More changes to rules and chains.

Now a link has a rule, action, chain, and function, not all of which needs to
be specified.  The action is a LinkAction enum adn specifies what to do should
the rule match.  The use of the chain or function depends on what the action
is.

Several interface changes now make it easier to jump to other chains, push
(i.e. detour) to chains, etc.  Rules can also now specify that they should not
be recorded in X-* headers.

Added a TruthRule which always matches.

2 files changed, 6 insertions, 8 deletions

diff --git a/Mailman/rules/docs/emergency.txt b/Mailman/rules/docs/emergency.txt
index 685d7bcb6..1375c3bc9 100644
--- a/Mailman/rules/docs/emergency.txt
+++ b/Mailman/rules/docs/emergency.txt
@@ -16,15 +16,12 @@ list are held for moderator approval.
     ... An important message.
     ... """)
 
-The emergency rule is matched as part of the built-in chain.
-
-    >>> from Mailman.configuration import config
-    >>> chain = config.chains['built-in']
-
-The emergency rule matches if the flag is set on the mailing list.
+The emergency rule is matched as part of the built-in chain.  The emergency
+rule matches if the flag is set on the mailing list.
 
+    >>> from Mailman.app.chains import process
     >>> mlist.emergency = True
-    >>> chain.process(mlist, msg, {})
+    >>> process('built-in', mlist, msg, {})
 
 There are two messages in the virgin queue.  The one addressed to the original
 sender will contain a token we can use to grab the held message out of the
@@ -72,6 +69,6 @@ However, if the message metadata has a 'moderator_approved' key set, then even
 if the mailing list has its emergency flag set, the message still goes through
 to the membership.
 
-    >>> chain.process(mlist, msg, dict(moderator_approved=True))
+    >>> process('built-in', mlist, msg, dict(moderator_approved=True))
     >>> len(virginq.files)
     0
diff --git a/Mailman/rules/docs/rules.txt b/Mailman/rules/docs/rules.txt
index 1f5b147e7..d2d291331 100644
--- a/Mailman/rules/docs/rules.txt
+++ b/Mailman/rules/docs/rules.txt
@@ -31,6 +31,7 @@ names to rule objects.
     no-subject True
     non-member True
     suspicious-header True
+    truth True
 
 You can get a rule by name.