Suggestion: add a some test utilities.

[Gladear]

At times, I want to test my generated HTML pretty extensively.

LazyHTML already makes it possible, but having some test utility functions would be welcome - either in a dedicated module, or directly in the main LazyHTML module, that I do not know.

The two examples that come to my mind right now would be

• a matches?(doc, selector) function, that basically corresponds to doc |> LazyHTML.filter(selector) |> Enum.empty?() |> Kernel.not()
• a exists?(doc, selector) function, that simplifies doc |> LazyHTML.query(selector) |> Enum.empty?() |> Kernel.not()

--
Now that I see it this way, maybe a LazyHTML.exists?(doc) that just verifies that a query or filter returned an element would be nice 😄

[jonatanklosko]

I would say a dedicates test-oriented module is outside the scope of this library. And I would avoid inflating the API with functions like matches? and exists? above, which are straightforward enough to have them as helpers in your tests for convenience.

The primary use of lazy_html is Phoenix.LiveViewTest, which implements all kinds of assertions.

@josevalim wdyt?

[josevalim]

I am not against new selectors, exactly because the ones above can be optimized to not allocate anything. But I’d say the difference between matches? and exists? above is a bit confusing. :)

[Gladear]

The name matches? comes from the JavaScript API: https://developer.mozilla.org/en-US/docs/Web/API/Element/matches
For exists? however, there is no inspiration but me trying to find a way to say "not empty" 😄