mercurial/wireproto.py

--- a/mercurial/wireproto.py	Mon Aug 03 06:13:05 2015 -0700
+++ b/mercurial/wireproto.py	Wed Aug 05 14:51:34 2015 -0400
@@ -58,48 +58,12 @@
         Some protocols may have compressed the contents."""
         raise NotImplementedError()
 
-# abstract batching support
-
-class future(object):
-    '''placeholder for a value to be set later'''
-    def set(self, value):
-        if util.safehasattr(self, 'value'):
-            raise error.RepoError("future is already set")
-        self.value = value
-
-class batcher(object):
-    '''base class for batches of commands submittable in a single request
-
-    All methods invoked on instances of this class are simply queued and
-    return a a future for the result. Once you call submit(), all the queued
-    calls are performed and the results set in their respective futures.
-    '''
-    def __init__(self):
-        self.calls = []
-    def __getattr__(self, name):
-        def call(*args, **opts):
-            resref = future()
-            self.calls.append((name, args, opts, resref,))
-            return resref
-        return call
-    def submit(self):
-        pass
-
-class localbatch(batcher):
-    '''performs the queued calls directly'''
-    def __init__(self, local):
-        batcher.__init__(self)
-        self.local = local
-    def submit(self):
-        for name, args, opts, resref in self.calls:
-            resref.set(getattr(self.local, name)(*args, **opts))
-
-class remotebatch(batcher):
+class remotebatch(peer.batcher):
     '''batches the queued calls; uses as few roundtrips as possible'''
     def __init__(self, remote):
         '''remote must support _submitbatch(encbatch) and
         _submitone(op, encargs)'''
-        batcher.__init__(self)
+        peer.batcher.__init__(self)
         self.remote = remote
     def submit(self):
         req, rsp = [], []
@@ -128,41 +92,10 @@
             encresref.set(encres)
             resref.set(batchable.next())
 
-def batchable(f):
-    '''annotation for batchable methods
-
-    Such methods must implement a coroutine as follows:
-
-    @batchable
-    def sample(self, one, two=None):
-        # Handle locally computable results first:
-        if not one:
-            yield "a local result", None
-        # Build list of encoded arguments suitable for your wire protocol:
-        encargs = [('one', encode(one),), ('two', encode(two),)]
-        # Create future for injection of encoded result:
-        encresref = future()
-        # Return encoded arguments and future:
-        yield encargs, encresref
-        # Assuming the future to be filled with the result from the batched
-        # request now. Decode it:
-        yield decode(encresref.value)
-
-    The decorator returns a function which wraps this coroutine as a plain
-    method, but adds the original method as an attribute called "batchable",
-    which is used by remotebatch to split the call into separate encoding and
-    decoding phases.
-    '''
-    def plain(*args, **opts):
-        batchable = f(*args, **opts)
-        encargsorres, encresref = batchable.next()
-        if not encresref:
-            return encargsorres # a local result in this case
-        self = args[0]
-        encresref.set(self._submitone(f.func_name, encargsorres))
-        return batchable.next()
-    setattr(plain, 'batchable', f)
-    return plain
+# Forward a couple of names from peer to make wireproto interactions
+# slightly more sensible.
+batchable = peer.batchable
+future = peer.future
 
 # list of nodes encoding / decoding