Compat

Signed-off-by: Paul-Elliot <[email protected]>

Author: panglesd

src/loader/compat.cppo.ml

@@ -3,3 +3,14 @@ let get_type_desc = Types.get_desc
 #else
 let get_type_desc t = t.Types.desc
 #endif
+
+(** Extract longident and constructor description from a pattern construct,
+    when it is one. *)
+let get_pattern_construct_info (type a) : a Typedtree.pattern_desc -> _ = function
+#if OCAML_VERSION >= (4,13,0)
+        Typedtree.Tpat_construct (l, { cstr_res; _ }, _, _)
+#else
+        Tpat_construct (l, { cstr_res; _ }, _)
+#endif
+    -> Some (l, cstr_res)
+  | _ -> None

src/loader/occurrences.ml

@@ -57,23 +57,21 @@ module Global_analysis = struct
     | _ -> ()
 
   let pat poses (type a) : a Typedtree.general_pattern -> unit = function
-    | {
-        Typedtree.pat_desc = Tpat_construct (l, { cstr_res; _ }, _, _);
-        pat_loc;
-        _;
-      } -> (
-        let desc = Compat.get_type_desc cstr_res in
-        match desc with
-        | Types.Tconstr (p, _, _) -> (
-            match childpath_of_path p with
-            | None -> ()
-            | Some ref_ ->
-                poses :=
-                  ( ConstructorPath (`Dot (ref_, Longident.last l.txt)),
-                    pos_of_loc pat_loc )
-                  :: !poses)
-        | _ -> ())
-    | _ -> ()
+    | { Typedtree.pat_desc; pat_loc; _ } -> (
+        match Compat.get_pattern_construct_info pat_desc with
+        | Some (l, cstr_res) -> (
+            let desc = Compat.get_type_desc cstr_res in
+            match desc with
+            | Types.Tconstr (p, _, _) -> (
+                match childpath_of_path p with
+                | None -> ()
+                | Some ref_ ->
+                    poses :=
+                      ( ConstructorPath (`Dot (ref_, Longident.last l.txt)),
+                        pos_of_loc pat_loc )
+                      :: !poses)
+            | _ -> ())
+        | None -> ())
 
   let module_expr poses mod_expr =
     match mod_expr with