Merge pull request #18551 from aditya-kapoor/fix-frozen-hwia

Fix assignment for frozen value in HWIA

activesupport/CHANGELOG.md

@@ -1,3 +1,10 @@
+*   Duplicate frozen array when assigning it to a HashWithIndifferentAccess so
+    that it doesn't raise a `RuntimeError` when calling `map!` on it in `convert_value`.
+
+    Fixes #18550.
+
+    *Aditya Kapoor*
+
 *   Add missing time zone definitions for Russian Federation and sync them
     with `zone.tab` file from tzdata version 2014j (latest).
 

activesupport/lib/active_support/hash_with_indifferent_access.rb

@@ -267,7 +267,7 @@ module ActiveSupport
             value.nested_under_indifferent_access
           end
         elsif value.is_a?(Array)
-          unless options[:for] == :assignment
+          if options[:for] != :assignment || value.frozen?
             value = value.dup
           end
           value.map! { |e| convert_value(e, options) }

activesupport/test/hash_with_indifferent_access_test.rb

@@ -7,4 +7,11 @@ class HashWithIndifferentAccessTest < ActiveSupport::TestCase
     hash.reverse_merge! key: :new_value
     assert_equal :old_value, hash[:key]
   end
+
+  def test_frozen_value
+    value = [1, 2, 3].freeze
+    hash = {}.with_indifferent_access
+    hash[:key] = value
+    assert_equal hash[:key], value
+  end
 end