unikernel/duniverse/ppxlib/test/driver/non-compressible-suffix/dune

@@ -0,0 +1,14 @@
+(rule
+ (package ppxlib)
+ (alias runtest)
+ (enabled_if
+  (>= %{ocaml_version} "4.08.0"))
+ (deps
+  (:test test.ml)
+  (package ppxlib))
+ (action
+  (chdir
+   %{project_root}
+   (progn
+    (run expect-test %{test})
+    (diff? %{test} %{test}.corrected)))))

unikernel/duniverse/ppxlib/test/driver/non-compressible-suffix/test.ml

@@ -0,0 +1,35 @@
+open Ppxlib;;
+open Ast_builder.Default;;
+
+Driver.register_transformation "blah"
+  ~rules:[ Context_free.Rule.extension
+             (Extension.declare "foo"
+                Expression
+                Ast_pattern.(pstr nil)
+                (fun ~loc ~path:_ -> eint ~loc 42))
+         ; Context_free.Rule.extension
+             (Extension.declare "@foo.bar"
+                Expression
+                Ast_pattern.(pstr nil)
+                (fun ~loc ~path:_ -> eint ~loc 42))
+         ]
+;;
+[%%expect{|
+- : unit = ()
+|}]
+
+[%foo];;
+[%%expect{|
+- : int = 42
+|}]
+
+[%foo.bar];;
+[%%expect{|
+- : int = 42
+|}]
+
+[%bar];;
+[%%expect{|
+Line _, characters 2-5:
+Error: Uninterpreted extension 'bar'.
+|}]