# HG changeset patch
# User Brendan Cully <brendan@kublai.com>
# Date 1184087184 25200
# Node ID a49f2a4d5ff73dfde8e4d18a0f59f7f63c801504
# Parent  8d9bdcbb2b1852d2507cbb7e5d922f549f73f19d
archive: abort on empty repository. Fixes #624.

diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -133,7 +133,10 @@ def archive(ui, repo, dest, **opts):
     The default is the basename of the archive, with suffixes removed.
     '''
 
-    node = repo.changectx(opts['rev']).node()
+    ctx = repo.changectx(opts['rev'])
+    if not ctx:
+        raise util.Abort(_('repository has no revisions'))
+    node = ctx.node()
     dest = cmdutil.make_filename(repo, dest, node)
     if os.path.realpath(dest) == repo.root:
         raise util.Abort(_('repository root cannot be destination'))
diff --git a/tests/test-archive b/tests/test-archive
--- a/tests/test-archive
+++ b/tests/test-archive
@@ -67,3 +67,9 @@ hg archive -r 0 -t tar rev-%r.tar
 if [ -f rev-0.tar ]; then
     echo 'rev-0.tar created'
 fi
+
+echo '% empty repo'
+hg init ../empty
+cd ../empty
+hg archive ../test-empty
+exit 0
diff --git a/tests/test-archive.out b/tests/test-archive.out
--- a/tests/test-archive.out
+++ b/tests/test-archive.out
@@ -39,3 +39,5 @@ test-TIP/bar
 test-TIP/baz/bletch
 test-TIP/foo
 rev-0.tar created
+% empty repo
+abort: repository has no revisions