maildir block: add configuration "hide_if_total_is_zero"

[mervn]

It would be both consistent¹ and useful for maildir notifications to only appear when mail is present. I have not seen the source, but it should successfully return nothing if status = 0 and hide_if_total_is_zero = true.

¹ The github block has an identical configuration.

[MaxVerevkin]

You can achieve this by using range argument of the number formatter:

[[block]]
block = "maildir"
format = " $icon $status.eng(range:1..) |"

This may be added to the examples.

[mervn]

format = " $icon $status.eng(range:1..) |"

This is a solid workaround, but it does not work without $status.

I would like to avoid seeing the status count on the display.
Is there a way to hide $status permanently?

[MaxVerevkin]

Is there a way to hide $status permanently?

Not yet. I imagine adding an argument to not render a value, something like $icon $status.eng(range:1..,render:false)|. Would that work for you?

I would prefer it over "hide if zero" because it would solve this issue for all blocks at once.

[mervn]

something like $icon $status.eng(range:1..,render:false)|

I am very happy with this solution. It's consistent (.eng is being used
by the book) and general (as you've noted).

I assume .eng(render:false) will print "" rather than " ". If so, zero
complaints from me.