Setting your prompt to show the current topic

While giving the talk about mercurial tips & tricks I got a request on the tools I’m using to show the topic name in the prompt:

I achieved that by using starship which is a cross-shell prompt configurator that is really fast.

Here’s the configuration I am using (skipping the irrelevant parts):

add_newline = true

format = """

format = "( [ $branch](green))([:$topic](blue bold))"
disabled = false