4 files changed, 76 insertions, 1 deletions
diff --git a/activestorage/test/models/attachments_test.rb b/activestorage/test/models/attachments_test.rb
index 7cfd8683db..ac346c0087 100644
--- a/activestorage/test/models/attachments_test.rb
+++ b/activestorage/test/models/attachments_test.rb
@@ -31,6 +31,31 @@ class ActiveStorage::AttachmentsTest < ActiveSupport::TestCase
     assert_equal "racecar.jpg", @user.avatar.filename.to_s
   end
 
+  test "replace attached blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+
+    perform_enqueued_jobs do
+      assert_no_difference -> { ActiveStorage::Blob.count } do
+        @user.avatar.attach create_blob(filename: "town.jpg")
+      end
+    end
+
+    assert_equal "town.jpg", @user.avatar.filename.to_s
+  end
+
+  test "replace attached blob unsuccessfully" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+
+    perform_enqueued_jobs do
+      assert_raises do
+        @user.avatar.attach nil
+      end
+    end
+
+    assert_equal "funky.jpg", @user.reload.avatar.filename.to_s
+    assert ActiveStorage::Blob.service.exist?(@user.avatar.key)
+  end
+
   test "access underlying associations of new blob" do
     @user.avatar.attach create_blob(filename: "funky.jpg")
     assert_equal @user, @user.avatar_attachment.record
diff --git a/activestorage/test/models/blob_test.rb b/activestorage/test/models/blob_test.rb
index 99f2fb20b0..6e815997ba 100644
--- a/activestorage/test/models/blob_test.rb
+++ b/activestorage/test/models/blob_test.rb
@@ -50,7 +50,7 @@ class ActiveStorage::BlobTest < ActiveSupport::TestCase
 
   private
     def expected_url_for(blob, disposition: :inline)
-      query_string = { content_type: blob.content_type, disposition: disposition }.to_param
+      query_string = { content_type: blob.content_type, disposition: "#{disposition}; #{blob.filename.parameters}" }.to_param
       "/rails/active_storage/disk/#{ActiveStorage.verifier.generate(blob.key, expires_in: 5.minutes, purpose: :blob_key)}/#{blob.filename}?#{query_string}"
     end
 end
diff --git a/activestorage/test/models/filename/parameters_test.rb b/activestorage/test/models/filename/parameters_test.rb
new file mode 100644
index 0000000000..431be00639
--- /dev/null
+++ b/activestorage/test/models/filename/parameters_test.rb
@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require "test_helper"
+
+class ActiveStorage::Filename::ParametersTest < ActiveSupport::TestCase
+  test "parameterizing a Latin filename" do
+    filename = ActiveStorage::Filename.new("racecar.jpg")
+
+    assert_equal %(filename="racecar.jpg"), filename.parameters.ascii
+    assert_equal "filename*=UTF-8''racecar.jpg", filename.parameters.utf8
+    assert_equal "#{filename.parameters.ascii}; #{filename.parameters.utf8}", filename.parameters.combined
+    assert_equal filename.parameters.combined, filename.parameters.to_s
+  end
+
+  test "parameterizing a Latin filename with accented characters" do
+    filename = ActiveStorage::Filename.new("råcëçâr.jpg")
+
+    assert_equal %(filename="racecar.jpg"), filename.parameters.ascii
+    assert_equal "filename*=UTF-8''r%C3%A5c%C3%AB%C3%A7%C3%A2r.jpg", filename.parameters.utf8
+    assert_equal "#{filename.parameters.ascii}; #{filename.parameters.utf8}", filename.parameters.combined
+    assert_equal filename.parameters.combined, filename.parameters.to_s
+  end
+
+  test "parameterizing a non-Latin filename" do
+    filename = ActiveStorage::Filename.new("автомобиль.jpg")
+
+    assert_equal %(filename="%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F.jpg"), filename.parameters.ascii
+    assert_equal "filename*=UTF-8''%D0%B0%D0%B2%D1%82%D0%BE%D0%BC%D0%BE%D0%B1%D0%B8%D0%BB%D1%8C.jpg", filename.parameters.utf8
+    assert_equal "#{filename.parameters.ascii}; #{filename.parameters.utf8}", filename.parameters.combined
+    assert_equal filename.parameters.combined, filename.parameters.to_s
+  end
+end
diff --git a/activestorage/test/models/filename_test.rb b/activestorage/test/models/filename_test.rb
index f1e4a467ba..88405e41c0 100644
--- a/activestorage/test/models/filename_test.rb
+++ b/activestorage/test/models/filename_test.rb
@@ -3,6 +3,24 @@
 require "test_helper"
 
 class ActiveStorage::FilenameTest < ActiveSupport::TestCase
+  test "base" do
+    assert_equal "racecar", ActiveStorage::Filename.new("racecar.jpg").base
+    assert_equal "race.car", ActiveStorage::Filename.new("race.car.jpg").base
+    assert_equal "racecar", ActiveStorage::Filename.new("racecar").base
+  end
+
+  test "extension with delimiter" do
+    assert_equal ".jpg", ActiveStorage::Filename.new("racecar.jpg").extension_with_delimiter
+    assert_equal ".jpg", ActiveStorage::Filename.new("race.car.jpg").extension_with_delimiter
+    assert_equal "", ActiveStorage::Filename.new("racecar").extension_with_delimiter
+  end
+
+  test "extension without delimiter" do
+    assert_equal "jpg", ActiveStorage::Filename.new("racecar.jpg").extension_without_delimiter
+    assert_equal "jpg", ActiveStorage::Filename.new("race.car.jpg").extension_without_delimiter
+    assert_equal "", ActiveStorage::Filename.new("racecar").extension_without_delimiter
+  end
+
   test "sanitize" do
     "%$|:;/\t\r\n\\".each_char do |character|
       filename = ActiveStorage::Filename.new("foo#{character}bar.pdf")