From 849311af001dc42b2bc999e4d5c6698f5ab03f11 Mon Sep 17 00:00:00 2001
From: Leonardo de Moura <leonardo@microsoft.com>
Date: Thu, 8 Aug 2019 10:47:19 -0700
Subject: [PATCH] test(tests/playground/patch): do-nothing transformer

---
 tests/playground/patch.lean | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
 create mode 100644 tests/playground/patch.lean

diff --git a/tests/playground/patch.lean b/tests/playground/patch.lean
new file mode 100644
index 0000000000..3f45a83c98
--- /dev/null
+++ b/tests/playground/patch.lean
@@ -0,0 +1,16 @@
+import init.lean.parser
+open Lean
+open Lean.Parser
+
+def fixEqnSyntax (stx : Syntax) : Syntax :=
+stx
+
+def main (xs : List String) : IO Unit :=
+do
+[fname] ← pure xs | throw (IO.userError "usage `patch <file-name>`");
+env ← mkEmptyEnvironment;
+stx ← parseFile env fname;
+let stx := fixEqnSyntax stx;
+match stx.reprint with
+| some out => IO.print out
+| none     => throw (IO.userError "failed to reprint")