Support skip nil for cache fetch (#25437)

* test case for fetch cache miss with skip_nil

* abondon nil cache if skip_nil specified

* ensure not cache key for skip nil

* add document with skip_nil for Store#fetch

* add a new change log entry for #25437

1 files changed, 7 insertions, 0 deletions

diff --git a/activesupport/test/cache/behaviors/cache_store_behavior.rb b/activesupport/test/cache/behaviors/cache_store_behavior.rb
index f9153ffe2a..ae272e87d7 100644
--- a/activesupport/test/cache/behaviors/cache_store_behavior.rb
+++ b/activesupport/test/cache/behaviors/cache_store_behavior.rb
@@ -52,6 +52,13 @@ module CacheStoreBehavior
     end
   end
 
+  def test_fetch_cache_miss_with_skip_nil
+    assert_not_called(@cache, :write) do
+      assert_nil @cache.fetch("foo", skip_nil: true) { nil }
+      assert_equal false, @cache.exist?("foo")
+    end
+  end
+
   def test_fetch_with_forced_cache_miss_with_block
     @cache.write("foo", "bar")
     assert_equal "foo_bar", @cache.fetch("foo", force: true) { "foo_bar" }