# HG changeset patch
# User Peter Arrenbrecht <peter.arrenbrecht@gmail.com>
# Date 2011-03-12 17:29:02
# Node ID 395a84f78736aa1912d16ae2138e7d5596bdaa42
# Parent  54b198fe9768fc236bedc7db3e5fbf0b48df332b

httprepo: use caps instead of between for compat check

We usually query the capabilities at some point anyway so this way the first roundtrip
actually does useful work.

diff --git a/mercurial/httprepo.py b/mercurial/httprepo.py
--- a/mercurial/httprepo.py
+++ b/mercurial/httprepo.py
@@ -52,10 +52,13 @@ class httprepository(wireproto.wirerepos
 
     # look up capabilities only when needed
 
+    def _fetchcaps(self):
+        self.caps = set(self._call('capabilities').split())
+
     def get_caps(self):
         if self.caps is None:
             try:
-                self.caps = set(self._call('capabilities').split())
+                self._fetchcaps()
             except error.RepoError:
                 self.caps = set()
             self.ui.debug('capabilities: %s\n' %
@@ -195,7 +198,13 @@ def instance(ui, path, create):
             inst = httpsrepository(ui, path)
         else:
             inst = httprepository(ui, path)
-        inst.between([(nullid, nullid)])
+        try:
+            # Try to do useful work when checking compatibility.
+            # Usually saves a roundtrip since we want the caps anyway.
+            inst._fetchcaps()
+        except error.RepoError:
+            # No luck, try older compatibility check.
+            inst.between([(nullid, nullid)])
         return inst
     except error.RepoError:
         ui.note('(falling back to static-http)\n')
diff --git a/tests/test-http-proxy.t b/tests/test-http-proxy.t
--- a/tests/test-http-proxy.t
+++ b/tests/test-http-proxy.t
@@ -98,27 +98,22 @@ do not use the proxy if it is in the no 
   updating to branch default
   1 files updated, 0 files merged, 0 files removed, 0 files unresolved
   $ cat proxy.log
-  * - - [*] "GET http://localhost:$HGPORT/?cmd=between&pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000 HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=capabilities HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=stream_out HTTP/1.1" - - (glob)
-  * - - [*] "GET http://localhost:$HGPORT/?cmd=between&pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000 HTTP/1.1" - - (glob)
+  * - - [*] "GET http://localhost:$HGPORT/?cmd=capabilities HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=heads HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=changegroup&roots=0000000000000000000000000000000000000000 HTTP/1.1" - - (glob)
+  * - - [*] "GET http://localhost:$HGPORT/?cmd=listkeys&namespace=bookmarks HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=capabilities HTTP/1.1" - - (glob)
-  * - - [*] "GET http://localhost:$HGPORT/?cmd=listkeys&namespace=bookmarks HTTP/1.1" - - (glob)
-  * - - [*] "GET http://localhost:$HGPORT/?cmd=between&pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000 HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=heads HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=changegroup&roots=0000000000000000000000000000000000000000 HTTP/1.1" - - (glob)
+  * - - [*] "GET http://localhost:$HGPORT/?cmd=listkeys&namespace=bookmarks HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=capabilities HTTP/1.1" - - (glob)
-  * - - [*] "GET http://localhost:$HGPORT/?cmd=listkeys&namespace=bookmarks HTTP/1.1" - - (glob)
-  * - - [*] "GET http://localhost:$HGPORT/?cmd=between&pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000 HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=heads HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=changegroup&roots=0000000000000000000000000000000000000000 HTTP/1.1" - - (glob)
+  * - - [*] "GET http://localhost:$HGPORT/?cmd=listkeys&namespace=bookmarks HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=capabilities HTTP/1.1" - - (glob)
-  * - - [*] "GET http://localhost:$HGPORT/?cmd=listkeys&namespace=bookmarks HTTP/1.1" - - (glob)
-  * - - [*] "GET http://localhost:$HGPORT/?cmd=between&pairs=0000000000000000000000000000000000000000-0000000000000000000000000000000000000000 HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=heads HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=changegroup&roots=0000000000000000000000000000000000000000 HTTP/1.1" - - (glob)
-  * - - [*] "GET http://localhost:$HGPORT/?cmd=capabilities HTTP/1.1" - - (glob)
   * - - [*] "GET http://localhost:$HGPORT/?cmd=listkeys&namespace=bookmarks HTTP/1.1" - - (glob)
 
diff --git a/tests/test-schemes.t b/tests/test-schemes.t
--- a/tests/test-schemes.t
+++ b/tests/test-schemes.t
@@ -25,7 +25,7 @@ check that {1} syntax works
 
   $ hg incoming --debug parts://localhost
   using http://localhost:$HGPORT/
-  sending between command
+  sending capabilities command
   comparing with parts://localhost
   sending heads command
   searching for changes