Raise ArgumentError when a instance of ActiveRecord::Base is passed to

find and exists?

activerecord/CHANGELOG.md

@@ -1,3 +1,8 @@
+*   Raise `ArgumentError` when passing an `ActiveRecord::Base` instance to `.find`
+    and `.exists?`.
+
+    *Rafael Mendonça França*
+
 *   Respect precision option for arrays of timestamps.
 
     Fixes #27514.

activerecord/lib/active_record/core.rb

@@ -171,23 +171,19 @@ module ActiveRecord
         return super if block_given? ||
                         primary_key.nil? ||
                         scope_attributes? ||
-                        columns_hash.include?(inheritance_column) ||
-                        ids.first.kind_of?(Array)
+                        columns_hash.include?(inheritance_column)
 
         id = ids.first
-        if ActiveRecord::Base === id
-          id = id.id
-          ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            You are passing an instance of ActiveRecord::Base to `find`.
-            Please pass the id of the object by calling `.id`.
-          MSG
-        end
+
+        return super if id.kind_of?(Array) ||
+                         id.is_a?(ActiveRecord::Base)
 
         key = primary_key
 
         statement = cached_find_by_statement(key) { |params|
           where(key => params.bind).limit(1)
         }
+
         record = statement.execute([id], self, connection).first
         unless record
           raise RecordNotFound.new("Couldn't find #{name} with '#{primary_key}'=#{id}",

activerecord/lib/active_record/relation/finder_methods.rb

@@ -301,8 +301,7 @@ module ActiveRecord
     #   Person.exists?
     def exists?(conditions = :none)
       if Base === conditions
-        conditions = conditions.id
-        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+        raise ArgumentError, <<-MSG.squish
           You are passing an instance of ActiveRecord::Base to `exists?`.
           Please pass the id of the object by calling `.id`.
         MSG
@@ -456,11 +455,10 @@ module ActiveRecord
 
         def find_one(id)
           if ActiveRecord::Base === id
-            id = id.id
-            ActiveSupport::Deprecation.warn(<<-MSG.squish)
-            You are passing an instance of ActiveRecord::Base to `find`.
-            Please pass the id of the object by calling `.id`.
-          MSG
+            raise ArgumentError, <<-MSG.squish
+              You are passing an instance of ActiveRecord::Base to `find`.
+              Please pass the id of the object by calling `.id`.
+            MSG
           end
 
           relation = where(primary_key => id)

activerecord/test/cases/finder_test.rb

@@ -118,7 +118,7 @@ class FinderTest < ActiveRecord::TestCase
   end
 
   def test_find_passing_active_record_object_is_deprecated
-    assert_deprecated do
+    assert_raises(ArgumentError) do
       Topic.find(Topic.last)
     end
   end
@@ -167,8 +167,8 @@ class FinderTest < ActiveRecord::TestCase
     assert_equal false, relation.exists?(false)
   end
 
-  def test_exists_passing_active_record_object_is_deprecated
-    assert_deprecated do
+  def test_exists_passing_active_record_object_is_not_permited
+    assert_raises(ArgumentError) do
       Topic.exists?(Topic.new)
     end
   end