--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/test-filecache.py	Sat Jul 09 19:06:59 2011 +0300
@@ -0,0 +1,95 @@
+import sys, os, subprocess
+
+try:
+    subprocess.check_call(['%s/hghave' % os.environ['TESTDIR'], 'cacheable'])
+except subprocess.CalledProcessError:
+    sys.exit(80)
+
+from mercurial import util, scmutil, extensions
+
+filecache = scmutil.filecache
+
+class fakerepo(object):
+    def __init__(self):
+        self._filecache = {}
+
+    def join(self, p):
+        return p
+
+    def sjoin(self, p):
+        return p
+
+    @filecache('x')
+    def cached(self):
+        print 'creating'
+
+    def invalidate(self):
+        for k in self._filecache:
+            try:
+                delattr(self, k)
+            except AttributeError:
+                pass
+
+def basic(repo):
+    # file doesn't exist, calls function
+    repo.cached
+
+    repo.invalidate()
+    # file still doesn't exist, uses cache
+    repo.cached
+
+    # create empty file
+    f = open('x', 'w')
+    f.close()
+    repo.invalidate()
+    # should recreate the object
+    repo.cached
+
+    f = open('x', 'w')
+    f.write('a')
+    f.close()
+    repo.invalidate()
+    # should recreate the object
+    repo.cached
+
+    repo.invalidate()
+    # stats file again, nothing changed, reuses object
+    repo.cached
+
+    # atomic replace file, size doesn't change
+    # hopefully st_mtime doesn't change as well so this doesn't use the cache
+    # because of inode change
+    f = scmutil.opener('.')('x', 'w', atomictemp=True)
+    f.write('b')
+    f.rename()
+
+    repo.invalidate()
+    repo.cached
+
+def fakeuncacheable():
+    def wrapcacheable(orig, *args, **kwargs):
+        return False
+
+    def wrapinit(orig, *args, **kwargs):
+        pass
+
+    originit = extensions.wrapfunction(util.cachestat, '__init__', wrapinit)
+    origcacheable = extensions.wrapfunction(util.cachestat, 'cacheable', wrapcacheable)
+
+    try:
+        os.remove('x')
+    except:
+        pass
+
+    basic(fakerepo())
+
+    util.cachestat.cacheable = origcacheable
+    util.cachestat.__init__ = originit
+
+print 'basic:'
+print
+basic(fakerepo())
+print
+print 'fakeuncacheable:'
+print
+fakeuncacheable()