fastmanifest: introduce revset of what revision to cache

Summary:
For the moment the revset is just the draft revisions, it will evolve
to include likely rebase destination, branching points etc ...

Test Plan:
We add the result of querying the revset to the test to evaluate how
well the prediction match what is actually being accessed

Reviewers: durham, rmcelroy, ttung

Reviewed By: ttung

Subscribers: mjpieters

Differential Revision: https://phabricator.fb.com/D3115578

Tasks: 10604335

Signature: t1:3115578:1459374926:f9df976aae07db05a44f1fb69a4c83c2a11969dc

fastmanifest.py

@@ -17,6 +17,7 @@ logfile = "" # Filename, is not empty will log access to any manifest
 """
 from mercurial import extensions
 from mercurial import manifest
+from mercurial import revset
 
 
 class manifestaccesslogger(object):
@@ -32,8 +33,18 @@ class manifestaccesslogger(object):
             pass
         return r
 
+def fastmanifesttocache(repo, subset, x):
+    """``fastmanifesttocache(])``
+    Revisions whose fastmanifest should be cached
+
+    For the moment just drafts
+    """
+    return repo.revs("not public()")
+
 def extsetup(ui):
     logfile = ui.config("fastmanifest", "logfile", "")
     if logfile:
         logger = manifestaccesslogger(logfile)
         extensions.wrapfunction(manifest.manifest, 'rev', logger.revwrap)
+    revset.symbols['fastmanifesttocache'] = fastmanifesttocache
+    revset.safesymbols.add('fastmanifesttocache')

tests/test-fastmanifest.t

@@ -14,12 +14,16 @@ Check diagnosis, debugging information
   > }
 
 
-  $ printandclearlog() {
+  $ printaccessedrevs() {
   >     [ ! -f "$TESTTMP/logfile" ] && echo "no access" && return
   >     cat "$TESTTMP/logfile" | sort | uniq
   >     rm "$TESTTMP/logfile"
   > }
 
+  $ printcachedrevs() {
+  > hg log -r "fastmanifesttocache()" -T "{rev}\n"
+  > }
+
   $ mkdir diagnosis
   $ cd diagnosis
   $ hg init
@@ -33,53 +37,83 @@ Check diagnosis, debugging information
 
 1) Commit
 
+  $ printcachedrevs
   $ mkcommit a
-  $ printandclearlog
+  $ printaccessedrevs
   -1
 
+  $ printcachedrevs
+  0
   $ mkcommit b
-  $ printandclearlog
+  $ printaccessedrevs
   -1
   0
 
   $ echo "c" > a
+  $ printcachedrevs
+  0
+  1
   $ hg commit -m "new a"
-  $ printandclearlog
+  $ printaccessedrevs
   -1
   1
 
 2) Diff
 
+  $ printcachedrevs
+  0
+  1
+  2
   $ hg diff -c . > /dev/null
-  $ printandclearlog
+  $ printaccessedrevs
   1
   2
 
+  $ printcachedrevs
+  0
+  1
+  2
   $ hg diff -c ".^" > /dev/null
-  $ printandclearlog
+  $ printaccessedrevs
   0
   1
 
+  $ printcachedrevs
+  0
+  1
+  2
   $ hg diff -r ".^" > /dev/null
-  $ printandclearlog
+  $ printaccessedrevs
   1
   2
 
 3) Log
 
+  $ printcachedrevs
+  0
+  1
+  2
   $ hg log a > /dev/null
-  $ printandclearlog
+  $ printaccessedrevs
   no access
 
 4) Update
 
+  $ printcachedrevs
+  0
+  1
+  2
   $ hg update ".^^" -q
-  $ printandclearlog
+  $ printaccessedrevs
   0
   2
 
+  $ printcachedrevs
+  0
+  1
+  2
   $ hg update tip -q
-  $ printandclearlog
+  $ printaccessedrevs
   0
   2
 
@@ -106,7 +140,7 @@ Check diagnosis, debugging information
   o  0 1f0dee641bb7258c56bd60e93edfa2405381c41e add a
   
 
-  $ printandclearlog
+  $ printaccessedrevs
   -1
   2
   3
@@ -116,7 +150,7 @@ Check diagnosis, debugging information
   rebasing 5:5234b99c4f1d "add e"
   rebasing 6:dd82c74514cb "add f" (tip)
   saved backup bundle to $TESTTMP/diagnosis/.hg/strip-backup/5234b99c4f1d-c2e049ad-backup.hg (glob)
-  $ printandclearlog
+  $ printaccessedrevs
   -1
   2
   4