From e7a68fc7e82028dbf66f25350b45875fbe634db6 Mon Sep 17 00:00:00 2001
From: John MacFarlane <fiddlosopher@gmail.com>
Date: Mon, 1 Jul 2013 20:56:27 -0700
Subject: Markdown writer: Render yaml title block fields in alpha order.

This makes the output predictable; previously it varied across
implementations.
---
 src/Text/Pandoc/Writers/Markdown.hs | 5 +++--
 tests/writer.markdown               | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/Text/Pandoc/Writers/Markdown.hs b/src/Text/Pandoc/Writers/Markdown.hs
index 1715f0af1..aa29ebce1 100644
--- a/src/Text/Pandoc/Writers/Markdown.hs
+++ b/src/Text/Pandoc/Writers/Markdown.hs
@@ -38,7 +38,8 @@ import Text.Pandoc.Shared
 import Text.Pandoc.Writers.Shared
 import Text.Pandoc.Options
 import Text.Pandoc.Parsing hiding (blankline, char, space)
-import Data.List ( group, isPrefixOf, find, intersperse, transpose )
+import Data.List ( group, isPrefixOf, find, intersperse, transpose, sortBy )
+import Data.Ord ( comparing )
 import Text.Pandoc.Pretty
 import Control.Monad.State
 import qualified Data.Set as Set
@@ -127,7 +128,7 @@ jsonToYaml (Object hashmap) =
                (k', Object _, x)  -> (k' <> ":") $$ nest 2 x
                (_, String "", _)  -> empty
                (k', _, x)         -> k' <> ":" <> space <> x)
-       $ H.toList hashmap
+       $ sortBy (comparing fst) $ H.toList hashmap
 jsonToYaml (Array vec) =
   vcat $ map (\v -> hang 2 "- " (jsonToYaml v)) $ V.toList vec
 jsonToYaml (String "") = empty
diff --git a/tests/writer.markdown b/tests/writer.markdown
index 6691836a3..9db6ae452 100644
--- a/tests/writer.markdown
+++ b/tests/writer.markdown
@@ -1,8 +1,8 @@
 ---
-date: 'July 17, 2006'
 author:
 - John MacFarlane
 - Anonymous
+date: 'July 17, 2006'
 title: Pandoc Test Suite
 ...
 
-- 
cgit v1.2.3