--- a/mercurial/unionrepo.py	Tue Jan 12 13:10:31 2016 -0800
+++ b/mercurial/unionrepo.py	Wed Jan 13 15:47:37 2016 -0600
@@ -183,7 +183,8 @@
         """Check if a revision is censored."""
         if rev <= self.repotiprev:
             return filelog.filelog.iscensored(self, rev)
-        return self.revlog2.iscensored(rev)
+        node = self.node(rev)
+        return self.revlog2.iscensored(self.revlog2.rev(node))
 
 class unionpeer(localrepo.localpeer):
     def canpush(self):

--- a/tests/test-unionrepo.t	Tue Jan 12 13:10:31 2016 -0800
+++ b/tests/test-unionrepo.t	Wed Jan 13 15:47:37 2016 -0600
@@ -148,3 +148,22 @@
   2:68c0685446a3  repo1-2
   1:8a58db72e69d  repo1-1
   0:f093fec0529b  repo1-0
+
+union repos should use the correct rev number (issue5024)
+
+  $ hg init a
+  $ cd a
+  $ echo a0 >> f
+  $ hg ci -Aqm a0
+  $ cd ..
+  $ hg init b
+  $ cd b
+  $ echo b0 >> f
+  $ hg ci -Aqm b0
+  $ echo b1 >> f
+  $ hg ci -qm b1
+  $ cd ..
+
+"hg files -v" to call fctx.size() -> fctx.iscensored()
+  $ hg files -R union:b+a -r2 -v
+           3   b/f (glob)