largefiles: enable islfilesrepo() prior to a commit (issue3541)

Previously, even if a file was added with --large, 'hg addremove' or 'hg ci -A'
would add all files (including the previously added large files) as normal
files.  Only after a commit where a file was added with --large would subsequent
adds or 'ci -A' take into account the minsize or the pattern configuration.
This change more closely follows the help for largefiles, which mentions that
'add --large' is required to enable the configuration, but doesn't mention the
previously required commit.

Also, if 'hg add --large' was performed and then 'hg forget <file>' (both before
a largefile enabling commit), the forget command would error out saying
'.hglf/<file> not tracked'.  This is also fixed.

This reports that a repo is largefiles enabled as soon as a file is added with
--large, which enables 'add', 'addremove' and 'ci -A' to honor the config
settings before the first commit.  Note that prior to the next commit, if all
largefiles are forgotten, the repository goes back to reporting the repo as not
largefiles enabled.

It makes no sense to handle this by adding a --large option to 'addremove',
because then it would also be needed for 'commit', but only when '-A' is
specified.  While this gets around the awkwardness of having to add a largefile,
then commit it, and then addremove the other files when importing an existing
codebase (and preserving that extra commit in permanent history), it does still
require finding and manually adding one of the files as --large.  Therefore it
is probably desirable to have a --large option for init as well.

hgext/largefiles/lfutil.py

@@ -141,7 +141,7 b' class largefilesdirstate(dirstate.dirsta'
     def normallookup(self, f):
         return super(largefilesdirstate, self).normallookup(unixpath(f))
 
-def openlfdirstate(ui, repo):
+def openlfdirstate(ui, repo, create=True):
     '''
     Return a dirstate object that tracks largefiles: i.e. its root is
     the repo root, but it is saved in .hg/largefiles/dirstate.
@@ -154,7 +154,7 b' def openlfdirstate(ui, repo):'
     # If the largefiles dirstate does not exist, populate and create
     # it. This ensures that we create it on the first meaningful
     # largefiles operation in a new clone.
-    if not os.path.exists(os.path.join(admin, 'dirstate')):
+    if create and not os.path.exists(os.path.join(admin, 'dirstate')):
         util.makedirs(admin)
         matcher = getstandinmatcher(repo)
         for standin in dirstatewalk(repo.dirstate, matcher):
@@ -435,8 +435,11 b' def unixpath(path):'
     return util.pconvert(os.path.normpath(path))
 
 def islfilesrepo(repo):
-    return ('largefiles' in repo.requirements and
-            util.any(shortname + '/' in f[0] for f in repo.store.datafiles()))
+    if ('largefiles' in repo.requirements and
+            util.any(shortname + '/' in f[0] for f in repo.store.datafiles())):
+        return True
+
+    return util.any(openlfdirstate(repo.ui, repo, False))
 
 class storeprotonotcapable(Exception):
     def __init__(self, storetypes):

tests/test-largefiles.t

@@ -1583,3 +1583,40 b' Lock in subrepo, otherwise the change is'
   lf_subrepo_archive/subrepo/normal.txt
 
   $ cd ..
+
+Test that addremove picks up largefiles prior to the initial commit (issue3541)
+
+  $ hg init addrm2
+  $ cd addrm2
+  $ touch large.dat
+  $ touch large2.dat
+  $ touch normal
+  $ hg add --large large.dat
+  $ hg addremove -v
+  adding large2.dat as a largefile
+  adding normal
+
+Test that forgetting all largefiles reverts to islfilesrepo() == False
+(addremove will add *.dat as normal files now)
+  $ hg forget large.dat
+  $ hg forget large2.dat
+  $ hg addremove -v
+  adding large.dat
+  adding large2.dat
+
+Test commit's addremove option prior to the first commit
+  $ hg forget large.dat
+  $ hg forget large2.dat
+  $ hg add --large large.dat
+  $ hg ci -Am "commit"
+  adding large2.dat as a largefile
+  Invoking status precommit hook
+  A large.dat
+  A large2.dat
+  A normal
+  $ find .hglf/ | sort
+  .hglf/
+  .hglf/large.dat
+  .hglf/large2.dat
+
+  $ cd ..