add fix (#55)

Signed-off-by: alanechang <[email protected]>

lib/Ast.ml

@@ -2616,11 +2616,14 @@ end = struct
             , Some
                 ( { pexp_desc=
                       ( Pexp_ident _ | Pexp_constant _ | Pexp_record _
-                      | Pexp_field _ )
+                      | Pexp_constraint _ | Pexp_field _ )
                   ; _ } as e0 ) )
           when e0 == exp ->
             false
         | Pexp_record (_, Some e0) when e0 == exp -> true
+        | Pexp_override fields
+          when List.exists fields ~f:(fun (_, e0) -> e0 == exp) ->
+            exposed_right_exp Sequence exp
         | Pexp_sequence (lhs, rhs) -> exp_in_sequence lhs rhs exp
         | Pexp_apply (_, args)
           when List.exists args ~f:(fun (_, e0) ->

lib/Fmt_ast.ml

@@ -2375,11 +2375,12 @@ and fmt_expression c ?(box = true) ?(pro = noop) ?eol ?parens
       pro
       $ hvbox
           (Params.Indent.exp_constraint c.conf)
-          ( wrap_fits_breaks ~space:false c.conf "(" ")"
-              ( fmt_expression c (sub_exp ~ctx e)
-              $ fmt "@ : "
-              $ fmt_core_type c (sub_typ ~ctx t) )
-          $ fmt_atrs )
+          (Params.parens_if parens c.conf
+             ( wrap_fits_breaks ~space:false c.conf "(" ")"
+                 ( fmt_expression c (sub_exp ~ctx e)
+                 $ fmt "@ : "
+                 $ fmt_core_type c (sub_typ ~ctx t) )
+             $ fmt_atrs ) )
   | Pexp_construct ({txt= Lident (("()" | "[]") as txt); loc}, None) ->
       let opn = char txt.[0] and cls = char txt.[1] in
       pro

test/passing/tests/attributes.ml

@@ -444,3 +444,9 @@ let raise_length_mismatch name n1 n2 =
 external unsafe_memset : t -> pos:int -> len:int -> char -> unit
   = "bigstring_memset_stub"
 [@@noalloc]
+
+let _ = f ((1 : int) [@a])
+
+let _ = f ((1 : int) [@a]) ((1 : int) [@a])
+
+let _ = f (((1 : int) [@a] : (int[@b])) [@a]) ((1 : int) [@a])

test/passing/tests/override.ml.ref

@@ -4,6 +4,6 @@ let _ = {<x = (x [@a] : (t[@b])) [@c]>}
 
 let _ = {<x>}
 
-let _ = {<x = (x [@a])>}
+let _ = {<x = x [@a]>}
 
 let _ = {<x>}