Fix blob associations

cc @javan

3 files changed, 21 insertions, 2 deletions

diff --git a/lib/active_storage/attached/macros.rb b/lib/active_storage/attached/macros.rb
index 54c2731c08..11f88f16e5 100644
--- a/lib/active_storage/attached/macros.rb
+++ b/lib/active_storage/attached/macros.rb
@@ -18,7 +18,7 @@ module ActiveStorage::Attached::Macros
     end
 
     has_one :"#{name}_attachment", -> { where(name: name) }, class_name: "ActiveStorage::Attachment", as: :record
-    has_one :"#{name}_blob", through: :"#{name}_attachment"
+    has_one :"#{name}_blob", through: :"#{name}_attachment", class_name: "ActiveStorage::Blob", source: :blob
 
     if dependent == :purge_later
       before_destroy { public_send(name).purge_later }
@@ -47,7 +47,7 @@ module ActiveStorage::Attached::Macros
     end
 
     has_many :"#{name}_attachments", -> { where(name: name) }, as: :record, class_name: "ActiveStorage::Attachment"
-    has_many :"#{name}_blobs", through: :"#{name}_attachments"
+    has_many :"#{name}_blobs", through: :"#{name}_attachments", class_name: "ActiveStorage::Blob", source: :blob
 
     scope :"with_attached_#{name}", -> { includes("#{name}_attachments": :blob) }
 
diff --git a/test/models/attachments_test.rb b/test/models/attachments_test.rb
index eac3cbe680..82256e1f44 100644
--- a/test/models/attachments_test.rb
+++ b/test/models/attachments_test.rb
@@ -30,6 +30,13 @@ class ActiveStorage::AttachmentsTest < ActiveSupport::TestCase
     assert_equal "town.jpg", @user.avatar.filename.to_s
   end
 
+  test "access underlying associations of new blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    assert_equal @user, @user.avatar_attachment.record
+    assert_equal @user.avatar_attachment.blob, @user.avatar_blob
+    assert_equal "funky.jpg", @user.avatar_attachment.blob.filename.to_s
+  end
+
   test "purge attached blob" do
     @user.avatar.attach create_blob(filename: "funky.jpg")
     avatar_key = @user.avatar.key
@@ -79,6 +86,17 @@ class ActiveStorage::AttachmentsTest < ActiveSupport::TestCase
     assert_equal "country.jpg", highlights.second.filename.to_s
   end
 
+  test "access underlying associations of new blobs" do
+    @user.highlights.attach(
+      { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" },
+      { io: StringIO.new("IT"), filename: "country.jpg", content_type: "image/jpg" })
+
+    assert_equal @user, @user.highlights_attachments.first.record
+    assert_equal @user.highlights_attachments.collect(&:blob).sort, @user.highlights_blobs.sort
+    assert_equal "town.jpg", @user.highlights_attachments.first.blob.filename.to_s
+  end
+
+
   test "purge attached blobs" do
     @user.highlights.attach create_blob(filename: "funky.jpg"), create_blob(filename: "wonky.jpg")
     highlight_keys = @user.highlights.collect(&:key)
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 650e997205..d3a55e2cf0 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -23,6 +23,7 @@ rescue Errno::ENOENT
   {}
 end
 
+require "active_storage/blob"
 require "active_storage/service/disk_service"
 require "tmpdir"
 ActiveStorage::Blob.service = ActiveStorage::Service::DiskService.new(root: Dir.mktmpdir("active_storage_tests"))