Recommend using :resize_to_fit after all

actionview/lib/action_view/helpers/asset_tag_helper.rb

@@ -325,9 +325,9 @@ def preload_link_tag(source, options = {})
       #
       #   image_tag(user.avatar)
       #   # => <img src="/rails/active_storage/blobs/.../tiger.jpg" />
-      #   image_tag(user.avatar.variant(resize: "100x100"))
+      #   image_tag(user.avatar.variant(resize_to_fit: [100, 100]))
       #   # => <img src="/rails/active_storage/variants/.../tiger.jpg" />
-      #   image_tag(user.avatar.variant(resize: "100x100"), size: '100')
+      #   image_tag(user.avatar.variant(resize_to_fit: [100, 100]), size: '100')
       #   # => <img width="100" height="100" src="/rails/active_storage/variants/.../tiger.jpg" />
       def image_tag(source, options = {})
         options = options.symbolize_keys

activestorage/README.md

@@ -99,7 +99,7 @@ Variation of image attachment:
 
 ```erb
 <%# Hitting the variant URL will lazy transform the original blob and then redirect to its new service location %>
-<%= image_tag user.avatar.variant(resize: "100x100") %>
+<%= image_tag user.avatar.variant(resize_to_fit: [100, 100]) %>
 ```
 
 ## Direct uploads

activestorage/app/models/active_storage/blob/representable.rb

@@ -10,7 +10,7 @@ module ActiveStorage::Blob::Representable
   # Returns an ActiveStorage::Variant instance with the set of +transformations+ provided. This is only relevant for image
   # files, and it allows any image to be transformed for size, colors, and the like. Example:
   #
-  #   avatar.variant(resize: "100x100").processed.service_url
+  #   avatar.variant(resize_to_fit: [100, 100]).processed.service_url
   #
   # This will create and process a variant of the avatar blob that's constrained to a height and width of 100px.
   # Then it'll upload said variant to the service according to a derivative key of the blob and the transformations.
@@ -18,7 +18,7 @@ module ActiveStorage::Blob::Representable
   # Frequently, though, you don't actually want to transform the variant right away. But rather simply refer to a
   # specific variant that can be created by a controller on-demand. Like so:
   #
-  #   <%= image_tag Current.user.avatar.variant(resize: "100x100") %>
+  #   <%= image_tag Current.user.avatar.variant(resize_to_fit: [100, 100]) %>
   #
   # This will create a URL for that specific blob with that specific variant, which the ActiveStorage::RepresentationsController
   # can then produce on-demand.
@@ -43,13 +43,13 @@ def variable?
   # from a non-image blob. Active Storage comes with built-in previewers for videos and PDF documents. The video previewer
   # extracts the first frame from a video and the PDF previewer extracts the first page from a PDF document.
   #
-  #   blob.preview(resize: "100x100").processed.service_url
+  #   blob.preview(resize_to_fit: [100, 100]).processed.service_url
   #
   # Avoid processing previews synchronously in views. Instead, link to a controller action that processes them on demand.
   # Active Storage provides one, but you may want to create your own (for example, if you need authentication). Here’s
   # how to use the built-in version:
   #
-  #   <%= image_tag video.preview(resize: "100x100") %>
+  #   <%= image_tag video.preview(resize_to_fit: [100, 100]) %>
   #
   # This method raises ActiveStorage::UnpreviewableError if no previewer accepts the receiving blob. To determine
   # whether a blob is accepted by any previewer, call ActiveStorage::Blob#previewable?.
@@ -69,7 +69,7 @@ def previewable?
 
   # Returns an ActiveStorage::Preview for a previewable blob or an ActiveStorage::Variant for a variable image blob.
   #
-  #   blob.representation(resize: "100x100").processed.service_url
+  #   blob.representation(resize_to_fit: [100, 100]).processed.service_url
   #
   # Raises ActiveStorage::UnrepresentableError if the receiving blob is neither variable nor previewable. Call
   # ActiveStorage::Blob#representable? to determine whether a blob is representable.

activestorage/app/models/active_storage/preview.rb

@@ -38,7 +38,7 @@ def initialize(blob, variation_or_variation_key)
 
   # Processes the preview if it has not been processed yet. Returns the receiving Preview instance for convenience:
   #
-  #   blob.preview(resize: "100x100").processed.service_url
+  #   blob.preview(resize_to_fit: [100, 100]).processed.service_url
   #
   # Processing a preview generates an image from its blob and attaches the preview image to the blob. Because the preview
   # image is stored with the blob, it is only generated once.

activestorage/app/models/active_storage/variant.rb

@@ -27,7 +27,7 @@
 # To refer to such a delayed on-demand variant, simply link to the variant through the resolved route provided
 # by Active Storage like so:
 #
-#   <%= image_tag Current.user.avatar.variant(resize: "100x100") %>
+#   <%= image_tag Current.user.avatar.variant(resize_to_fit: [100, 100]) %>
 #
 # This will create a URL for that specific blob with that specific variant, which the ActiveStorage::RepresentationsController
 # can then produce on-demand.
@@ -36,15 +36,15 @@
 # has already been processed and uploaded to the service, and, if so, just return that. Otherwise it will perform
 # the transformations, upload the variant to the service, and return itself again. Example:
 #
-#   avatar.variant(resize: "100x100").processed.service_url
+#   avatar.variant(resize_to_fit: [100, 100]).processed.service_url
 #
 # This will create and process a variant of the avatar blob that's constrained to a height and width of 100.
 # Then it'll upload said variant to the service according to a derivative key of the blob and the transformations.
 #
-# You can combine any number of ImageMagick/libvips operations into a variant. In addition to that, you can also use
-# any macros provided by the ImageProcessing gem (such as +resize_to_limit+).
+# You can combine any number of ImageMagick/libvips operations into a variant, as well as any macros provided by the
+# ImageProcessing gem (such as +resize_to_fit+):
 #
-#   avatar.variant(resize_to_limit: [800, 800], monochrome: true, flip: "-90")
+#   avatar.variant(resize_to_fit: [800, 800], monochrome: true, flip: "-90")
 #
 # Visit the following links for a list of available ImageProcessing commands and ImageMagick/libvips operations:
 #

activestorage/app/models/active_storage/variation.rb

@@ -6,7 +6,7 @@
 # In case you do need to use this directly, it's instantiated using a hash of transformations where
 # the key is the command and the value is the arguments. Example:
 #
-#   ActiveStorage::Variation.new(resize: "100x100", monochrome: true, trim: true, rotate: "-90")
+#   ActiveStorage::Variation.new(resize_to_fit: [100, 100], monochrome: true, trim: true, rotate: "-90")
 #
 # The options map directly to {ImageProcessing}[https://github.com/janko-m/image_processing] commands.
 class ActiveStorage::Variation

guides/source/active_storage_overview.md

@@ -353,7 +353,7 @@ original blob into the format you specified and redirect to its new service
 location.
 
 ```erb
-<%= image_tag user.avatar.variant(resize: "100x100") %>
+<%= image_tag user.avatar.variant(resize_to_fit: [100, 100]) %>
 ```
 
 To switch to the Vips processor, you would add the following to
@@ -375,7 +375,7 @@ the box, Active Storage supports previewing videos and PDF documents.
 <ul>
   <% @message.files.each do |file| %>
     <li>
-      <%= image_tag file.preview(resize: "100x100>") %>
+      <%= image_tag file.preview(resize_to_limit: [100, 100]) %>
     </li>
   <% end %>
 </ul>