Added a -e option to random that makes the distribution even among artists

beetsplug/random.py

@@ -19,6 +19,8 @@ from beets.plugins import BeetsPlugin
 from beets.ui import Subcommand, decargs, print_obj
 from beets.util.functemplate import Template
 import random
+from operator import attrgetter
+from itertools import groupby
 
 def random_item(lib, opts, args):
     query = decargs(args)
@@ -32,9 +34,19 @@ def random_item(lib, opts, args):
         objs = list(lib.albums(query=query))
     else:
         objs = list(lib.items(query=query))
+    if opts.equal_chance:
+        key = attrgetter('albumartist')
+        objs.sort(key=key)
+        # Now the objs are list of albums or items
+        objs = [list(v) for k, v in groupby(objs, key)]
+
     number = min(len(objs), opts.number)
     objs = random.sample(objs, number)
 
+    if opts.equal_chance:
+        # Select one random item from that artist
+        objs = map(random.choice, objs)
+
     for item in objs:
         print_obj(item, lib, template)
 
@@ -48,6 +60,8 @@ random_cmd.parser.add_option('-f', '--format', action='store',
         help='print with custom format', default=None)
 random_cmd.parser.add_option('-n', '--number', action='store', type="int",
         help='number of objects to choose', default=1)
+random_cmd.parser.add_option('-e', '--equal-chance', action='store_true',
+        help='each artist has the same chance')
 random_cmd.func = random_item
 
 class Random(BeetsPlugin):

docs/plugins/random.rst

@@ -16,6 +16,10 @@ command (see :doc:`/reference/cli`). To choose an album instead of a single
 track, use ``-a``; to print paths to items instead of metadata, use ``-p``; and
 to use a custom format for printing, use ``-f FORMAT``.
 
+If the ``-e`` option is passed, the random choice will be even among
+artists (the albumartist field) This makes sure that your antholofgy
+of Bob Dylan won't make you listen to Bob Dylan 50% of the time.
+
 The ``-n NUMBER`` option controls the number of objects that are selected and
 printed (default 1). To select 5 tracks from your library, type ``beet random
 -n5``.