[PATCH evolve-ext-V3] inhibit: direct access with and without warning on a per command basis

[Laurent Charignon]

# HG changeset patch
# User Laurent Charignon <lcharignon at fb.com>
# Date 1431463949 25200
#      Tue May 12 13:52:29 2015 -0700
# Node ID 5abc61cbb35e368185a535444d1d67f3651a7109
# Parent  5e82d78f5872c9503d7b6691c594a13794a9b4a4
inhibit: direct access with and without warning on a per command basis

We introduce a new filtername visibile-directaccess-nowarn to enable direct
access with no warning on a per command basis.
The motivation behing this change is to display warning when attempting direct
access in destructive commands.

diff --git a/hgext/inhibit.py b/hgext/inhibit.py
--- a/hgext/inhibit.py
+++ b/hgext/inhibit.py
@@ -37,6 +37,15 @@
 cmdtable = {}
 command = cmdutil.command(cmdtable)
 
+# List of commands where no warning is shown for direct access
+directaccesslevel = [
+    # warning or not, extension (None if core), command name
+    (False, None, 'update'), 
+    (False, None, 'export'),
+    (True,  'rebase', 'rebase'),
+    (False,  'evolve', 'prune'),
+]
+
 def reposetup(ui, repo):
 
     class obsinhibitedrepo(repo.__class__):
@@ -62,6 +71,20 @@
     repo.__class__ = obsinhibitedrepo
     repo._explicitaccess = set()
 
+def setupdirectaccess():
+    """ Add two new filtername that behave like visible to provide direct access
+    and direct access with warning. Wraps the commands to setup direct access """
+    visiblefilter = repoview.computehidden
+    repoview.filtertable.update({'visible-directaccess-nowarn': visiblefilter})
+    repoview.filtertable.update({'visible-directaccess-warn': visiblefilter})
+    for warn, ext, cmd in directaccesslevel:
+        try:
+            cmdtable = extensions.find(ext).cmdtable if ext else commands.table
+            wrapper = wrapwithwarning if warn else wrapwithoutwarning
+            extensions.wrapcommand(cmdtable, cmd, wrapper)
+        except error.UnknownCommand:
+            # Command not loaded, in that case we don't need to override it
+            pass
 
 def _update(orig, ui, repo, *args, **kwargs):
     """
@@ -192,6 +215,22 @@
     transaction.addpostclose('inhibitposttransaction', inhibitposttransaction)
     return transaction
 
+def wrapwithoutwarning(orig, *args, **kwargs):
+    ui, repo, = args[0], args[1]
+    if repo and repo.filtername == 'visible':
+        object.__setattr__(repo, 'filtername',
+                          'visible-directaccess-nowarn')
+    k = orig(*args, **kwargs)
+    return k
+
+def wrapwithwarning(orig, *args, **kwargs):
+    ui, repo, = args[0], args[1]
+    if repo and repo.filtername == 'visible':
+        object.__setattr__(repo, 'filtername',
+                          'visible-directaccess-warn')
+    k = orig(*args, **kwargs)
+    return k
+
 def extsetup(ui):
     # lets wrap the computation of the obsolete set
     # We apply inhibition there
@@ -214,6 +253,7 @@
     extensions.wrapfunction(obsolete, 'createmarkers', _createmarkers)
     extensions.wrapfunction(repoview, '_getdynamicblockers', _accessvisible)
     extensions.wrapfunction(revset, 'posttreebuilthook', _posttreebuilthook)
+    setupdirectaccess()
     # wrap update to make sure that no obsolete commit is visible after an
     # update
     extensions.wrapcommand(commands.table, 'update', _update)
@@ -250,21 +290,30 @@
     # We extract the symbols that look like hashes and add them to the
     # explicitaccess set
     orig(tree, repo)
-    if repo is not None and repo.filtername == 'visible':
-        prelength = len(repo._explicitaccess)
-        repo.symbols = gethashsymbols(tree)
-        cl = repo.unfiltered().changelog
-        for node in repo.symbols:
-            try:
-                node = cl._partialmatch(node)
-            except error.LookupError:
-                node = None
-            if node is not None:
-                rev = cl.rev(node)
-                if rev not in repo.changelog:
-                    repo._explicitaccess.add(rev)
-        if prelength != len(repo._explicitaccess):
-            repo.invalidatevolatilesets()
+    if repo is not None and repo.filtername:
+        hasdirectaccess = repo.filtername.startswith('visible-directaccess')
+        if hasdirectaccess:
+            prelength = len(repo._explicitaccess)
+            accessbefore = set(repo._explicitaccess)
+            repo.symbols = gethashsymbols(tree)
+            cl = repo.unfiltered().changelog
+            for node in repo.symbols:
+                try:
+                    node = cl._partialmatch(node)
+                except error.LookupError:
+                    node = None
+                if node is not None:
+                    rev = cl.rev(node)
+                    if rev not in repo.changelog:
+                        repo._explicitaccess.add(rev)
+            if prelength != len(repo._explicitaccess):
+                if repo.filtername != 'visible-directaccess-nowarn':
+                    unhiddencommits = repo._explicitaccess - accessbefore
+                    repo.ui.warn( _("Warning: accessing hidden changesets %s " 
+                                    "for write operation\n") % 
+                                    (",".join([str(repo.unfiltered()[l]) 
+                                        for l in unhiddencommits])))
+                repo.invalidatevolatilesets()
 
 @command('debugobsinhibit', [], '')
 def cmddebugobsinhibit(ui, repo, *revs):
diff --git a/tests/test-inhibit.t b/tests/test-inhibit.t
--- a/tests/test-inhibit.t
+++ b/tests/test-inhibit.t
@@ -397,6 +397,9 @@
   (use --hidden to access hidden revisions)
   [255]
   $ hg rebase -r ad78ff7d621f -r 53a94305e133 -d  2db36d8066ff
+  Warning: accessing hidden changesets 2db36d8066ff for write operation
+  Warning: accessing hidden changesets ad78ff7d621f for write operation
+  Warning: accessing hidden changesets 53a94305e133 for write operation
   rebasing 10:ad78ff7d621f "add cK"
   rebasing 11:53a94305e133 "add cL"
   $ hg log -G