upgrade: introduce the internal code for revlog cloning selection

For now we still clone every single revlogs but all the selection mechanism is
now in place in the lower layer.

The next changesets will introduce the user interface part of the selection.

mercurial/upgrade.py

@@ -562,7 +562,26 b' def _copyrevlog(tr, destrepo, oldrl, une'
             or unencodedname.endswith('00manifest.i')):
         destrepo.svfs.fncache.add(unencodedname)
 
-def _clonerevlogs(ui, srcrepo, dstrepo, tr, deltareuse, forcedeltabothparents):
+UPGRADE_CHANGELOG = object()
+UPGRADE_MANIFEST = object()
+UPGRADE_FILELOG = object()
+
+UPGRADE_ALL_REVLOGS = frozenset([UPGRADE_CHANGELOG,
+                                 UPGRADE_MANIFEST,
+                                 UPGRADE_FILELOG])
+
+def matchrevlog(revlogfilter, entry):
+    """check is a revlog is selected for cloning
+
+    The store entry is checked against the passed filter"""
+    if entry.endswith('00changelog.i'):
+        return UPGRADE_CHANGELOG in revlogfilter
+    elif entry.endswith('00manifest.i'):
+        return UPGRADE_MANIFEST in revlogfilter
+    return UPGRADE_FILELOG in revlogfilter
+
+def _clonerevlogs(ui, srcrepo, dstrepo, tr, deltareuse, forcedeltabothparents,
+                  revlogs=UPGRADE_ALL_REVLOGS):
     """Copy revlogs between 2 repos."""
     revcount = 0
     srcsize = 0
@@ -643,7 +662,6 b' def _clonerevlogs(ui, srcrepo, dstrepo, '
             continue
 
         oldrl = _revlogfrompath(srcrepo, unencoded)
-        newrl = _revlogfrompath(dstrepo, unencoded)
 
         if isinstance(oldrl, changelog.changelog) and 'c' not in seen:
             ui.write(_('finished migrating %d manifest revisions across %d '
@@ -682,11 +700,19 b' def _clonerevlogs(ui, srcrepo, dstrepo, '
             progress = srcrepo.ui.makeprogress(_('file revisions'),
                                                total=frevcount)
 
+        if matchrevlog(revlogs, unencoded):
+            ui.note(_('cloning %d revisions from %s\n')
+                    % (len(oldrl), unencoded))
+            newrl = _revlogfrompath(dstrepo, unencoded)
+            oldrl.clone(tr, newrl, addrevisioncb=oncopiedrevision,
+                        deltareuse=deltareuse,
+                        forcedeltabothparents=forcedeltabothparents)
+        else:
+            msg = _('blindly copying %s containing %i revisions\n')
+            ui.note(msg % (unencoded, len(oldrl)))
+            _copyrevlog(tr, dstrepo, oldrl, unencoded)
 
-        ui.note(_('cloning %d revisions from %s\n') % (len(oldrl), unencoded))
-        oldrl.clone(tr, newrl, addrevisioncb=oncopiedrevision,
-                    deltareuse=deltareuse,
-                    forcedeltabothparents=forcedeltabothparents)
+            newrl = _revlogfrompath(dstrepo, unencoded)
 
         info = newrl.storageinfo(storedsize=True)
         datasize = info['storedsize'] or 0
@@ -746,7 +772,8 b' def _finishdatamigration(ui, srcrepo, ds'
     before the new store is swapped into the original location.
     """
 
-def _upgraderepo(ui, srcrepo, dstrepo, requirements, actions):
+def _upgraderepo(ui, srcrepo, dstrepo, requirements, actions,
+                 revlogs=UPGRADE_ALL_REVLOGS):
     """Do the low-level work of upgrading a repository.
 
     The upgrade is effectively performed as a copy between a source
@@ -775,7 +802,7 b' def _upgraderepo(ui, srcrepo, dstrepo, r'
 
     with dstrepo.transaction('upgrade') as tr:
         _clonerevlogs(ui, srcrepo, dstrepo, tr, deltareuse,
-                     're-delta-multibase' in actions)
+                      're-delta-multibase' in actions, revlogs=revlogs)
 
     # Now copy other files in the store directory.
     # The sorted() makes execution deterministic.