Refactor error evaluation

Summary:
Error evaluation is the defunctionalized version of the callback-hell that was error messages. Unfortunately, it is still very complex with lots of _similar_ types corresponding to different subsets of a `User_error.t`.

This diff takes a first step at reducing the complexity by making subsequent refactors more error resistant by introducing named record types rather than using tuples and eliminating the completely unused `User_error_flags.t` component.

Reviewed By: madgen

Differential Revision: D72396317

fbshipit-source-id: 3d7a1d25f144f74c125142f111a642fa31b7ebcf

Author: Michael Thomas

hphp/hack/src/client/clientLsp.ml

@@ -1164,7 +1164,6 @@ let ide_diagnostics_to_lsp_diagnostics
       explanation = _;
       custom_msgs;
       is_fixmed = _;
-      flags = _;
       quickfixes = _;
       function_pos = _;
     } =

hphp/hack/src/errors/contextual_error_formatter.ml

@@ -213,7 +213,6 @@ let to_string
     explanation = _;
     custom_msgs;
     quickfixes = _;
-    flags = _;
     is_fixmed = _;
     function_pos = _;
   } =

hphp/hack/src/errors/dune

@@ -52,8 +52,7 @@
     render
     message
     quickfix
-    user_error
-    user_error_flags)
+    user_error)
   (libraries
     core_kernel
     classish_positions

hphp/hack/src/errors/errors.ml

@@ -195,7 +195,6 @@ let try_with_result (f1 : unit -> 'res) (f2 : 'res -> error -> 'res) : 'res =
           explanation;
           quickfixes;
           custom_msgs;
-          flags;
           function_pos;
           is_fixmed = _;
         } ->
@@ -220,7 +219,6 @@ let try_with_result (f1 : unit -> 'res) (f2 : 'res -> error -> 'res) : 'res =
          explanation
          ~quickfixes
          ~custom_msgs
-         ~flags
          ?function_pos
 
 let try_with_result_pure ~fail f g =
@@ -324,7 +322,6 @@ let compare_internal (x : ('a, 'b) User_error.t) (y : ('a, 'b) User_error.t) :
           custom_msgs = _;
           quickfixes = _;
           is_fixmed = _;
-          flags = _;
           function_pos = _;
         } =
     x
@@ -339,7 +336,6 @@ let compare_internal (x : ('a, 'b) User_error.t) (y : ('a, 'b) User_error.t) :
           custom_msgs = _;
           quickfixes = _;
           is_fixmed = _;
-          flags = _;
           function_pos = _;
         } =
     y
@@ -705,7 +701,6 @@ let add_error_with_fixme_error error explanation ~fixme_pos =
           explanation = _;
           quickfixes;
           custom_msgs;
-          flags;
           function_pos;
           is_fixmed = _;
         } =
@@ -721,7 +716,6 @@ let add_error_with_fixme_error error explanation ~fixme_pos =
        Explanation.empty
        ~quickfixes
        ~custom_msgs
-       ~flags
        ?function_pos
 
 let add_applied_fixme error =
@@ -836,7 +830,6 @@ let add_error (error : error) =
           explanation;
           quickfixes;
           custom_msgs;
-          flags;
           function_pos;
           is_fixmed = _;
         } =
@@ -852,7 +845,6 @@ let add_error (error : error) =
       explanation
       ~quickfixes
       ~custom_msgs
-      ~flags
       ?function_pos
   in
 
@@ -1352,7 +1344,6 @@ let convert_errors_to_string ?(include_filename = false) (errors : error list) :
               explanation = _;
               quickfixes = _;
               is_fixmed = _;
-              flags = _;
               function_pos = _;
             } =
         err

hphp/hack/src/errors/fmt_plain.rs

@@ -26,7 +26,6 @@ impl<'a> std::fmt::Display for FmtPlain<'a> {
                 custom_msgs,
                 quickfixes: _,
                 is_fixmed: _,
-                flags: _,
                 function_pos: _,
             },
             ctx,

hphp/hack/src/errors/fmt_raw.rs

@@ -30,7 +30,6 @@ impl<'a> std::fmt::Display for FmtRaw<'a> {
                 custom_msgs,
                 quickfixes: _,
                 is_fixmed: _,
-                flags: _,
                 function_pos: _,
             },
             ctx,

hphp/hack/src/errors/highlighted_error_formatter.ml

@@ -571,7 +571,6 @@ let to_string (error : Errors.finalized_error) : string =
     custom_msgs;
     explanation = _;
     quickfixes = _;
-    flags = _;
     is_fixmed = _;
     function_pos = _;
   } =

hphp/hack/src/errors/raw_error_formatter.ml

@@ -56,7 +56,6 @@ let to_string (error : Errors.finalized_error) : string =
     quickfixes = _;
     custom_msgs = _;
     is_fixmed = _;
-    flags = _;
     function_pos = _;
   } =
     error

hphp/hack/src/errors/user_error.ml

@@ -38,7 +38,6 @@ type ('prim_pos, 'pos) t = {
   quickfixes: 'prim_pos Quickfix.t list; [@hash.ignore]
   custom_msgs: string list;
   is_fixmed: bool;
-  flags: User_error_flags.t;
   function_pos: 'prim_pos option;
 }
 [@@deriving eq, hash, ord, show]
@@ -52,7 +51,6 @@ let make
     ?(is_fixmed = false)
     ?(quickfixes = [])
     ?(custom_msgs = [])
-    ?(flags = User_error_flags.empty)
     ?function_pos
     claim
     reasons
@@ -66,7 +64,6 @@ let make
     quickfixes;
     custom_msgs;
     is_fixmed;
-    flags;
     function_pos;
   }
 
@@ -75,7 +72,6 @@ let make_err
     ?is_fixmed
     ?quickfixes
     ?custom_msgs
-    ?flags
     ?function_pos
     claim
     reasons
@@ -86,20 +82,18 @@ let make_err
     ?is_fixmed
     ?quickfixes
     ?custom_msgs
-    ?flags
     ?function_pos
     claim
     reasons
     explanation
 
-let make_warning code ?is_fixmed ?quickfixes ?custom_msgs ?flags claim reasons =
+let make_warning code ?is_fixmed ?quickfixes ?custom_msgs claim reasons =
   make
     Warning
     code
     ?is_fixmed
     ?quickfixes
     ?custom_msgs
-    ?flags
     claim
     reasons
     Explanation.empty
@@ -127,7 +121,6 @@ let to_absolute
       quickfixes;
       custom_msgs;
       is_fixmed;
-      flags;
       function_pos;
     } =
   let pos_or_decl_to_absolute_pos pos_or_decl =
@@ -153,7 +146,6 @@ let to_absolute
     quickfixes;
     custom_msgs;
     is_fixmed;
-    flags;
     function_pos;
   }
 
@@ -179,7 +171,6 @@ let make_absolute severity code = function
       quickfixes = [];
       custom_msgs = [];
       is_fixmed = false;
-      flags = User_error_flags.empty;
       function_pos = None;
     }
 
@@ -193,7 +184,6 @@ let to_absolute_for_test
       quickfixes;
       custom_msgs;
       is_fixmed;
-      flags;
       function_pos;
     } =
   let f (p, s) =
@@ -228,7 +218,6 @@ let to_absolute_for_test
     quickfixes;
     custom_msgs;
     is_fixmed;
-    flags;
     function_pos;
   }
 
@@ -290,7 +279,7 @@ let to_string { severity; code; claim; reasons; custom_msgs; _ } =
 
 let to_json ~(human_formatter : (_ -> string) option) ~filename_to_string error
     =
-  let { severity; code; claim; reasons; flags; custom_msgs; function_pos; _ } =
+  let { severity; code; claim; reasons; custom_msgs; function_pos; _ } =
     error
   in
   let msgl = claim :: reasons in
@@ -310,13 +299,11 @@ let to_json ~(human_formatter : (_ -> string) option) ~filename_to_string error
   let custom_msgs =
     List.map ~f:(fun msg -> Hh_json.JSON_String msg) custom_msgs
   in
-  let flags = User_error_flags.to_json flags in
   let human_format = Option.map ~f:(fun f -> f error) human_formatter in
   let obj =
     ("severity", Hh_json.JSON_String (Severity.to_string severity))
     :: ("message", Hh_json.JSON_Array elts)
     :: ("custom_messages", Hh_json.JSON_Array custom_msgs)
-    :: ("flags", flags)
     :: List.filter_opt
          [
            Option.map human_format ~f:(fun human_format ->

hphp/hack/src/errors/user_error.mli

@@ -28,7 +28,6 @@ type ('prim_pos, 'pos) t = {
   quickfixes: 'prim_pos Quickfix.t list; [@hash.ignore]
   custom_msgs: string list;
   is_fixmed: bool;
-  flags: User_error_flags.t;
   function_pos: 'prim_pos option;
 }
 [@@deriving eq, hash, ord, show]
@@ -41,7 +40,6 @@ val make :
   ?is_fixmed:bool ->
   ?quickfixes:'a Quickfix.t list ->
   ?custom_msgs:string list ->
-  ?flags:User_error_flags.t ->
   ?function_pos:'a ->
   'a Message.t ->
   'b Message.t list ->
@@ -54,7 +52,6 @@ val make_err :
   ?is_fixmed:bool ->
   ?quickfixes:'a Quickfix.t list ->
   ?custom_msgs:string list ->
-  ?flags:User_error_flags.t ->
   ?function_pos:'a ->
   'a Message.t ->
   'b Message.t list ->
@@ -67,7 +64,6 @@ val make_warning :
   ?is_fixmed:bool ->
   ?quickfixes:'a Quickfix.t list ->
   ?custom_msgs:string list ->
-  ?flags:User_error_flags.t ->
   'a Message.t ->
   'b Message.t list ->
   ('a, 'b) t