Introduce %I (MusicBrainz Disc ID) template variable

Signed-off-by: JoeLametta <JoeLametta@users.noreply.github.com>

man/whipper-cd-rip.rst

@@ -98,6 +98,7 @@ Template schemes
 | - %C: release catalog number
 | - %d: release title (with disambiguation)
 | - %D: disc title (without disambiguation)
+| - %I: MusicBrainz Disc ID
 | - %y: release year
 | - %r: release type, lowercase
 | - %R: release type, normal case

whipper/command/cd.py

@@ -58,6 +58,7 @@ disc and track template are:
  - %C: release catalog number
  - %d: release title (with disambiguation)
  - %D: disc title (without disambiguation)
+ - %I: MusicBrainz Disc ID
  - %y: release year
  - %r: release type, lowercase
  - %R: release type, normal case

whipper/common/common.py

@@ -277,9 +277,9 @@ def getRelativePath(targetPath, collectionPath):
 def validate_template(template, kind):
     """Raise exception if disc/track template includes invalid variables."""
     if kind == 'disc':
-        matches = re.findall(r'%[^ABCDRSXdrxy]', template)
+        matches = re.findall(r'%[^ABCDIRSXdrxy]', template)
     elif kind == 'track':
-        matches = re.findall(r'%[^ABCDRSXadnrstxy]', template)
+        matches = re.findall(r'%[^ABCDIRSXadnrstxy]', template)
     if '%' in template and matches:
         raise ValueError(kind + ' template string contains invalid '
                          'variable(s): {}'.format(', '.join(matches)))

whipper/common/program.py

@@ -180,6 +180,7 @@ class Program:
         * ``%C``: release catalog number
         * ``%d``: release title (with disambiguation)
         * ``%D``: disc title (without disambiguation)
+        * ``%I``: MusicBrainz Disc ID
         * ``%y``: release year
         * ``%r``: release type, lowercase
         * ``%R``: release type, normal case
@@ -190,7 +191,7 @@ class Program:
         assert isinstance(template, str), "%r is not str" % template
         v = {}
         v['A'] = 'Unknown Artist'
-        v['d'] = v['D'] = mbdiscid  # fallback for title
+        v['I'] = v['d'] = v['D'] = mbdiscid  # fallback for title
         v['r'] = 'unknown'
         v['R'] = 'Unknown'
         v['B'] = ''  # barcode