Translate service-specific missing object exceptions into a generic one

`ActiveStorage::Blob#download` and `ActiveStorage::Blob#open` raise
`ActiveStorage::FileNotFoundError` when the corresponding file is missing
from the storage service. Services translate service-specific missing
object exceptions (e.g. `Google::Cloud::NotFoundError` for the GCS service
and `Errno::ENOENT` for the disk service) into
`ActiveStorage::FileNotFoundError`.

1 files changed, 21 insertions, 0 deletions

diff --git a/activestorage/test/service/shared_service_tests.rb b/activestorage/test/service/shared_service_tests.rb
index 30cfca4e36..58f189af2b 100644
--- a/activestorage/test/service/shared_service_tests.rb
+++ b/activestorage/test/service/shared_service_tests.rb
@@ -50,6 +50,13 @@ module ActiveStorage::Service::SharedServiceTests
       assert_equal FIXTURE_DATA, @service.download(@key)
     end
 
+    test "downloading a nonexistent file" do
+      assert_raises(ActiveStorage::FileNotFoundError) do
+        @service.download(SecureRandom.base58(24))
+      end
+    end
+
+
     test "downloading in chunks" do
       key = SecureRandom.base58(24)
       expected_chunks = [ "a" * 5.megabytes, "b" ]
@@ -68,11 +75,25 @@ module ActiveStorage::Service::SharedServiceTests
       end
     end
 
+    test "downloading a nonexistent file in chunks" do
+      assert_raises(ActiveStorage::FileNotFoundError) do
+        @service.download(SecureRandom.base58(24)) {}
+      end
+    end
+
+
     test "downloading partially" do
       assert_equal "\x10\x00\x00", @service.download_chunk(@key, 19..21)
       assert_equal "\x10\x00\x00", @service.download_chunk(@key, 19...22)
     end
 
+    test "partially downloading a nonexistent file" do
+      assert_raises(ActiveStorage::FileNotFoundError) do
+        @service.download_chunk(SecureRandom.base58(24), 19..21)
+      end
+    end
+
+
     test "existing" do
       assert @service.exist?(@key)
       assert_not @service.exist?(@key + "nonsense")