From 1c2ca922affc6e1eea1fe4dc60f64304e9ac9a97 Mon Sep 17 00:00:00 2001
From: Sebastian Ullrich <sebasti@nullri.ch>
Date: Mon, 30 Jul 2018 14:42:59 -0700
Subject: [PATCH] test(tests/lean/reader1): test for perfect roundtripping

---
 tests/lean/reader1.lean | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tests/lean/reader1.lean b/tests/lean/reader1.lean
index 75a5a09dd0..2c74fa7e9f 100644
--- a/tests/lean/reader1.lean
+++ b/tests/lean/reader1.lean
@@ -4,6 +4,10 @@ open lean.parser.reader
 
 def show_result (p : lean.parser.reader) (s : string) : io unit :=
 let (stx, errors) := p.parse ⟨⟩ s in
+when (stx.reprint ≠ s) (
+  io.print_ln "reprint fail:" *>
+  io.print_ln stx.reprint
+) *>
 match errors with
 | [] := do
   io.print_ln "result: ",