sizing: accept a bare-number arbitrary aspect ratio

lib/sizing.ml

@@ -246,6 +246,7 @@ module Handler = struct
     | Aspect_video
     | Aspect_ratio of float * float (* aspect-4/3, aspect-8.5/11 *)
     | Aspect_bracket of float * float (* aspect-[10/9] *)
+    | Aspect_bracket_num of string (* aspect-[1.333] single number *)
 
   type Utility.base += Self of t
 
@@ -896,6 +897,7 @@ module Handler = struct
     | Aspect_video -> aspect_video'
     | Aspect_ratio (w, h) -> aspect_ratio' w h
     | Aspect_bracket (w, h) -> aspect_ratio' w h
+    | Aspect_bracket_num s -> aspect_ratio' (float_of_string s) 1.
 
   let err_not_utility = Error (`Msg "Not a sizing utility")
 
@@ -1289,9 +1291,16 @@ module Handler = struct
     | [ "aspect"; "auto" ] -> Ok Aspect_auto
     | [ "aspect"; "square" ] -> Ok Aspect_square
     | [ "aspect"; "video" ] -> Ok Aspect_video
-    | [ "aspect"; value ] when Parse.is_bracket_value value ->
-        parse_aspect_ratio (Parse.bracket_inner value) (fun w h ->
-            Aspect_bracket (w, h))
+    | [ "aspect"; value ] when Parse.is_bracket_value value -> (
+        let inner = Parse.bracket_inner value in
+        match parse_aspect_ratio inner (fun w h -> Aspect_bracket (w, h)) with
+        | Ok _ as ok -> ok
+        | Error _ -> (
+            (* A bare number arbitrary ratio (aspect-[1.333]) is a single-value
+               aspect-ratio, which minifies to just the number. *)
+            match float_of_string_opt inner with
+            | Some f when f > 0. -> Ok (Aspect_bracket_num inner)
+            | _ -> err_not_utility))
     | [ "aspect"; value ] ->
         parse_aspect_ratio value (fun w h -> Aspect_ratio (w, h))
     | _ -> err_not_utility
@@ -1598,6 +1607,8 @@ module Handler = struct
         aspect + int_of_float (rw *. 10.) + int_of_float rh
     | Aspect_bracket (rw, rh) ->
         aspect + 1000 + int_of_float (rw *. 10.) + int_of_float rh
+    | Aspect_bracket_num s ->
+        aspect + 1000 + int_of_float (float_of_string s *. 10.) + 1
     | Aspect_auto -> aspect + 2000
     | Aspect_square -> aspect + 2001
     | Aspect_video -> aspect + 2002
@@ -1847,6 +1858,7 @@ module Handler = struct
           else string_of_float f
         in
         "aspect-[" ^ num w ^ "/" ^ num h ^ "]"
+    | Aspect_bracket_num s -> "aspect-[" ^ s ^ "]"
 end
 
 open Handler

test/test_sizing.ml

@@ -168,6 +168,21 @@ let test_aspect_css () =
   Alcotest.check bool "has 16/9" true
     (Astring.String.is_infix ~affix:"16/9" css)
 
+(* A bare-number arbitrary ratio (aspect-[1.333]) is a single-value
+   aspect-ratio; it minifies to just the number, and round-trips. *)
+let test_aspect_bracket_number () =
+  let css cls =
+    match Tw.of_string cls with
+    | Ok u -> Tw.to_css ~base:false [ u ] |> Tw.Css.to_string ~minify:true
+    | Error (`Msg m) -> Alcotest.failf "%s: %s" cls m
+  in
+  Alcotest.(check bool)
+    "aspect-[1.333] is aspect-ratio:1.333" true
+    (Astring.String.is_infix ~affix:"aspect-ratio:1.333" (css "aspect-[1.333]"));
+  Alcotest.(check string)
+    "aspect-[1.333] round-trips" "aspect-[1.333]"
+    (Tw.pp (Result.get_ok (Tw.of_string "aspect-[1.333]")))
+
 (* aspect-square inlines the 1/1 ratio in v4; it used to emit aspect-ratio:
    var(--aspect-square) with a stray --aspect-square theme token that bare
    Tailwind does not define. *)
@@ -324,6 +339,7 @@ let tests =
     test_case "sizing of_string - invalid values" `Quick of_string_invalid;
     test_case "aspect classes" `Quick test_aspect_classes;
     test_case "aspect css" `Quick test_aspect_css;
+    test_case "aspect bracket number" `Quick test_aspect_bracket_number;
     test_case "aspect-square inlined 1/1" `Quick test_aspect_square_inlined;
     test_case "class generation" `Quick test_class_generation;
     test_case "sizing suborder matches Tailwind" `Quick