Mercurial > public > mercurial-scm > hg-stable
diff mercurial/cmdutil.py @ 42494:561cd02c58ff
cat: don't prefetch files unless the output requires it
It's a waste to cache lfs blobs when cat'ing the raw data at best, but a hassle
debugging when the blob is missing. I'm not sure if there are other commands
that have '{data}' for output, and if there's a general way to prefetch on that
keyword.
It's interesting that the verbose output seems to leak into the JSON output, but
that seems like an existing bug.
| author | Matt Harbison <matt_harbison@yahoo.com> |
|---|---|
| date | Thu, 04 Oct 2018 00:57:11 -0400 |
| parents | 307f67d4aee3 |
| children | 5f2f6912c9e6 |
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--- a/mercurial/cmdutil.py Wed Jun 12 19:01:49 2019 -0400 +++ b/mercurial/cmdutil.py Thu Oct 04 00:57:11 2018 -0400 @@ -2353,14 +2353,22 @@ return ret +def _catfmtneedsdata(fm): + return not fm.datahint() or 'data' in fm.datahint() + def _updatecatformatter(fm, ctx, matcher, path, decode): """Hook for adding data to the formatter used by ``hg cat``. Extensions (e.g., lfs) can wrap this to inject keywords/data, but must call this method first.""" - data = ctx[path].data() - if decode: - data = ctx.repo().wwritedata(path, data) + + # data() can be expensive to fetch (e.g. lfs), so don't fetch it if it + # wasn't requested. + data = b'' + if _catfmtneedsdata(fm): + data = ctx[path].data() + if decode: + data = ctx.repo().wwritedata(path, data) fm.startitem() fm.context(ctx=ctx) fm.write('data', '%s', data) @@ -2391,13 +2399,15 @@ mfnode = ctx.manifestnode() try: if mfnode and mfl[mfnode].find(file)[0]: - scmutil.prefetchfiles(repo, [ctx.rev()], matcher) + if _catfmtneedsdata(basefm): + scmutil.prefetchfiles(repo, [ctx.rev()], matcher) write(file) return 0 except KeyError: pass - scmutil.prefetchfiles(repo, [ctx.rev()], matcher) + if _catfmtneedsdata(basefm): + scmutil.prefetchfiles(repo, [ctx.rev()], matcher) for abs in ctx.walk(matcher): write(abs)