Don't write original file if it wasn't reprocessed

If `only_process` list is not empty, but it doesn't contain `:original`
style, original file hasn't been reprocessed and it's not needed to
rewrite/reupload it.

[fixes #1993]
[fixes #2046]
[fixes #1804]

lib/paperclip/attachment.rb

@@ -50,7 +50,7 @@ module Paperclip
     # +url+ - a relative URL of the attachment. This is interpolated using +interpolator+
     # +url+ - a relative URL of the attachment. This is interpolated using +interpolator+
     # +path+ - where on the filesystem to store the attachment. This is interpolated using +interpolator+
     # +path+ - where on the filesystem to store the attachment. This is interpolated using +interpolator+
     # +styles+ - a hash of options for processing the attachment. See +has_attached_file+ for the details
     # +styles+ - a hash of options for processing the attachment. See +has_attached_file+ for the details
-    # +only_process+ - style args to be run through the post-processor. This defaults to the empty list (which is 
+    # +only_process+ - style args to be run through the post-processor. This defaults to the empty list (which is
     #                  a special case that indicates all styles should be processed)
     #                  a special case that indicates all styles should be processed)
     # +default_url+ - a URL for the missing image
     # +default_url+ - a URL for the missing image
     # +default_style+ - the style to use when an argument is not specified e.g. #url, #path
     # +default_style+ - the style to use when an argument is not specified e.g. #url, #path
@@ -238,6 +238,9 @@ module Paperclip
     # the instance's errors and returns false, cancelling the save.
     # the instance's errors and returns false, cancelling the save.
     def save
     def save
       flush_deletes unless @options[:keep_old_files]
       flush_deletes unless @options[:keep_old_files]
+      if @options[:only_process].any? && !@options[:only_process].include?(:original)
+        @queued_for_write.except!(:original)
+      end
       flush_writes
       flush_writes
       @dirty = false
       @dirty = false
       true
       true

spec/paperclip/storage/s3_spec.rb

@@ -364,6 +364,58 @@ describe Paperclip::Storage::S3 do
     end
     end
   end
   end
 
 
+  context "An attachment that uses S3 for storage and has styles" do
+    before do
+      rebuild_model(
+        (aws2_add_region).merge(
+          storage: :s3,
+          styles: { thumb: ["90x90#", :jpg] },
+          bucket: "bucket",
+          s3_credentials: {
+            "access_key_id" => "12345",
+            "secret_access_key" => "54321" }
+        )
+      )
+
+      @file = File.new(fixture_file("5k.png"), "rb")
+      @dummy = Dummy.new
+      @dummy.avatar = @file
+      @dummy.save
+    end
+
+    context "reprocess" do
+      before do
+        @object = stub
+        @dummy.avatar.stubs(:s3_object).with(:original).returns(@object)
+        @dummy.avatar.stubs(:s3_object).with(:thumb).returns(@object)
+        @object.stubs(:get).yields(@file.read)
+        @object.stubs(:exists?).returns(true)
+      end
+
+      it "uploads original" do
+        @object.expects(:upload_file).with(
+          anything,
+          content_type: "image/png",
+          acl: :"public-read").returns(true)
+        @object.expects(:upload_file).with(
+          anything,
+          content_type: "image/jpeg",
+          acl: :"public-read").returns(true)
+        @dummy.avatar.reprocess!
+      end
+
+      it "doesn't upload original" do
+        @object.expects(:upload_file).with(
+          anything,
+          content_type: "image/jpeg",
+          acl: :"public-read").returns(true)
+        @dummy.avatar.reprocess!(:thumb)
+      end
+    end
+
+    after { @file.close }
+  end
+
   context "An attachment that uses S3 for storage and has spaces in file name" do
   context "An attachment that uses S3 for storage and has spaces in file name" do
     before do
     before do
       rebuild_model(
       rebuild_model(