test: demonstrate wrong compilation of option type match (#1522)

Author: anmonteiro

test/blackbox-tests/wrong-option-compilation.t

@@ -0,0 +1,31 @@
+
+  $ . ./setup.sh
+
+  $ cat > x.ml <<EOF
+  > let foo a =
+  >   let a = Some a in
+  >   match a with
+  >   | Some true -> "it's true"
+  >   | _ -> "it's false"
+  > let () = Js.log (foo false)
+  > EOF
+
+  $ melc x.ml | tee x.js
+  // Generated by Melange
+  'use strict';
+  
+  
+  function foo(a) {
+    return "it's true";
+  }
+  
+  console.log("it's true");
+  
+  module.exports = {
+    foo,
+  }
+  /*  Not a pure module */
+
+  $ node x.js
+  it's true
+