Remove Ecto references from AGENTS.md for --no-ecto projects

Author: bmalum

installer/test/phx_new_test.exs

@@ -555,6 +555,12 @@ defmodule Mix.Tasks.Phx.NewTest do
         assert file =~ "inputs: [\"*.{heex,ex,exs}\", \"{config,lib,test}/**/*.{heex,ex,exs}\"]"
         refute file =~ "subdirectories:"
       end)
+
+      assert_file("phx_blog/AGENTS.md", fn file ->
+        refute file =~ "Ecto"
+        refute file =~ "changeset"
+        refute file =~ "Ecto.Schema"
+      end)
     end)
   end
 

usage-rules/ecto.md

@@ -7,3 +7,26 @@
 - You **must** use `Ecto.Changeset.get_field(changeset, :field)` to access changeset fields
 - Fields which are set programatically, such as `user_id`, must not be listed in `cast` calls or similar for security purposes. Instead they must be explicitly set when creating the struct
 - **Always** invoke `mix ecto.gen.migration migration_name_using_underscores` when generating migration files, so the correct timestamp and conventions are applied
+
+### Creating LiveView forms from changesets
+
+When using changesets with LiveView, the underlying data, form params, and errors are retrieved from it. The `:as` option is automatically computed too. E.g. if you have a user schema:
+
+    defmodule MyApp.Users.User do
+      use Ecto.Schema
+      ...
+    end
+
+And then you create a changeset that you pass to `to_form`:
+
+    %MyApp.Users.User{}
+    |> Ecto.Changeset.change()
+    |> to_form()
+
+Once the form is submitted, the params will be available under `%{"user" => user_params}`.
+
+In the template, the form assign can be passed to the `<.form>` function component:
+
+    <.form for={@form} id="todo-form" phx-change="validate" phx-submit="save">
+      <.input field={@form[:field]} type="text" />
+    </.form>

usage-rules/elixir.md

@@ -29,7 +29,7 @@
         end
 
 - **Never** nest multiple modules in the same file as it can cause cyclic dependencies and compilation errors
-- **Never** use map access syntax (`changeset[:field]`) on structs as they do not implement the Access behaviour by default. For regular structs, you **must** access the fields directly, such as `my_struct.field` or use higher level APIs that are available on the struct if they exist, `Ecto.Changeset.get_field/2` for changesets
+- **Never** use map access syntax on structs as they do not implement the Access behaviour by default. For structs, you **must** access the fields directly, such as `my_struct.field` or use higher level APIs that are available on the struct if they exist
 - Elixir's standard library has everything necessary for date and time manipulation. Familiarize yourself with the common `Time`, `Date`, `DateTime`, and `Calendar` interfaces by accessing their documentation as necessary. **Never** install additional dependencies unless asked or for date/time parsing (which you can use the `date_time_parser` package)
 - Don't use `String.to_atom/1` on user input (memory leak risk)
 - Predicate function names should not start with `is_` and should end in a question mark. Names like `is_thing` should be reserved for guards

usage-rules/liveview.md

@@ -186,29 +186,6 @@ You can also specify a name to nest the params:
       {:noreply, assign(socket, form: to_form(user_params, as: :user))}
     end
 
-#### Creating a form from changesets
-
-When using changesets, the underlying data, form params, and errors are retrieved from it. The `:as` option is automatically computed too. E.g. if you have a user schema:
-
-    defmodule MyApp.Users.User do
-      use Ecto.Schema
-      ...
-    end
-
-And then you create a changeset that you pass to `to_form`:
-
-    %MyApp.Users.User{}
-    |> Ecto.Changeset.change()
-    |> to_form()
-
-Once the form is submitted, the params will be available under `%{"user" => user_params}`.
-
-In the template, the form form assign can be passed to the `<.form>` function component:
-
-    <.form for={@form} id="todo-form" phx-change="validate" phx-submit="save">
-      <.input field={@form[:field]} type="text" />
-    </.form>
-
 Always give the form an explicit, unique DOM ID, like `id="todo-form"`.
 
 #### Avoiding form errors
@@ -223,9 +200,8 @@ Always give the form an explicit, unique DOM ID, like `id="todo-form"`.
 And **never** do this:
 
     <%!-- NEVER do this (invalid) --%>
-    <.form for={@changeset} id="my-form">
-      <.input field={@changeset[:field]} type="text" />
+    <.form for={@data} id="my-form">
+      <.input field={@data[:field]} type="text" />
     </.form>
 
-- You are FORBIDDEN from accessing the changeset in the template as it will cause errors
-- **Never** use `<.form let={f} ...>` in the template, instead **always use `<.form for={@form} ...>`**, then drive all form references from the form assign as in `@form[:field]`. The UI should **always** be driven by a `to_form/2` assigned in the LiveView module that is derived from a changeset
+- **Never** use `<.form let={f} ...>` in the template, instead **always use `<.form for={@form} ...>`**, then drive all form references from the form assign as in `@form[:field]`. The UI should **always** be driven by a `to_form/1` or `to_form/2` assigned in the LiveView module