From 94e57bcc9dcd5fb26675eaebbb8b65797200df3d Mon Sep 17 00:00:00 2001
From: Thomas Leonard <talex5@gmail.com>
Date: Sun, 25 Mar 2012 10:49:59 +0100
Subject: [PATCH] Warn about replaced interfaces in "0install update"

---
 0alias                        | 11 ++++++++---
 zeroinstall/cmd/update.py     |  6 ++++++
 zeroinstall/injector/model.py |  2 +-
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/0alias b/0alias
index 422ff6c..681fa3d 100755
--- a/0alias
+++ b/0alias
@@ -236,10 +236,15 @@ except model.SafeException as ex:
 	print(ex, file=sys.stderr)
 	sys.exit(1)
 
-feed = config.iface_cache.get_feed(interface_uri)
-replacement_uri = feed.get_replaced_by()
-if replacement_uri is not None:
+seen = set([interface_uri])
+while True:
+	feed = config.iface_cache.get_feed(interface_uri)
+	replacement_uri = feed.get_replaced_by()
+	if replacement_uri is None:
+		break
 	print(_("(interface {old} has been replaced by {new}; using that instead)").format(old = interface_uri, new = replacement_uri))
+	assert replacement_uri not in seen, "loop detected!"
+	seen.add(replacement_uri)
 	interface_uri = replacement_uri
 
 wrapper = open(script, 'w')
diff --git a/zeroinstall/cmd/update.py b/zeroinstall/cmd/update.py
index 0da0be6..c4cc4a8 100644
--- a/zeroinstall/cmd/update.py
+++ b/zeroinstall/cmd/update.py
@@ -83,3 +83,9 @@ def handle(config, options, args):
 	else:
 		if not changes:
 			print(_("No updates found. Continuing with version {version}.").format(version = root_sel.version))
+
+	root_feed = config.iface_cache.get_feed(iface_uri)
+	if root_feed:
+		target = root_feed.get_replaced_by()
+		if target is not None:
+			print(_("Warning: interface {old} has been replaced by {new}".format(old = iface_uri, new = target)))
diff --git a/zeroinstall/injector/model.py b/zeroinstall/injector/model.py
index 0a120a0..77f633f 100644
--- a/zeroinstall/injector/model.py
+++ b/zeroinstall/injector/model.py
@@ -1179,7 +1179,7 @@ class ZeroInstallFeed(object):
 		for child in self.metadata:
 			if child.uri == XMLNS_IFACE and child.name == 'replaced-by':
 				new_uri = child.getAttribute('interface')
-				if new_uri:
+				if new_uri and (new_uri.startswith('http:') or new_uri.startswith('https:') or self.local_path):
 					return new_uri
 		return None
 
-- 
2.11.4.GIT