changeset 35963:efbd04238029

cmdutil: convert _revertprefetch() to a generic stored file hook (API) This will be used by LFS to fetch required files in a group for multiple commands, prior to being accessed. That avoids the one-at-a-time fetch when the filelog wrapper goes to access it, and it is missing locally (which costs two round trips to the server.) The core command list that needs this is probably at least: - annotate - archive (which is also used by extdiff) - cat - diff - export - grep - verify (sadly) - anything that has the '{data}' template There are no core users of the revert prefetch hook, and never have been since it was introduced in 45e02cfad4bd for remotefilelog. Thanks to Yuya for figuring out a way to reliably trigger the deprecated warning. Unfortunately, it wanted to blame the caller of revert. Passing along an adjusted stack level seemed the least bad choice (although it still blames a core function). One thing to note is that the store lock isn't being held when this is called. I'm not at all familiar with remotefilelog or its locking requirements, so this may not be a big deal. Currently, LFS doesn't hold a lock when downloading files. Even though largefiles doesn't either, I'm starting to think it should, and maybe the .hg/store/lock isn't good enough to cover the globally shared cache. .. api:: The cmdutil._revertprefetch() hook point for prefetching stored files has been replaced by the command agnostic cmdutil._prefetchfiles(). The new function takes a list of files, instead of a list of lists of files.
author Matt Harbison <matt_harbison@yahoo.com>
date Sun, 04 Feb 2018 14:14:28 -0500
parents 0b79f99fd7b0
children d857cad588e4
files mercurial/cmdutil.py mercurial/ui.py
diffstat 2 files changed, 19 insertions(+), 5 deletions(-) [+]
line wrap: on
line diff
--- a/mercurial/cmdutil.py	Sat Feb 03 21:26:12 2018 -0500
+++ b/mercurial/cmdutil.py	Sun Feb 04 14:14:28 2018 -0500
@@ -2862,7 +2862,14 @@
 
         if not opts.get('dry_run'):
             needdata = ('revert', 'add', 'undelete')
-            _revertprefetch(repo, ctx, *[actions[name][0] for name in needdata])
+            if _revertprefetch is not _revertprefetchstub:
+                ui.deprecwarn("'cmdutil._revertprefetch' is deprecated, use "
+                              "'cmdutil._prefetchfiles'", '4.6', stacklevel=1)
+                _revertprefetch(repo, ctx,
+                                *[actions[name][0] for name in needdata])
+            oplist = [actions[name][0] for name in needdata]
+            _prefetchfiles(repo, ctx,
+                           [f for sublist in oplist for f in sublist])
             _performrevert(repo, parents, ctx, actions, interactive, tobackup)
 
         if targetsubs:
@@ -2875,8 +2882,15 @@
                     raise error.Abort("subrepository '%s' does not exist in %s!"
                                       % (sub, short(ctx.node())))
 
-def _revertprefetch(repo, ctx, *files):
-    """Let extension changing the storage layer prefetch content"""
+def _revertprefetchstub(repo, ctx, *files):
+    """Stub method for detecting extension wrapping of _revertprefetch(), to
+    issue a deprecation warning."""
+
+_revertprefetch = _revertprefetchstub
+
+def _prefetchfiles(repo, ctx, files):
+    """Let extensions changing the storage layer prefetch content for any non
+    merge based command."""
 
 def _performrevert(repo, parents, ctx, actions, interactive=False,
                    tobackup=None):
--- a/mercurial/ui.py	Sat Feb 03 21:26:12 2018 -0500
+++ b/mercurial/ui.py	Sun Feb 04 14:14:28 2018 -0500
@@ -1614,7 +1614,7 @@
                      msg, *calframe[stacklevel][1:4])
             curframe = calframe = None  # avoid cycles
 
-    def deprecwarn(self, msg, version):
+    def deprecwarn(self, msg, version, stacklevel=2):
         """issue a deprecation warning
 
         - msg: message explaining what is deprecated and how to upgrade,
@@ -1625,7 +1625,7 @@
             return
         msg += ("\n(compatibility will be dropped after Mercurial-%s,"
                 " update your code.)") % version
-        self.develwarn(msg, stacklevel=2, config='deprec-warn')
+        self.develwarn(msg, stacklevel=stacklevel, config='deprec-warn')
 
     def exportableenviron(self):
         """The environment variables that are safe to export, e.g. through