Ensure to calculate column aliases after all table aliases are constructed

Currently, column aliases which is used for eager loading are calculated
before constructing all table aliases in FROM clause.

`JoinDependency#join_constraints` constructs table aliases for `joins`
first, and then always re-constructs table aliases for eager loading.

If both `joins` and eager loading are given a same table association,
the re-construction would cause the discrepancy between column aliases
and table aliases.

To avoid the discrepancy, the column aliases should be calculated after
all table aliases are constructed.

Fixes #30603.

1 files changed, 44 insertions, 2 deletions

diff --git a/activerecord/test/cases/associations/eager_test.rb b/activerecord/test/cases/associations/eager_test.rb
index f46be8734b..8be663e3dc 100644
--- a/activerecord/test/cases/associations/eager_test.rb
+++ b/activerecord/test/cases/associations/eager_test.rb
@@ -77,8 +77,50 @@ class EagerAssociationTest < ActiveRecord::TestCase
   end
 
   def test_loading_with_scope_including_joins
-    assert_equal clubs(:boring_club), Member.preload(:general_club).find(1).general_club
-    assert_equal clubs(:boring_club), Member.eager_load(:general_club).find(1).general_club
+    member = Member.first
+    assert_equal members(:groucho), member
+    assert_equal clubs(:boring_club), member.general_club
+
+    member = Member.preload(:general_club).first
+    assert_equal members(:groucho), member
+    assert_equal clubs(:boring_club), member.general_club
+
+    member = Member.eager_load(:general_club).first
+    assert_equal members(:groucho), member
+    assert_equal clubs(:boring_club), member.general_club
+  end
+
+  def test_loading_association_with_same_table_joins
+    super_memberships = [memberships(:super_membership_of_boring_club)]
+
+    member = Member.joins(:favourite_memberships).first
+    assert_equal members(:groucho), member
+    assert_equal super_memberships, member.super_memberships
+
+    member = Member.joins(:favourite_memberships).preload(:super_memberships).first
+    assert_equal members(:groucho), member
+    assert_equal super_memberships, member.super_memberships
+
+    member = Member.joins(:favourite_memberships).eager_load(:super_memberships).first
+    assert_equal members(:groucho), member
+    assert_equal super_memberships, member.super_memberships
+  end
+
+  def test_loading_association_with_intersection_joins
+    member = Member.joins(:current_membership).first
+    assert_equal members(:groucho), member
+    assert_equal clubs(:boring_club), member.club
+    assert_equal memberships(:membership_of_boring_club), member.current_membership
+
+    member = Member.joins(:current_membership).preload(:club, :current_membership).first
+    assert_equal members(:groucho), member
+    assert_equal clubs(:boring_club), member.club
+    assert_equal memberships(:membership_of_boring_club), member.current_membership
+
+    member = Member.joins(:current_membership).eager_load(:club, :current_membership).first
+    assert_equal members(:groucho), member
+    assert_equal clubs(:boring_club), member.club
+    assert_equal memberships(:membership_of_boring_club), member.current_membership
   end
 
   def test_with_ordering