LaTeX writer: Avoid inadvertently creating ?` or !` ligatures.

These are upside down ? and !, resp.

Closes #5407.

2 files changed, 22 insertions, 0 deletions

diff --git a/src/Text/Pandoc/Writers/LaTeX.hs b/src/Text/Pandoc/Writers/LaTeX.hs
index 0ef04db3f..d0c08815c 100644
--- a/src/Text/Pandoc/Writers/LaTeX.hs
+++ b/src/Text/Pandoc/Writers/LaTeX.hs
@@ -340,6 +340,14 @@ stringToLaTeX context zs = do
                              -> cs <> xs
             _ -> cs <> "{}" <> xs
     in case x of
+         '?' | ligatures ->  -- avoid ?` ligature
+           case xs of
+             '`':_ -> emits "?{}"
+             _     -> emitc x
+         '!' | ligatures ->  -- avoid !` ligature
+           case xs of
+             '`':_ -> emits "!{}"
+             _     -> emitc x
          '{' -> emits "\\{"
          '}' -> emits "\\}"
          '`' | ctx == CodeString -> emitcseq "\\textasciigrave"
diff --git a/test/command/5407.md b/test/command/5407.md
new file mode 100644
index 000000000..ac9bed29d
--- /dev/null
+++ b/test/command/5407.md
@@ -0,0 +1,14 @@
+```
+% pandoc -t latex --wrap=preserve
+hi there?“
+hi there!“
+hi there?‘
+hi there!‘
+hi there!
+^D
+hi there?{}``
+hi there!{}``
+hi there?{}`
+hi there!{}`
+hi there!
+```