Use a bind param for `LIMIT` and `OFFSET`

We currently generate an unbounded number of prepared statements when
`limit` or `offset` are called with a dynamic argument. This changes
`LIMIT` and `OFFSET` to use bind params, eliminating the problem.

`Type::Value#hash` needed to be implemented, as it turns out we busted
the query cache if the type object used wasn't exactly the same object.

This drops support for passing an `Arel::Nodes::SqlLiteral` to `limit`.
Doing this relied on AR internals, and was never officially supported
usage.

Fixes #22250.

2 files changed, 3 insertions, 9 deletions

diff --git a/activerecord/test/cases/base_test.rb b/activerecord/test/cases/base_test.rb
index b449280fb4..dc555caaff 100644
--- a/activerecord/test/cases/base_test.rb
+++ b/activerecord/test/cases/base_test.rb
@@ -147,12 +147,6 @@ class BasicsTest < ActiveRecord::TestCase
     end
   end
 
-  unless current_adapter?(:MysqlAdapter, :Mysql2Adapter)
-    def test_limit_should_allow_sql_literal
-      assert_equal 1, Topic.limit(Arel.sql('2-1')).to_a.length
-    end
-  end
-
   def test_select_symbol
     topic_ids = Topic.select(:id).map(&:id).sort
     assert_equal Topic.pluck(:id).sort, topic_ids
diff --git a/activerecord/test/cases/finder_test.rb b/activerecord/test/cases/finder_test.rb
index 91214da048..73f5312eba 100644
--- a/activerecord/test/cases/finder_test.rb
+++ b/activerecord/test/cases/finder_test.rb
@@ -434,9 +434,9 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_take_and_first_and_last_with_integer_should_use_sql_limit
-    assert_sql(/LIMIT 3|ROWNUM <= 3/) { Topic.take(3).entries }
-    assert_sql(/LIMIT 2|ROWNUM <= 2/) { Topic.first(2).entries }
-    assert_sql(/LIMIT 5|ROWNUM <= 5/) { Topic.last(5).entries }
+    assert_sql(/LIMIT|ROWNUM <=/) { Topic.take(3).entries }
+    assert_sql(/LIMIT|ROWNUM <=/) { Topic.first(2).entries }
+    assert_sql(/LIMIT|ROWNUM <=/) { Topic.last(5).entries }
   end
 
   def test_last_with_integer_and_order_should_keep_the_order