From df93e4533d1c25d707f8a135480f4e7ba54f85e5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bj=C3=B6rn=20Lindqvist?= <bjourne@gmail.com>
Date: Fri, 11 Mar 2016 09:44:42 +0100
Subject: [PATCH] graphviz.dot: fix escaping logic

It used escape the escape char \, but it shouldn't do that because it
leads to double escaping.
---
 extra/graphviz/dot/dot-tests.factor | 21 +++++++++++++++++++++
 extra/graphviz/dot/dot.factor       | 10 +++++++---
 2 files changed, 28 insertions(+), 3 deletions(-)
 create mode 100644 extra/graphviz/dot/dot-tests.factor

diff --git a/extra/graphviz/dot/dot-tests.factor b/extra/graphviz/dot/dot-tests.factor
new file mode 100644
index 0000000000..190b9361a9
--- /dev/null
+++ b/extra/graphviz/dot/dot-tests.factor
@@ -0,0 +1,21 @@
+USING: graphviz.dot.private io.streams.string sequences tools.test ;
+IN: graphviz.dot.tests
+
+! Making sure strings are escaped properly
+{
+    {
+        "\"BAH\" "
+        "\"LINE1\\nLINE2\" "
+        "\"\\lLINE1\\lLINE2\" "
+        "\"hum\\\"ho\\\"\" "
+    }
+} [
+    {
+        "BAH"
+        "LINE1\\nLINE2"
+        "\\lLINE1\\lLINE2"
+        "hum\"ho\""
+    } [
+        [ dot. ] with-string-writer
+    ] map
+] unit-test
diff --git a/extra/graphviz/dot/dot.factor b/extra/graphviz/dot/dot.factor
index 82109cc87b..48677794b8 100644
--- a/extra/graphviz/dot/dot.factor
+++ b/extra/graphviz/dot/dot.factor
@@ -1,8 +1,8 @@
 ! Copyright (C) 2012 Alex Vondrak.
 ! See http://factorcode.org/license.txt for BSD license.
 USING: accessors classes classes.tuple combinators formatting graphviz
-graphviz.attributes io io.files kernel namespaces prettyprint.backend
-sequences splitting strings words ;
+graphviz.attributes io io.files kernel namespaces sequences splitting
+strings words ;
 IN: graphviz.dot
 
 <PRIVATE
@@ -14,8 +14,12 @@ GENERIC: dot. ( obj -- )
 ! option in case there's a keyword clash, spaces in the ID,
 ! etc.  This does mean that HTML labels aren't supported, but
 ! they don't seem to work using the Graphviz API anyway.
+!
+! Special escaping logic is required here because of the \l escape
+! sequence.
 : quote-string ( str -- str' )
-    "\"" "\"" unparse-string "\0" split "" join ;
+    { { "\"" "\\\"" } { "\0" "" } } [ first2 replace ] each
+    "\"" "\"" surround ;
 
 M: string dot. quote-string "%s " printf ;