Use unidecode to get the first letter for the index

patacrep/content/sort.py

@@ -5,27 +5,17 @@ to a songbook.
 """
 
 import logging
-import unidecode
 
 from patacrep import files
 from patacrep.content import ContentError
 from patacrep.content import process_content, validate_parser_argument
 from patacrep.content.song import OnlySongsError
+from patacrep.utils import normalize_string
 
 LOGGER = logging.getLogger(__name__)
 
 DEFAULT_SORT = ['by', 'album', 'title']
 
-def normalize_string(string):
-    """Return a normalized string.
-
-    Normalized means:
-    - no surrounding spaces;
-    - lower case;
-    - passed through unidecode.unidecode().
-    """
-    return unidecode.unidecode(string.lower().strip())
-
 def normalize_field(field):
     """Return a normalized field, it being a string or a list of strings."""
     if isinstance(field, str):

patacrep/index.py

@@ -7,11 +7,11 @@ from a file generated by the latex compilation of the songbook (.sxd).
 
 import locale
 import re
-import unidecode
 
 from patacrep import authors
 from patacrep import encoding
 from patacrep.latex import tex2plain
+from patacrep.utils import normalize_string
 
 EOL = "\n"
 
@@ -67,7 +67,7 @@ class Index:
     def get_first_letter(key):
         """Return the uppercase first letter of key."""
         try:
-            letter = FIRST_LETTER_PATTERN.match(key).group(1)
+            letter = FIRST_LETTER_PATTERN.match(normalize_string(key)).group(1)
         except AttributeError:
             # classify as number all the non letter characters
             letter = "0"
@@ -108,7 +108,7 @@ class Index:
         if key not in self.data[first]:
             self.data[first][key] = {
                 'sortingkey': [
-                    unidecode.unidecode(tex2plain(item)).lower()
+                    normalize_string(tex2plain(item))
                     for item in key
                     ],
                 'entries': [],

patacrep/utils.py

@@ -1,6 +1,7 @@
 """Some utility functions"""
 
 from collections import UserDict
+import unidecode
 
 from patacrep import errors, Rx
 
@@ -92,3 +93,13 @@ def validate_yaml_schema(data, schema):
         schema.validate(data)
     except Rx.SchemaMismatch as exception:
         raise errors.SchemaError(rx_exception=exception)
+
+def normalize_string(string):
+    """Return a normalized string.
+
+    Normalized means:
+    - no surrounding spaces;
+    - lower case;
+    - passed through unidecode.unidecode().
+    """
+    return unidecode.unidecode(string.lower().strip())