From 9698001a0a96455e5692c7aa30201e76bb661828 Mon Sep 17 00:00:00 2001
From: Brian Durand <bbdurand@gmail.com>
Date: Thu, 23 May 2024 21:18:26 -0700
Subject: [PATCH] Added handling for `has_many through` associations to load
 the dependent through associations first.

---
 CHANGELOG.md                    |  1 +
 lib/support_table_data.rb       | 13 +++++++++----
 spec/data/shades.yml            |  5 +++++
 spec/spec_helper.rb             | 20 +++++++++++++++++++-
 spec/support_table_data_spec.rb |  2 +-
 5 files changed, 35 insertions(+), 6 deletions(-)
 create mode 100644 spec/data/shades.yml

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6cb7b54..ef9acc2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Added `named_instance` method to load a named instance from the database.
 - Added class method `named_instance_data` to return attributes from the data files for a named instance.
+- Added handling for `has_many through` associations to load the dependent through associations first.
 
 ## 1.1.2
 
diff --git a/lib/support_table_data.rb b/lib/support_table_data.rb
index 15f60d6..d008335 100644
--- a/lib/support_table_data.rb
+++ b/lib/support_table_data.rb
@@ -398,11 +398,16 @@ def support_table_classes(*extra_classes)
     # @return [Array<Class>]
     def support_table_dependencies(klass)
       dependencies = []
-      klass.reflections.values.select(&:belongs_to?).each do |reflection|
-        if reflection.klass.include?(SupportTableData) && !(reflection.klass <= klass)
-          dependencies << reflection.klass
-        end
+
+      klass.reflections.values.each do |reflection|
+        next if reflection.polymorphic?
+        next unless reflection.klass.include?(SupportTableData)
+        next if reflection.klass <= klass
+        next unless reflection.belongs_to? || reflection.through_reflection?
+
+        dependencies << reflection.klass
       end
+
       dependencies
     end
   end
diff --git a/spec/data/shades.yml b/spec/data/shades.yml
new file mode 100644
index 0000000..9b88241
--- /dev/null
+++ b/spec/data/shades.yml
@@ -0,0 +1,5 @@
+light:
+  name: Light
+
+dark:
+  name: Dark
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index befb4d4..4da7859 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -27,9 +27,14 @@
     t.integer :parent_id
   end
 
+  connection.create_table(:shades) do |t|
+    t.string :name
+  end
+
   connection.create_table(:things) do |t|
     t.string :name
     t.integer :color_id
+    t.integer :shade_id
   end
 
   connection.create_table(:invalids) do |t|
@@ -49,11 +54,13 @@ class Color < ActiveRecord::Base
 
   belongs_to :group
   belongs_to :hue
+  has_many :things
+  has_many :shades, through: :things
 
   validates_uniqueness_of :name
 
   def group_name=(value)
-    self.group = Group.find_by!(name: value)
+    self.group = Group.named_instance(value)
   end
 
   def hue_name=(value)
@@ -97,8 +104,19 @@ def parent_name=(value)
   end
 end
 
+class Shade < ActiveRecord::Base
+  include SupportTableData
+
+  self.support_table_key_attribute = :name
+
+  add_support_table_data "shades.yml"
+
+  validates_uniqueness_of :name
+end
+
 class Thing < ActiveRecord::Base
   belongs_to :color
+  belongs_to :shade
 end
 
 class Invalid < ActiveRecord::Base
diff --git a/spec/support_table_data_spec.rb b/spec/support_table_data_spec.rb
index 7f5b3a3..1510c64 100644
--- a/spec/support_table_data_spec.rb
+++ b/spec/support_table_data_spec.rb
@@ -188,7 +188,7 @@
 
   describe "support_table_classes" do
     it "gets a list of all loaded support table classes with belongs to dependencies listed first" do
-      expect(SupportTableData.support_table_classes).to eq [Group, Hue, Color, Invalid]
+      expect(SupportTableData.support_table_classes).to eq [Group, Hue, Shade, Color, Invalid]
     end
   end