Fix: setting board entropy was changing the account entropy when not present

app/controllers/boards/entropies_controller.rb

@@ -4,7 +4,7 @@ class Boards::EntropiesController < ApplicationController
   before_action :ensure_permission_to_admin_board
 
   def update
-    @board.entropy.update!(entropy_params)
+    @board.update!(entropy_params)
   end
 
   private

test/controllers/boards/entropies_controller_test.rb

@@ -7,11 +7,13 @@ class Boards::EntropiesControllerTest < ActionDispatch::IntegrationTest
   end
 
   test "update" do
-    put board_entropy_path(@board, format: :turbo_stream), params: { board: { auto_postpone_period: 1.day } }
+    assert_no_difference -> { Account.sole.entropy.reload.auto_postpone_period } do
+      put board_entropy_path(@board, format: :turbo_stream), params: { board: { auto_postpone_period: 123.days } }
 
-    assert_equal 1.day, @board.entropy.reload.auto_postpone_period
+      assert_equal 123.days, @board.entropy.reload.auto_postpone_period
 
-    assert_turbo_stream action: :replace, target: dom_id(@board, :entropy)
+      assert_turbo_stream action: :replace, target: dom_id(@board, :entropy)
+    end
   end
 
   test "update requires board admin permission" do

test/models/card/entropic_test.rb

@@ -22,6 +22,16 @@ class Card::EntropicTest < ActiveSupport::TestCase
     assert_equal (123 - 2).days.from_now, cards(:layout).entropy.auto_clean_at
   end
 
+  test "setting auto_postpone_period in the board without entropy will create it, without affecting the account entropy" do
+    account_entropy = entropies("37s_account")
+    original_period = account_entropy.auto_postpone_period
+
+    entropies(:writebook_board).destroy
+    boards(:writebook).update! auto_postpone_period: 999.days
+
+    assert_equal original_period, account_entropy.reload.auto_postpone_period
+  end
+
   test "auto postpone all due using the default account entropy" do
     entropies(:writebook_board).destroy