From b466152d6185750438f7355701ae68186692d65b Mon Sep 17 00:00:00 2001
From: John MacFarlane <jgm@berkeley.edu>
Date: Sun, 11 Jun 2017 22:24:20 +0200
Subject: [PATCH] Don't allow backslash + newline to affect block structure.
Note that as a result of this change, the following,
which formerly produced a header with two lines separated
by a line break, will now produce a header followed by a
paragraph:
# Hi\
there
This may affect some existing documents that relied on
this undocumented and unintended behavior.
This change makes pandoc more consistent with other
Markdown implementations, and with itself (since the two-space
version of a line break doesn't work inside ATX headers, and
neither version works inside Setext headers).
Closes #3730.
---
src/Text/Pandoc/Readers/Markdown.hs | 11 ++++++++---
test/command/3730.md | 21 +++++++++++++++++++++
test/fb2/titles.fb2 | 2 +-
test/fb2/titles.markdown | 4 ----
4 files changed, 30 insertions(+), 8 deletions(-)
create mode 100644 test/command/3730.md
diff --git a/src/Text/Pandoc/Readers/Markdown.hs b/src/Text/Pandoc/Readers/Markdown.hs
index 5e966a17e..e1c481311 100644
--- a/src/Text/Pandoc/Readers/Markdown.hs
+++ b/src/Text/Pandoc/Readers/Markdown.hs
@@ -1451,6 +1451,7 @@ inline = choice [ whitespace
, autoLink
, spanHtml
, rawHtmlInline
+ , escapedNewline
, escapedChar
, rawLaTeXInline'
, exampleRef
@@ -1467,16 +1468,20 @@ escapedChar' = try $ do
(guardEnabled Ext_all_symbols_escapable >> satisfy (not . isAlphaNum))
<|> (guardEnabled Ext_angle_brackets_escapable >>
oneOf "\\`*_{}[]()>#+-.!~\"<>")
- <|> (guardEnabled Ext_escaped_line_breaks >> char '\n')
<|> oneOf "\\`*_{}[]()>#+-.!~\""
+escapedNewline :: PandocMonad m => MarkdownParser m (F Inlines)
+escapedNewline = try $ do
+ guardEnabled Ext_escaped_line_breaks
+ char '\\'
+ lookAhead (char '\n') -- don't consume the newline (see #3730)
+ return $ return B.linebreak
+
escapedChar :: PandocMonad m => MarkdownParser m (F Inlines)
escapedChar = do
result <- escapedChar'
case result of
' ' -> return $ return $ B.str "\160" -- "\ " is a nonbreaking space
- '\n' -> guardEnabled Ext_escaped_line_breaks >>
- return (return B.linebreak) -- "\[newline]" is a linebreak
_ -> return $ return $ B.str [result]
ltSign :: PandocMonad m => MarkdownParser m (F Inlines)
diff --git a/test/command/3730.md b/test/command/3730.md
new file mode 100644
index 000000000..fbc06cbce
--- /dev/null
+++ b/test/command/3730.md
@@ -0,0 +1,21 @@
+````
+% pandoc
+nice line\
+```
+code
+```
+^D
+<p>nice line<br />
+</p>
+<pre><code>code</code></pre>
+````
+
+```
+% pandoc
+# hi\
+there
+^D
+<h1 id="hi">hi<br />
+</h1>
+<p>there</p>
+```
diff --git a/test/fb2/titles.fb2 b/test/fb2/titles.fb2
index 9e8d47e36..0a3b1404e 100644
--- a/test/fb2/titles.fb2
+++ b/test/fb2/titles.fb2
@@ -1,3 +1,3 @@
<?xml version="1.0" encoding="UTF-8"?>
-<FictionBook xmlns="http://www.gribuser.ru/xml/fictionbook/2.0" xmlns:l="http://www.w3.org/1999/xlink"><description><title-info /><document-info><program-used>pandoc</program-used></document-info></description><body><title><p /></title><annotation><p></p></annotation><section><title><p>Simple title</p></title><p>This example tests if Pandoc doesn’t insert forbidden elements in FictionBook titles.</p></section><section><title><p>Emphasized Strong Title</p></title></section><section><title><p>Title with</p><empty-line /><p>line break</p></title></section></body></FictionBook>
+<FictionBook xmlns="http://www.gribuser.ru/xml/fictionbook/2.0" xmlns:l="http://www.w3.org/1999/xlink"><description><title-info /><document-info><program-used>pandoc</program-used></document-info></description><body><title><p /></title><annotation><p></p></annotation><section><title><p>Simple title</p></title><p>This example tests if Pandoc doesn’t insert forbidden elements in FictionBook titles.</p></section><section><title><p>Emphasized Strong Title</p></title></section></body></FictionBook>
diff --git a/test/fb2/titles.markdown b/test/fb2/titles.markdown
index cc3d0e0d0..1eaf2ccd5 100644
--- a/test/fb2/titles.markdown
+++ b/test/fb2/titles.markdown
@@ -4,7 +4,3 @@ This example tests if Pandoc doesn't insert forbidden elements in FictionBook ti
# *Emphasized* **Strong** Title
-# Title with\
-line break
-
-