Subcommand tree view

[wr1]

First concept for tree view, bit rough still.

• example 13 works as intended
• example 14 doesn't, requires explicit setting of Command and Group class to work

[dwreeves]

Thank you so much for this speedy PR and I'm super excited to get it in for 1.9.0.

It looks like the main test that is failing here is a test that asserts rich is never imported during normal CLI execution. Basically, when a user wants to run their program, when they are not rendering help text, rich should never be inside of sys.modules.

The reason we assert this is because importing rich slows down code execution by a few milliseconds, and increases the memory footprint. And we pride ourselves on doing the best we can to make sure we get in the way of code execution as little as possible 😄 See this:

(note: rich-click 1.9.0 is even better! because we found another optimization...)

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The way we get around this is through lazy imports, and you'll see examples of this throughout the code. A few examples:

Here is an example of a lazy import direct to rich:

https://github.com/ewels/rich-click/blob/b77ce9ebc11a59e9a547221ea0d2df74f82a8563/src/rich_click/rich_help_formatter.py#L40-L52

This example here is a lazy import to the rich_help_rendering module. The rich_help_rendering module eagerly loads rich but the module itself is never eagerly loaded.

https://github.com/ewels/rich-click/blob/b77ce9ebc11a59e9a547221ea0d2df74f82a8563/src/rich_click/rich_command.py#L265-L268

[dwreeves]

Hi,

Some slightly bad news. I don't think we can get this in for 1.9. There's just too much work to do cleaning up 1.9 and getting this ready will take up too much additional time.

But, --tree will definitely be one of the bigger features for a 1.10 release!

Thank you a ton for your work on this. Please keep this PR open and we'll work on integrating it at some point in the near to medium term future, and it will get its own release.