1 files changed, 42 insertions, 0 deletions
diff --git a/activerecord/test/cases/relations_test.rb b/activerecord/test/cases/relations_test.rb
index adc50a694e..b27815539b 100644
--- a/activerecord/test/cases/relations_test.rb
+++ b/activerecord/test/cases/relations_test.rb
@@ -182,6 +182,48 @@ class RelationTest < ActiveRecord::TestCase
     end
   end
 
+  def test_select_with_original_table_name_in_from
+    relation = Comment.joins(:post).select(:id).order(:id)
+    subquery = Comment.from(Comment.table_name).joins(:post).select(:id).order(:id)
+    assert_equal relation.map(&:id), subquery.map(&:id)
+  end
+
+  def test_pluck_with_original_table_name_in_from
+    relation = Comment.joins(:post).order(:id)
+    subquery = Comment.from(Comment.table_name).joins(:post).order(:id)
+    assert_equal relation.pluck(:id), subquery.pluck(:id)
+  end
+
+  def test_select_with_quoted_original_table_name_in_from
+    relation = Comment.joins(:post).select(:id).order(:id)
+    subquery = Comment.from(Comment.quoted_table_name).joins(:post).select(:id).order(:id)
+    assert_equal relation.map(&:id), subquery.map(&:id)
+  end
+
+  def test_pluck_with_quoted_original_table_name_in_from
+    relation = Comment.joins(:post).order(:id)
+    subquery = Comment.from(Comment.quoted_table_name).joins(:post).order(:id)
+    assert_equal relation.pluck(:id), subquery.pluck(:id)
+  end
+
+  def test_select_with_subquery_in_from_uses_original_table_name
+    if current_adapter?(:SQLite3Adapter) && (ENV["TRAVIS"] || ENV["BUILDKITE"])
+      skip <<~MSG
+        https://travis-ci.org/rails/rails/jobs/496726410#L1198-L1208
+        https://buildkite.com/rails/rails/builds/58981#2423c707-7c56-4639-a76e-8db4fd1e5cf3/102-111
+      MSG
+    end
+    relation = Comment.joins(:post).select(:id).order(:id)
+    subquery = Comment.from(Comment.all, Comment.quoted_table_name).joins(:post).select(:id).order(:id)
+    assert_equal relation.map(&:id), subquery.map(&:id)
+  end
+
+  def test_pluck_with_subquery_in_from_uses_original_table_name
+    relation = Comment.joins(:post).order(:id)
+    subquery = Comment.from(Comment.all, Comment.quoted_table_name).joins(:post).order(:id)
+    assert_equal relation.pluck(:id), subquery.pluck(:id)
+  end
+
   def test_select_with_subquery_in_from_does_not_use_original_table_name
     relation = Comment.group(:type).select("COUNT(post_id) AS post_count, type")
     subquery = Comment.from(relation).select("type", "post_count")