Revert "Compatibility with OCaml 5.1 (#1150)"

This reverts commit c28f560.

Author: voodoos

.github/workflows/build-and-test.yml

@@ -61,9 +61,7 @@ jobs:
       - name: Build and install dependencies
         run: opam install .
 
-      # the makefile explains why we don't use --with-test
-      # ppx expect is not yet compatible with 5.1 and test output vary from one
-      # compiler to another. We only test on 4.14.
+      # the makefile explains why we don't use test dependencies
       - name: Install test dependencies
         if: matrix.ocaml-compiler == '4.14'
         run: opam exec -- make install-test-deps

ocaml-lsp-server/src/folding_range.ml

@@ -67,9 +67,10 @@ let fold_over_parsetree (parsetree : Mreader.parsetree) =
         let range = Range.of_loc module_expr.pmod_loc in
         push range;
         Ast_iterator.default_iterator.module_expr self module_expr
-      | _ ->
-        (* We rely on the wildcard pattern to improve compatibility with
-           multiple OCaml's parsetree versions *)
+      | Parsetree.Pmod_ident _
+      | Parsetree.Pmod_apply (_, _)
+      | Parsetree.Pmod_constraint (_, _)
+      | Parsetree.Pmod_unpack _ | Parsetree.Pmod_extension _ ->
         Ast_iterator.default_iterator.module_expr self module_expr
     in
     let class_declaration

ocaml-lsp-server/src/semantic_highlighting.ml

@@ -425,10 +425,9 @@ end = struct
     self.attributes self pld_attributes
   ;;
 
-  let value_binding
-    (self : Ast_iterator.iterator)
-    ({ pvb_pat; pvb_expr; pvb_attributes; _ } as vb : Parsetree.value_binding)
-    =
+  let value_binding (self : Ast_iterator.iterator)
+      ({ pvb_pat; pvb_expr; pvb_attributes; pvb_loc = _ } as vb :
+        Parsetree.value_binding) =
     match
       match pvb_pat.ppat_desc, pvb_expr.pexp_desc with
       | Parsetree.Ppat_var fn_name, _ ->
@@ -762,9 +761,7 @@ end = struct
           self.module_type self mt);
         `Custom_iterator
       | Pmod_extension _ -> `Custom_iterator
-      | _ ->
-        (* We rely on the wildcard pattern to improve compatibility with
-           multiple OCaml's parsetree versions *)
+      | Pmod_unpack _ | Pmod_apply (_, _) | Pmod_structure _ ->
         `Default_iterator
     with
     | `Custom_iterator -> self.attributes self pmod_attributes