[WIP] Escaping characters when generating chordpro files works.

patacrep/data/templates/songs/chordpro/chordpro/content_word

@@ -1 +1 @@
-(( content.value ))
+(( content.value|escape_specials('{}\\#') ))

patacrep/data/templates/songs/chordpro/chordpro/song_header

@@ -9,16 +9,16 @@
 (* endif *)
 
 (*- for title in titles -*)
-  {title: (( title ))}
+  {title: (( title|escape_specials('{}\\') ))}
 (* endfor -*)
 
 (*- for author in authors -*)
-  {artist: (( author[1] )) (( author[0] ))}
+  {artist: (( author[1]|escape_specials('{}\\') )) (( author[0]|escape_specials('{}\\') ))}
 (* endfor -*)
 
 (*- for key in ['album', 'copyright'] *)
   (* if key in metadata -*)
-    {(( key )): (( metadata[key] ))}
+    {(( key )): (( metadata[key]|escape_specials('{}\\') ))}
   (* endif *)
 (* endfor *)
 (* if 'cover' in metadata -*)
@@ -30,7 +30,7 @@
 (* endfor -*)
 
 (*- for key in metadata.morekeys -*)
-  {key: (( key.keyword )): (( key.argument ))}
+  {key: (( key.keyword )): (( key.argument|escape_specials('{}\\') ))}
 (* endfor *)
 
 (*- for chord in metadata['define'] *)

patacrep/songs/chordpro/__init__.py

@@ -30,6 +30,7 @@ class ChordproSong(Song):
     # pylint: disable=abstract-method
 
     output_language = None
+    _translation_map = {}
 
     def _parse(self):
         """Parse content, and return the dictionary of song data."""
@@ -50,6 +51,7 @@ class ChordproSong(Song):
         filters.update({
             'search_image': self.search_image,
             'search_partition': self.search_partition,
+            'escape_specials': self._escape_specials,
         })
         return filters
 
@@ -84,6 +86,13 @@ class ChordproSong(Song):
         context.vars['content'] = content
         return context.environment.get_template(content.template()).render(context)
 
+    def _escape_specials(self, content, chars):
+        return str(content).translate(str.maketrans({
+            key: value
+            for key, value in self._translation_map.items()
+            if key in chars
+            }))
+
 class Chordpro2HtmlSong(ChordproSong):
     """Render chordpro song to html code"""
 
@@ -164,6 +173,12 @@ class Chordpro2ChordproSong(ChordproSong):
     """Render chordpro song to chordpro code"""
 
     output_language = "chordpro"
+    _translation_map = {
+        '{': r'\{',
+        '}': r'\}',
+        '\\': '\\\\',
+        '#': r'\#',
+    }
 
     def search_file(self, filename, extensions=None, *, datadirs=None):
         # pylint: disable=unused-variable

test/test_song/latex.csg

@@ -1,10 +1,12 @@
 {lang: en}
 {title: & $ % # _ \} \{ ~ ^ \\}
-{artist:  & $ % # _ \} \{ ~ ^ \\}
+{artist: & $ % # _ \} \{ ~ ^ \\}
 {album: & $ % # _ \} \{ ~ ^ \\}
 
+
 & $ % \# _ \} \{ ~ ^ \\
 
+
 {start_of_chorus}
     & $ % \# _ \} \{ ~ ^ \\
 {end_of_chorus}