Raise a SongSyntaxError on fatal error

patacrep/songs/chordpro/syntax.py

@@ -7,6 +7,7 @@ import re
 from patacrep.songs.syntax import Parser
 from patacrep.songs.chordpro import ast
 from patacrep.songs.chordpro.lexer import tokens, ChordProLexer
+from patacrep.songs import errors
 
 LOGGER = logging.getLogger()
 
@@ -331,5 +332,15 @@ def parse_song(content, filename=None):
         # TODO: Provide a nicer error (an empty song?)
         # TODO: Add an error to the song.errors list.
         #       using parser._errors
-        raise SyntaxError('Fatal error during song parsing: {}'.format(filename))
+
+        # pylint: disable=protected-access
+        if parser._errors:
+            # The line where it started to go wrong
+            lineno = parser._errors[-1].line
+        else:
+            lineno = None
+        raise errors.SongSyntaxError(
+            message='Fatal error during song parsing: {}'.format(filename),
+            line=lineno,
+            )
     return parsed_content

patacrep/songs/errors.py

@@ -1,12 +1,13 @@
 """Errors in song definition (syntax errors, and so on)"""
 
-class SongError:
+class SongError(Exception):
     """Generic song error"""
     # pylint: disable=too-few-public-methods
 
     type = "generic"
 
     def __init__(self, message):
+        super().__init__()
         self.message = message
 
     def __str__(self):

test/test_chordpro/test_parser.py

@@ -11,6 +11,7 @@ from pkg_resources import resource_filename
 from patacrep import files
 from patacrep.build import DEFAULT_CONFIG
 from patacrep.encoding import open_read
+from patacrep.songs import errors
 
 from .. import disable_logging
 from .. import dynamic # pylint: disable=unused-import
@@ -119,7 +120,7 @@ class FileTest(unittest.TestCase, metaclass=dynamic.DynamicTest):
             sourcename = "{}.{}.source".format(base, in_format)
             with self.chdir('errors'):
                 parser = self.song_plugins[out_format][in_format]
-                self.assertRaises(SyntaxError, parser, sourcename, self.config)
+                self.assertRaises(errors.SongSyntaxError, parser, sourcename, self.config)
 
         test_parse_failure.__doc__ = (
             "Test that '{base}' parsing fails."