2 files changed, 41 insertions, 3 deletions
diff --git a/activestorage/test/models/preview_test.rb b/activestorage/test/models/preview_test.rb
new file mode 100644
index 0000000000..317a2d5c58
--- /dev/null
+++ b/activestorage/test/models/preview_test.rb
@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::PreviewTest < ActiveSupport::TestCase
+  test "previewing a PDF" do
+    blob = create_file_blob(filename: "report.pdf", content_type: "application/pdf")
+    preview = blob.preview(resize: "640x280").processed
+    assert preview.image.attached?
+    assert_equal "report.png", preview.image.filename.to_s
+    assert_equal "image/png", preview.image.content_type
+
+    image = read_image(preview.image)
+    assert_equal 612, image.width
+    assert_equal 792, image.height
+  end
+
+  test "previewing an MP4 video" do
+    blob = create_file_blob(filename: "video.mp4", content_type: "video/mp4")
+    preview = blob.preview(resize: "640x280").processed
+    assert preview.image.attached?
+    assert_equal "video.png", preview.image.filename.to_s
+    assert_equal "image/png", preview.image.content_type
+
+    image = read_image(preview.image)
+    assert_equal 640, image.width
+    assert_equal 480, image.height
+  end
+
+  test "previewing an unpreviewable blob" do
+    blob = create_file_blob
+
+    assert_raises ActiveStorage::Blob::UnpreviewableError do
+      blob.preview resize: "640x280"
+    end
+  end
+end
diff --git a/activestorage/test/models/variant_test.rb b/activestorage/test/models/variant_test.rb
index ca112ab907..d7cbef4e55 100644
--- a/activestorage/test/models/variant_test.rb
+++ b/activestorage/test/models/variant_test.rb
@@ -5,14 +5,14 @@ require "database/setup"
 
 class ActiveStorage::VariantTest < ActiveSupport::TestCase
   setup do
-    @blob = create_image_blob filename: "racecar.jpg"
+    @blob = create_file_blob filename: "racecar.jpg"
   end
 
   test "resized variation" do
     variant = @blob.variant(resize: "100x100").processed
     assert_match(/racecar\.jpg/, variant.service_url)
 
-    image = read_image_variant(variant)
+    image = read_image(variant)
     assert_equal 100, image.width
     assert_equal 67, image.height
   end
@@ -21,7 +21,7 @@ class ActiveStorage::VariantTest < ActiveSupport::TestCase
     variant = @blob.variant(resize: "100x100", monochrome: true).processed
     assert_match(/racecar\.jpg/, variant.service_url)
 
-    image = read_image_variant(variant)
+    image = read_image(variant)
     assert_equal 100, image.width
     assert_equal 67, image.height
     assert_match(/Gray/, image.colorspace)