Verify rewriter and runtime linkage through explicit interfaces

smoke.sh

@@ -0,0 +1,33 @@
+#!/bin/sh
+set -eu
+compiler=${OCAMLC:-ocamlc}
+rewriter=$(cd "$(dirname "$1")" && pwd)/$(basename "$1")
+library=$(cd "$2" && pwd)
+directory=$(mktemp -d)
+trap 'rm -rf "$directory"' EXIT HUP INT TERM
+
+cat > "$directory/unit.mli" <<'ML'
+type t = { colour : string; label : string }
+val colour : t -> string
+val set_colour : string -> t -> t
+val _colour : (t -> string) * (string -> t -> t)
+ML
+
+cat > "$directory/unit.ml" <<'ML'
+type t = { colour : string; label : string } [@@fieldglass generate]
+ML
+
+cat > "$directory/client.ml" <<'ML'
+let () =
+  let original = Unit.{ colour = "grey"; label = "sample" } in
+  let changed = Fieldglass.over Unit._colour ~f:String.uppercase_ascii original in
+  assert (Unit.colour changed = "GREY");
+  assert (changed.Unit.label = original.Unit.label);
+  assert (Unit.colour original = "grey")
+ML
+
+"$compiler" -c "$directory/unit.mli"
+"$compiler" -I "$directory" -ppx "$rewriter" -c "$directory/unit.ml"
+"$compiler" -I "$library" -I "$directory" "$library/fieldglass.cma" \
+  "$directory/unit.cmo" "$directory/client.ml" -o "$directory/client.byte"
+"$directory/client.byte"