Phoenix.LiveViewTest.follow_trigger_action

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Link to this macro

follow_trigger_action(form, conn)

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Receives a form_element and asserts that phx-trigger-action has been set to true, following up on that request.

Imagine you have a LiveView that sends an HTTP form submission. Say that it sets the phx-trigger-action to true, as a response to a submit event. You can follow the trigger action like this:

form = form(live_view, selector, %{"form" => "data"})

# First we submit the form. Optionally verify that phx-trigger-action
# is now part of the form.
assert render_submit(form) =~ ~r/phx-trigger-action/

# Now follow the request made by the form
conn = follow_trigger_action(form, conn)
assert conn.method == "POST"
assert conn.params == %{"form" => "data"}