keyword: use context manager for rollback locking

hgext/keyword.py

@@ -639,22 +639,21 b' def reposetup(ui, repo):'
             return n
 
         def rollback(self, dryrun=False, force=False):
-            wlock = self.wlock()
-            origrestrict = kwt.restrict
-            try:
-                if not dryrun:
-                    changed = self['.'].files()
-                ret = super(kwrepo, self).rollback(dryrun, force)
-                if not dryrun:
-                    ctx = self['.']
-                    modified, added = _preselect(ctx.status(), changed)
-                    kwt.restrict = False
-                    kwt.overwrite(ctx, modified, True, True)
-                    kwt.overwrite(ctx, added, True, False)
-                return ret
-            finally:
-                kwt.restrict = origrestrict
-                wlock.release()
+            with self.wlock():
+                origrestrict = kwt.restrict
+                try:
+                    if not dryrun:
+                        changed = self['.'].files()
+                    ret = super(kwrepo, self).rollback(dryrun, force)
+                    if not dryrun:
+                        ctx = self['.']
+                        modified, added = _preselect(ctx.status(), changed)
+                        kwt.restrict = False
+                        kwt.overwrite(ctx, modified, True, True)
+                        kwt.overwrite(ctx, added, True, False)
+                    return ret
+                finally:
+                    kwt.restrict = origrestrict
 
     # monkeypatches
     def kwpatchfile_init(orig, self, ui, gp, backend, store, eolmode=None):