--- a/hgext/pushlog-legacy/tests/helpers.sh
+++ b/hgext/pushlog-legacy/tests/helpers.sh
@@ -17,8 +17,13 @@ pretxnchangegroup.pushlog = python:mozhg
 EOF
 }
 
 alias http=$TESTDIR/testing/http-request.py
 
 jsoncompare() {
   python $TESTDIR/hgext/pushlog-legacy/tests/json-compare.py $1 $2
 }
+
+httpjson() {
+  http --body-file body --no-headers $1
+  python -m json.tool < body
+}

new file mode 100644
--- /dev/null
+++ b/hgext/pushlog-legacy/tests/test-obsolescence.t
@@ -0,0 +1,208 @@
+  $ . $TESTDIR/hgext/pushlog-legacy/tests/helpers.sh
+
+  $ cat >> $HGRCPATH << EOF
+  > [experimental]
+  > evolution = all
+  > [extensions]
+  > rebase =
+  > EOF
+
+  $ hg init server
+  $ cd server
+  $ cat >> .hg/hgrc << EOF
+  > [extensions]
+  > pushlog = $TESTDIR/hgext/pushlog
+  > pushlog-feed = $TESTDIR/hgext/pushlog-legacy/pushlog-feed.py
+  > [phases]
+  > publish = false
+  > [web]
+  > templates = $TESTDIR/hgtemplates
+  > style = gitweb_mozilla
+  > EOF
+
+  $ hg serve -d -p $HGPORT --pid-file hg.pid -A access.log -E error.log
+  $ cat hg.pid >> $DAEMON_PIDS
+  $ cd ..
+
+  $ export USER=user@example.com
+
+  $ hg -q clone --pull server client
+  $ cd client
+  $ touch foo
+  $ hg -q commit -A -m initial
+  $ hg -q push
+  recorded push in pushlog
+  $ touch file0
+  $ hg -q commit -A -m file0
+  $ touch file1
+  $ hg -q commit -A -m file1
+  $ hg -q push
+  recorded push in pushlog
+  $ hg -q up -r 0
+  $ touch file2
+  $ hg -q commit -A -m file2
+  $ touch file3
+  $ hg -q commit -A -m file3
+  $ hg push -f
+  pushing to $TESTTMP/server
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 2 files (+1 heads)
+  recorded push in pushlog
+
+  $ hg rebase -s ae13d9da6966 -d 62eebb2f0f00
+  rebasing 1:ae13d9da6966 "file0"
+  rebasing 2:d313a202a85e "file1"
+  $ hg push
+  pushing to $TESTTMP/server
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 0 changes to 2 files
+  recorded push in pushlog
+  2 new obsolescence markers
+
+FIXME Hidden changesets should not be exposed to version 1
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?version=1"
+  200
+  {
+      "1": {
+          "changesets": [
+              "96ee1d7354c4ad7372047672c36a1f561e3a6a4c"
+          ],
+          "date": \d+, (re)
+          "user": "user@example.com"
+      },
+      "2": {
+          "changesets": [
+              "ae13d9da6966307c98b60987fb4fedc2e2f29736",
+              "d313a202a85e114000f669c2fcb49ad42376ac04"
+          ],
+          "date": \d+, (re)
+          "user": "user@example.com"
+      },
+      "3": {
+          "changesets": [
+              "b3641753ee63b166fad7c5f10060b0cbbc8a86b0",
+              "62eebb2f0f00195f9d965f718090c678c4fa414d"
+          ],
+          "date": \d+, (re)
+          "user": "user@example.com"
+      },
+      "4": {
+          "changesets": [
+              "418a63f508062fb2eb9130065c5ddc7908dd5949",
+              "d129109168f0ed985e51b0f86df256acdcfcfe45"
+          ],
+          "date": \d+, (re)
+          "user": "user@example.com"
+      }
+  }
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?version=1&full=1"
+  404
+  "hidden revision 'd313a202a85e114000f669c2fcb49ad42376ac04'"
+
+FIXME Hidden changesets should not be exposed to version 2
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?version=2"
+  200
+  {
+      "lastpushid": 4,
+      "pushes": {
+          "1": {
+              "changesets": [
+                  "96ee1d7354c4ad7372047672c36a1f561e3a6a4c"
+              ],
+              "date": \d+, (re)
+              "user": "user@example.com"
+          },
+          "2": {
+              "changesets": [
+                  "ae13d9da6966307c98b60987fb4fedc2e2f29736",
+                  "d313a202a85e114000f669c2fcb49ad42376ac04"
+              ],
+              "date": \d+, (re)
+              "user": "user@example.com"
+          },
+          "3": {
+              "changesets": [
+                  "b3641753ee63b166fad7c5f10060b0cbbc8a86b0",
+                  "62eebb2f0f00195f9d965f718090c678c4fa414d"
+              ],
+              "date": \d+, (re)
+              "user": "user@example.com"
+          },
+          "4": {
+              "changesets": [
+                  "418a63f508062fb2eb9130065c5ddc7908dd5949",
+                  "d129109168f0ed985e51b0f86df256acdcfcfe45"
+              ],
+              "date": \d+, (re)
+              "user": "user@example.com"
+          }
+      }
+  }
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?version=2&full=1"
+  404
+  "hidden revision 'd313a202a85e114000f669c2fcb49ad42376ac04'"
+
+FIXME Hidden changesets handled properly on feed
+
+  $ http --no-headers "http://localhost:$HGPORT/atom-pushlog"
+  404
+  
+  <?xml version="1.0" encoding="ascii"?>
+  <feed xmlns="http://www.w3.org/2005/Atom">
+   <!-- Error -->
+   <id>http://*:$HGPORT/</id> (glob)
+   <link rel="self" href="http://*:$HGPORT/atom-log"/> (glob)
+   <link rel="alternate" href="http://*:$HGPORT/"/> (glob)
+   <title>Error</title>
+   <updated>1970-01-01T00:00:00+00:00</updated>
+   <entry>
+    <title>Error</title>
+    <id>https://mercurial-scm.org/#error</id>
+    <author>
+      <name>mercurial</name>
+    </author>
+    <updated>1970-01-01T00:00:00+00:00</updated>
+    <content type="text">hidden revision 'd313a202a85e114000f669c2fcb49ad42376ac04'</content>
+   </entry>
+  </feed>
+  
+
+FIXME Specifying a fromchange with a hidden changeset works
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?fromchange=d313a202a85e"
+  404
+  "hidden revision 'd313a202a85e'"
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?fromchange=d313a202a85e&full=1"
+  404
+  "hidden revision 'd313a202a85e'"
+
+FIXME Specifying a tochange with a hidden changeset works
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?startID=1&tochange=ae13d9da6966"
+  404
+  "hidden revision 'ae13d9da6966'"
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?startID=1&tochange=ae13d9da6966&full=1"
+  404
+  "hidden revision 'ae13d9da6966'"
+
+FIXME Specifying a hidden changeset works
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?changeset=ae13d9da6966"
+  404
+  "hidden revision 'ae13d9da6966'"
+
+  $ httpjson "http://localhost:$HGPORT/json-pushes?changeset=ae13d9da6966&full=1"
+  404
+  "hidden revision 'ae13d9da6966'"