add a 'inhibit' extension
authorPierre-Yves David <pierre-yves.david@fb.com>
Fri, 06 Mar 2015 21:25:44 -0800
changeset 1224 859a854cedc3
parent 1223 4e7da688a066
child 1225 577f5340be6f
add a 'inhibit' extension This extension will be used to reduce the scope of evolve in order to make some of its features available to the mass earlier. See extension documentation for details.
hgext/inhibit.py
tests/test-inhibit.t
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hgext/inhibit.py	Fri Mar 06 21:25:44 2015 -0800
@@ -0,0 +1,125 @@
+"""Reduce the changesets evolution feature scope for early and noob friendly UI
+
+The full scale changeset evolution have some massive bleeding edge and it is
+very easy for people not very intimate with the concept to end up in intricate
+situation. In order to get some of the benefit sooner, this extension is
+disabling some of the less polished aspect of evolution. It should gradually
+get thinner and thinner as changeset evolution will get more polished. This
+extension is only recommended for large scale organisations. Individual user
+should probably stick on using Evolution in its current state, understand its
+concept and provide feedback
+
+The first feature provided by this extension is the ability to "inhibit"
+obsolescence markers. Obsolete revision can be cheaply brought back to life
+that way. However as the inhibitor are not fitting in an append only model,
+this is incompatible with sharing mutable history.
+"""
+from mercurial import localrepo
+from mercurial import obsolete
+from mercurial import extensions
+from mercurial import cmdutil
+from mercurial import scmutil
+
+cmdtable = {}
+command = cmdutil.command(cmdtable)
+
+def reposetup(ui, repo):
+
+    class obsinhibitedrepo(repo.__class__):
+
+        @localrepo.storecache('obsinhibit')
+        def _obsinhibit(self):
+            # XXX we should make sure it is invalidated by transaction failure
+            obsinhibit = set()
+            raw = self.sopener.tryread('obsinhibit')
+            for i in xrange(0, len(raw), 20):
+                obsinhibit.add(raw[i:i+20])
+            return obsinhibit
+
+    repo.__class__ = obsinhibitedrepo
+
+# obsolescence inhibitor
+########################
+
+def _schedulewrite(tr, obsinhibit):
+    """Make sure on disk content will be updated on transaction commit"""
+    def writer(fp):
+        """Serialize the inhibited list to disk.
+        """
+        raw = ''.join(obsinhibit)
+        fp.write(raw)
+    tr.addfilegenerator('obsinhibit', ('obsinhibit',), writer)
+    tr.hookargs['obs_inbihited'] = '1'
+
+def _inhibitmarkers(repo, nodes):
+    """add marker inhibitor for all obsolete revision under <nodes>
+
+    Content of <nodes> and all mutable ancestors are considered. Marker for
+    obsolete revision only are created.
+    """
+    newinhibit = repo.set('::%ln and obsolete()', nodes)
+    if newinhibit:
+        tr = repo.transaction('obsinhibit')
+        try:
+            repo._obsinhibit.update(c.node() for c in newinhibit)
+            _schedulewrite(tr, repo._obsinhibit)
+            repo.invalidatevolatilesets()
+            tr.close()
+        finally:
+            tr.release()
+
+def _deinhibitmarkers(repo, nodes):
+    """lift obsolescence inhibition on a set of nodes
+
+    This will be triggered when inhibited nodes received new obsolescence
+    markers. Otherwise the new obsolescence markers would also be inhibited.
+    """
+    deinhibited = repo._obsinhibit & set(nodes)
+    if deinhibited:
+        tr = repo.transaction('obsinhibit')
+        try:
+            repo._obsinhibit -= deinhibited
+            _schedulewrite(tr, repo._obsinhibit)
+            repo.invalidatevolatilesets()
+            tr.close()
+        finally:
+            tr.release()
+
+def _createmarkers(orig, repo, relations, flag=0, date=None, metadata=None):
+    """wrap markers create to make sure we de-inhibit target nodes"""
+    # wrapping transactio to unify the one in each function
+    tr = repo.transaction('add-obsolescence-marker')
+    try:
+        orig(repo, relations, flag, date, metadata)
+        precs = (r[0].node() for r in relations)
+        _deinhibitmarkers(repo, precs)
+        tr.close()
+    finally:
+        tr.release()
+
+def extsetup(ui):
+    # lets wrap the computation of the obsolete set
+    # We apply inhibition there
+    obsfunc = obsolete.cachefuncs['obsolete']
+    def _computeobsoleteset(repo):
+        """remove any inhibited nodes from the obsolete set
+
+        This will trickle down to other part of mercurial (hidden, log, etc)"""
+        obs = obsfunc(repo)
+        getrev = repo.changelog.nodemap.get
+        for n in repo._obsinhibit:
+            obs.discard(getrev(n))
+        return obs
+    obsolete.cachefuncs['obsolete'] = _computeobsoleteset
+    # drop divergence computation since it is incompatible with "light revive"
+    obsolete.cachefuncs['divergent'] = lambda repo: set()
+    # drop bumped computation since it is incompatible with "light revive"
+    obsolete.cachefuncs['bumped'] = lambda repo: set()
+    # wrap create marker to make it able to lift the inhibition
+    extensions.wrapfunction(obsolete, 'createmarkers', _createmarkers)
+
+@command('debugobsinhibit', [], '')
+def cmddebugobsinhibit(ui, repo, *revs):
+    """inhibit obsolescence markers effect on a set of revs"""
+    nodes = (repo[r].node() for r in scmutil.revrange(repo, revs))
+    _inhibitmarkers(repo, nodes)
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/test-inhibit.t	Fri Mar 06 21:25:44 2015 -0800
@@ -0,0 +1,129 @@
+  $ cat >> $HGRCPATH <<EOF
+  > [ui]
+  > logtemplate = {rev}:{node|short} {desc}\n
+  > [extensions]
+  > EOF
+  $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext/evolve.py" >> $HGRCPATH
+  $ echo "inhibit=$(echo $(dirname $TESTDIR))/hgext/inhibit.py" >> $HGRCPATH
+  $ mkcommit() {
+  >    echo "$1" > "$1"
+  >    hg add "$1"
+  >    hg ci -m "add $1"
+  > }
+
+  $ hg init inhibit
+  $ cd inhibit
+  $ mkcommit cA
+  $ mkcommit cB
+  $ mkcommit cC
+  $ mkcommit cD
+  $ hg up 'desc(cA)'
+  0 files updated, 0 files merged, 3 files removed, 0 files unresolved
+  $ mkcommit cE
+  created new head
+  $ mkcommit cG
+  $ mkcommit cH
+  $ mkcommit cJ
+  $ hg log -G 
+  @  7:18214586bf78 add cJ
+  |
+  o  6:cf5c4f4554ce add cH
+  |
+  o  5:5419eb264a33 add cG
+  |
+  o  4:98065434e5c6 add cE
+  |
+  | o  3:2db36d8066ff add cD
+  | |
+  | o  2:7df62a38b9bf add cC
+  | |
+  | o  1:02bcbc3f6e56 add cB
+  |/
+  o  0:54ccbc537fc2 add cA
+  
+
+plain prune
+
+  $ hg prune 1::
+  3 changesets pruned
+  $ hg log -G
+  @  7:18214586bf78 add cJ
+  |
+  o  6:cf5c4f4554ce add cH
+  |
+  o  5:5419eb264a33 add cG
+  |
+  o  4:98065434e5c6 add cE
+  |
+  o  0:54ccbc537fc2 add cA
+  
+  $ hg debugobsinhibit --hidden 1::
+  $ hg log -G
+  @  7:18214586bf78 add cJ
+  |
+  o  6:cf5c4f4554ce add cH
+  |
+  o  5:5419eb264a33 add cG
+  |
+  o  4:98065434e5c6 add cE
+  |
+  | o  3:2db36d8066ff add cD
+  | |
+  | o  2:7df62a38b9bf add cC
+  | |
+  | o  1:02bcbc3f6e56 add cB
+  |/
+  o  0:54ccbc537fc2 add cA
+  
+  $ hg prune --hidden 1::
+  3 changesets pruned
+  $ hg log -G
+  @  7:18214586bf78 add cJ
+  |
+  o  6:cf5c4f4554ce add cH
+  |
+  o  5:5419eb264a33 add cG
+  |
+  o  4:98065434e5c6 add cE
+  |
+  o  0:54ccbc537fc2 add cA
+  
+
+after amend
+
+  $ echo babar > cJ
+  $ hg amend
+  $ hg log -G
+  @  9:55c73a90e4b4 add cJ
+  |
+  o  6:cf5c4f4554ce add cH
+  |
+  o  5:5419eb264a33 add cG
+  |
+  o  4:98065434e5c6 add cE
+  |
+  o  0:54ccbc537fc2 add cA
+  
+  $ hg debugobsinhibit --hidden 18214586bf78
+  $ hg log -G
+  @  9:55c73a90e4b4 add cJ
+  |
+  | o  7:18214586bf78 add cJ
+  |/
+  o  6:cf5c4f4554ce add cH
+  |
+  o  5:5419eb264a33 add cG
+  |
+  o  4:98065434e5c6 add cE
+  |
+  o  0:54ccbc537fc2 add cA
+  
+
+and no divergence
+
+  $ hg summary
+  parent: 9:55c73a90e4b4 tip
+   add cJ
+  branch: default
+  commit: (clean)
+  update: 1 new changesets, 2 branch heads (merge)