[TwigComponent] Document about unwanted behavior with ExposeInTemplate and computed methods

[Kocal]

Q	A
Bug fix?	no
New feature?	no
Issues	Fix #...
License	MIT

As spotted when working on my application, the following code triggers two times the methods transactions() because of the presence of #[ExposeInTemplate] (because before I used transactions instead of computed.transactions):

	#[ExposeInTemplate]
    public function transactions(): array
    {
        // SQL query to database
    }

{{ computed.transactions|length }}

When I remove #[ExposeInTemplate], then only one SQL query is made.

[smnandre]

Nothing illogical to me, but a mention in documentation won't hurt and clarify this case. 👍

Could you maybe use a "tip" block instead of a "warning" one here ?

[smnandre]

It kinda leads to present it as a bug... but it is not illogical.

The calls are not made at the same time so the "twice" is maybe a bit missleading
(first time to build the context of the templates, before render, and one by you calling the cache object).

[Kocal]

Do you think instead, we should fix this behavior?

I mean, throw an exception if the user tries to call a computed method with #[ExposeInTemplate] ?

[smnandre]

I am not sure we can. BUT we can maybe populate the computed before the render if method as the attribute. There are some limitations but this could work.

Lets update doc for now and see after if we change and how wdyt ?

(but id rather not use warning or any tone that can stress or frighten users 😇)

[smnandre]

We may want to make all these more clear with schema later..

But this precision is usefull right now, thx!