Add test case for ocamllex + jbuild bug report

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>

test/blackbox-tests/dune.inc

@@ -570,6 +570,14 @@
    test-cases/ocamldep-multi-stanzas
    (progn (run %{exe:cram.exe} -test run.t) (diff? run.t run.t.corrected)))))
 
+(alias
+ (name ocamllex-jbuild)
+ (deps (package dune) (source_tree test-cases/ocamllex-jbuild))
+ (action
+  (chdir
+   test-cases/ocamllex-jbuild
+   (progn (run %{exe:cram.exe} -test run.t) (diff? run.t run.t.corrected)))))
+
 (alias
  (name odoc)
  (deps (package dune) (source_tree test-cases/odoc))
@@ -875,6 +883,7 @@
   (alias ocaml-config-macro)
   (alias ocaml-syntax)
   (alias ocamldep-multi-stanzas)
+  (alias ocamllex-jbuild)
   (alias odoc)
   (alias odoc-unique-mlds)
   (alias output-obj)
@@ -970,6 +979,7 @@
   (alias ocaml-config-macro)
   (alias ocaml-syntax)
   (alias ocamldep-multi-stanzas)
+  (alias ocamllex-jbuild)
   (alias output-obj)
   (alias package-dep)
   (alias path-variables)

test/blackbox-tests/test-cases/ocamllex-jbuild/foo.mll

@@ -0,0 +1,8 @@
+{}
+
+rule f = parse
+  | _ { () }
+
+{
+  print_endline "foo"
+}

test/blackbox-tests/test-cases/ocamllex-jbuild/jbuild

@@ -0,0 +1,5 @@
+(ocamllex
+ ((modules (foo))))
+
+(executable
+ ((name foo)))

test/blackbox-tests/test-cases/ocamllex-jbuild/run.t

@@ -0,0 +1,6 @@
+  $ dune exec ./foo.exe
+  File "jbuild", line 2, characters 3-10:
+   ((modules (foo))))
+     ^^^^^^^
+  Error: S-expression of the form (<name> <values>...) expected
+  [1]