improvement: Document :params option for for_action (#361)

Author: iyjim

lib/ash_phoenix/form/form.ex

@@ -285,6 +285,13 @@ defmodule AshPhoenix.Form do
     tenant: [
       type: :any,
       doc: "The current tenant. Passed through to the underlying action."
+    ],
+    params: [
+      type: :any,
+      default: %{},
+      doc: """
+      The initial parameters to use for the form. This is useful for setting up a form with default values.
+      """
     ]
   ]
 

test/form_test.exs

@@ -20,10 +20,19 @@ defmodule AshPhoenix.FormTest do
 
       assert 0 =
                Post
-               |> Form.for_action(:post_count, params: params)
+               |> Form.for_action(:post_count)
                |> Form.validate(params)
                |> Form.submit!(params: params)
     end
+
+    test "generic actions can accept initial params" do
+      params = %{containing: "hello"}
+
+      assert 0 =
+               Post
+               |> Form.for_action(:post_count, params: params)
+               |> Form.submit!(params: nil)
+    end
   end
 
   describe "drop_param" do