unikernel/duniverse/ppxlib/test/expand-header-and-footer/dune

@@ -0,0 +1,14 @@
+(rule
+ (package ppxlib)
+ (alias runtest)
+ (enabled_if
+  (>= %{ocaml_version} "4.09.0"))
+ (deps
+  (:test test.ml)
+  (package ppxlib))
+ (action
+  (chdir
+   %{project_root}
+   (progn
+    (run expect-test %{test})
+    (diff? %{test} %{test}.corrected)))))

unikernel/duniverse/ppxlib/test/expand-header-and-footer/test.ml

@@ -0,0 +1,27 @@
+open Stdppx
+open Ppxlib
+
+let _ =
+  let loc = Location.none in
+  let extension =
+    Extension.V3.declare_inline
+      "include"
+      Structure_item
+      Ast_pattern.(pstr __)
+      (fun ~ctxt:_ x -> x)
+  in
+  let rules = [ Context_free.Rule.extension extension ] in
+  let enclose_impl _ _ = [%str [%%include let a = 1]], [%str [%%include let c = 3]] in
+  Driver.V2.register_transformation ~rules ~enclose_impl "example"
+
+[%%expect{|
+- : unit = ()
+|}]
+
+let b = 2
+
+[%%expect{|
+val a : int = 1
+val b : int = 2
+val c : int = 3
+|}]