add tests for the TagCache, fix a bug, docs, drop unneeded sorted..

ui/medashare/cli.py

@@ -749,9 +749,12 @@ def enumeratedir(_dir, created_by_ref):
 	    os.path.isdir(os.path.join(_dir, x)) ]
 
 class TagCache:
+	'''Takes tuples, and stores them in a cache where only
+	the most count recent ones are kept.'''
+
 	def __init__(self, tags=(), count=10):
 		self._cache = dict((x, None) for x in tags)
-		self._count = 10
+		self._count = count
 		self._modified = False
 
 	@property
@@ -762,6 +765,9 @@ class TagCache:
 		return self._modified
 
 	def add(self, tag):
+		'''Add a tag (tuple) to the cache, possibly dropping ann older
+		tag if necessary.'''
+
 		self._modified = True
 
 		try:
@@ -771,14 +777,19 @@ class TagCache:
 
 		self._cache[tag] = None
 
-		if len(self._cache) > self._count:
-			del self._cache[next(iter(a.keys()))]
+		while len(self._cache) > self._count:
+			del self._cache[next(iter(self._cache.keys()))]
 
 	def tags(self):
+		'''Returns the sorted list of tags in the cache.'''
+
 		return sorted(self._cache.keys())
 
 	@classmethod
 	def load(cls, fname):
+		'''Load the cache from fname.  Must be previously have saved
+		using the store method.'''
+
 		try:
 			with open(fname, 'rb') as fp:
 				cache = _asn1coder.loads(fp.read())
@@ -792,13 +803,66 @@ class TagCache:
 		return cls(**cache)
 
 	def store(self, fname):
+		'''Store the cache to fname.  The modified property will
+		be cleared after this.'''
+
 		self._modified = False
 
-		cache = dict(tags=list(self._cache.keys()))
+		cache = dict(tags=list(self._cache.keys()), count=self._count)
 
 		with open(fname, 'wb') as fp:
 			fp.write(_asn1coder.dumps(cache))
 
+class _TestTagCache(unittest.TestCase):
+	def setUp(self):
+		d = pathlib.Path(tempfile.mkdtemp()).resolve()
+		self.basetempdir = d
+
+		self.tempdir = d / 'subdir'
+
+		self.tempdir.mkdir()
+
+	def tearDown(self):
+		shutil.rmtree(self.basetempdir)
+		self.tempdir = None
+
+	def test_cache(self):
+		# test basic functionality
+		tc = TagCache(count=2)
+
+		self.assertFalse(tc.modified)
+
+		tc.add(('foo', 'foo'))
+
+		self.assertTrue(tc.modified)
+
+		tc.add(('bar', 'bar'))
+
+		self.assertEqual(tc.tags(), [ ('bar', 'bar'), ('foo', 'foo') ])
+
+		tc.add(('foo', 'foo'))
+
+		tc.add(('baz', 'baz'))
+
+		tc.add(('foo', 'foo'))
+
+		self.assertEqual(tc.tags(), [ ('baz', 'baz'), ('foo', 'foo') ])
+
+		cachefile = self.tempdir / 'somecache'
+		tc.store(cachefile)
+
+		self.assertFalse(tc.modified)
+
+		ntc = TagCache.load(cachefile)
+
+		self.assertFalse(ntc.modified)
+
+		self.assertEqual(tc.tags(), [ ('baz', 'baz'), ('foo', 'foo') ])
+
+		ntc.add(('whee', 'whee'))
+
+		self.assertEqual(ntc.tags(), [ ('foo', 'foo'), ('whee', 'whee') ])
+
 def _get_paths(options):
 	fnames = (
 	    '.medashare_identity.pasn1',
@@ -1158,7 +1222,7 @@ def cmd_interactive(options, persona, objstr, cache):
 		print('7) Open file.')
 		print('8) Turn auto skip %s' % 'off' if autoskip else 'on')
 
-		tags = sorted(cache.tags())
+		tags = cache.tags()
 
 		for pos, (tag, value) in enumerate(tags):
 			print('%s) %s=%s' % (string.ascii_lowercase[pos], tag, value))

ui/medashare/tests.py

@@ -2,6 +2,6 @@ from .btv import _TestCases as btv_test_cases
 from .btv.bencode import _TestCases as bencode_test_cases
 from .mdb import _TestJSONEncoder
 from .cli import _TestCononicalCoder, _TestCases as cli_test_cases
-from .cli import _TestMigrations
+from .cli import _TestMigrations, _TestTagCache
 from .mtree import Test
 from .server import _TestCases, _TestPostConfig