone source
+		childParent.RemoveCommand(child)
+		childParent.AddCommand(child)
+
+		// there is currently no way to obtain the current help command so
+		// check the .Use field instead
+		// failure to update the help command to the clone will result in md
+		// generated for the clone (tanzu_xxx_help.md), something that is
+		// extraneous but not incorrect.
+		if child.Use == "help [command]" {
+			parentCloneCmd.SetHelpCommand(&newChild)
+		}
+	}
+}
+
+func deepCopy(cmd *cobra.Command) *cobra.Command {
+	clone := *cmd
+	cloneChildCommands(&clone)
+	return &clone
+}
+
 // rebuildTanzuCommandTree reconstructs the tanzu CLI's placement of the
 // plugin's commands after accounting for the plugin descriptor's CommandMap.
 // It is primarily used to prep a Command tree for cobra's doc generation APIs
@@ -86,7 +119,13 @@ func rebuildTanzuCommandTree(tanzuCmd, pluginRootCmd *cobra.Command, desc *Plugi
 	for _, v := range cmap {
 		mapEntry := v
 		cmd, _ := findSubCommandByHierarchy(pluginRootCmd, hierarchyFromPath(mapEntry.SourceCommandPath), matchOnCommandName)
-		mapCommand(tanzuCmd, cmd, &mapEntry)
+		copyOfCmd := deepCopy(cmd)
+		mapCommand(tanzuCmd, copyOfCmd, &mapEntry)
+		if cmd == pluginRootCmd {
+			// if this is a plugin level mapping, assume that the original
+			// plugin's command tree should not be made available anymore
+			cmd.Hidden = true
+		}
 	}
 }