improvement: add support for target and only_touched? validate opts

chore: update elixir/erlang versions

.tool-versions

@@ -1,2 +1,2 @@
-erlang 25.2.2
-elixir 1.14.3
+erlang 26.0.2
+elixir 1.15.4

lib/ash_phoenix/form/form.ex

@@ -856,6 +856,15 @@ defmodule AshPhoenix.Form do
       type: :boolean,
       default: true,
       doc: "Set to false to hide errors after validation"
+    ],
+    target: [
+      type: {:list, :string},
+      doc: "The `_target` param provided by phoenix. Used to support the `only_touched?` option."
+    ],
+    only_touched?: [
+      type: :boolean,
+      default: false,
+      doc: "If set to true, only fields that have been marked as touched will be used"
     ]
   ]
 
@@ -876,7 +885,32 @@ defmodule AshPhoenix.Form do
     |> Phoenix.HTML.FormData.to_form(form.options)
   end
 
-  def validate(form, new_params, opts) do
+  def validate(%{name: name} = form, new_params, opts) do
+    form =
+      case opts[:target] do
+        [^name | target] ->
+          field = List.last(target)
+          path = :lists.droplast(target)
+
+          case path do
+            [] ->
+              touch(form, field)
+
+            path ->
+              update_form(form, path, &touch(&1, field))
+          end
+
+        _ ->
+          form
+      end
+
+    new_params =
+      if opts[:only_touched?] do
+        Map.take(new_params, form.touched_forms)
+      else
+        new_params
+      end
+
     opts = validate_opts_with_extra_keys(opts, @validate_opts)
 
     prepare_source = form.prepare_source || (& &1)

test/form_test.exs

@@ -193,7 +193,10 @@ defmodule AshPhoenix.FormTest do
 
   test "blank form values unset - helps support dead view forms" do
     form =
-      Form.for_create(PostWithDefault, :create, api: Api, exclude_fields_if_empty: [:text, :title])
+      Form.for_create(PostWithDefault, :create,
+        api: Api,
+        exclude_fields_if_empty: [:text, :title]
+      )
 
     {:ok, post} = Form.submit(form, params: %{"title" => "", "text" => "bar"})
     assert post.text == "bar"