simple_form default for @as overrides form values #5901
Description
While using the simple_form component (that is generated by default using mix phx.new), the following problem grabbed my attention. I was building a form schema inside a live view and wanted to render that form using the simple_form component.
The example states that it should be used like this
<.simple_form for={@form} phx-change="validate" phx-submit="save">
<.input field={@form[:email]} label="Email"/>
<.input field={@form[:username]} label="Username" />
<:actions>
<.button>Save</.button>
</:actions>
</.simple_form>
But I thought, that it would be more consistent to use the <.simple_form :let={f} for={@form}> in my case (because I was likely to also use inputs_for in that project). But using :let does cause the struct f to contain nil as it's name, which in turn messes up the field names and value groupings of the form (as the prefix based on the schema name is missing).
Currently, the following code:
defmodule HelloWeb.SimpleFormLetBindingLive do
use HelloWeb, :live_view
defmodule FormSchema do
use Ecto.Schema
import Ecto.Changeset
@primary_key false
embedded_schema do
field(:foo, :string)
field(:bar, :string)
end
def changeset(data, attrs) do
data
|> cast(attrs, [:foo, :bar])
|> validate_required([:foo, :bar])
end
end
@impl Phoenix.LiveView
def handle_params(_, _, socket) do
form = to_form(FormSchema.changeset(%FormSchema{}, %{}))
socket = assign(socket, form: form)
{:noreply, socket}
end
@impl Phoenix.LiveView
def render(assigns) do
~H"""
<.simple_form :let={f} for={@form}>
<table>
<tr>
<th><code>@form.name</code></th>
<td><code><%= inspect(@form.name) %></code></td>
</tr>
<tr>
<th><code>f.name</code></th>
<td><code><%= inspect(f.name) %></code></td>
</tr>
</table>
<.input field={@form[:foo]} label="Foo" />
<.input field={f[:bar]} label="Bar" />
</.simple_form>
"""
end
end
produces the following results
Which seems odd to me.
I prepared an example repository that can be used to reproduce the issue.