重现的步骤

class Product < ApplicationRecord
   has_many_attached :images
end

在视图中:

<%= image_tag(url_for(@product.images.first.variant(resize: "100x100", flip: "-90"))) %>

预期的行为

应该翻转图像

实际行为

图像未加载,

image

在我有的日志中

MiniMagick::Error (`mogrify -flip -90 /tmp/mini_magick20180808-26054-yjj6f4.jpg` failed with error:
mogrify-im6.q16: unable to open image `-90': No such file or directory @ error/blob.c/OpenBlob/2701.
mogrify-im6.q16: no decode delegate for this image format `' @ error/constitute.c/ReadImage/504.
):

而以下选项工作正常

<%= image_tag(url_for(@product.images.first.variant(resize: "100x100"))) %>
<%= image_tag(url_for(@product.images.first.variant(resize: "100x100", rotate: "-180"))) %>
<%= image_tag(url_for(@product.images.first.variant(resize: "100x100", rotate: "-180", monochrome: true))) %>

系统配置

Rails version :5.2

Ruby version :2.3.3