unikernel/duniverse/dune_/test/unit-tests/sexp_tests.ml

@@ -0,0 +1,52 @@
+open! Stdune
+
+let () = Printexc.record_backtrace true
+
+(* Test that all strings of length <= 3 such that [Dune_lang.Atom.is_valid s]
+   are recognized as atoms by the parser *)
+
+let () =
+  for len = 0 to 3 do
+    let s = Bytes.create len in
+    for i = 0 to (1 lsl (len * 8)) - 1 do
+      if len > 0 then Bytes.set s 0 (Char.chr (i land 0xff));
+      if len > 1 then Bytes.set s 1 (Char.chr ((i lsr 4) land 0xff));
+      if len > 2 then Bytes.set s 2 (Char.chr ((i lsr 8) land 0xff));
+      let s = Bytes.unsafe_to_string s in
+      let parser_recognizes_as_atom =
+        match Dune_lang.Parser.parse_string ~fname:"" ~mode:Single s with
+        | exception _ -> false
+        | Atom (_, A s') -> s = s'
+        | _ -> false
+      in
+      let printed_as_atom =
+        match Dune_lang.atom_or_quoted_string s with
+        | Atom _ -> true
+        | _ -> false
+      in
+      let valid_dune_atom = Dune_lang.Atom.is_valid s in
+      if valid_dune_atom <> parser_recognizes_as_atom
+      then (
+        Printf.eprintf
+          "Dune_lang.Atom.is_valid error:\n\
+           - s = %S\n\
+           - Dune_lang.Atom.is_valid s = %B\n\
+           - parser_recognizes_as_atom = %B\n"
+          s
+          valid_dune_atom
+          parser_recognizes_as_atom;
+        exit 1);
+      if printed_as_atom && not parser_recognizes_as_atom
+      then (
+        Printf.eprintf
+          "Dune_lang.Atom.atom_or_quoted_string error:\n\
+           - s = %S\n\
+           - printed_as_atom = %B\n\
+           - parser_recognizes_as_atom = %B\n"
+          s
+          printed_as_atom
+          parser_recognizes_as_atom;
+        exit 1)
+    done
+  done
+;;