archive: add branch and tag informations to the .hg_archival.txt file

Up to this changeset, only the repo (first node) and current node hash were
included. This adds also the named branch and tags.

So the additional lines to .hg_archival.txt are
branch: the named branch
tag: the global tags of this revision, one per line in case of multiple tags
latesttag: if the revision is untagged, the latest tag (most recent in
           ancestors), again one per line if this ancestor has multiple tags.
latestagdistance: the longest distance (changesets) to this latest ancestor.

mercurial/archival.py

@@ -7,6 +7,7 b''
 
 from i18n import _
 from node import hex
+import cmdutil
 import util
 import cStringIO, os, stat, tarfile, time, zipfile
 import zlib, gzip
@@ -217,9 +218,25 b' def archive(repo, dest, node, kind, deco'
     archiver = archivers[kind](dest, prefix, mtime or ctx.date()[0])
 
     if repo.ui.configbool("ui", "archivemeta", True):
-        write('.hg_archival.txt', 0644, False,
-              lambda: 'repo: %s\nnode: %s\n' % (
-                  hex(repo.changelog.node(0)), hex(node)))
+        def metadata():
+            base = 'repo: %s\nnode: %s\nbranch: %s\n' % (
+                hex(repo.changelog.node(0)), hex(node), ctx.branch())
+
+            tags = ''.join('tag: %s\n' % t for t in ctx.tags()
+                           if repo.tagtype(t) == 'global')
+            if not tags:
+                repo.ui.pushbuffer()
+                opts = {'template': '{latesttag}\n{latesttagdistance}',
+                        'style': '', 'patch': None, 'git': None}
+                cmdutil.show_changeset(repo.ui, repo, opts).show(ctx)
+                ltags, dist = repo.ui.popbuffer().split('\n')
+                tags = ''.join('latesttag: %s\n' % t for t in ltags.split(':'))
+                tags += 'latesttagdistance: %s\n' % dist
+
+            return base + tags
+
+        write('.hg_archival.txt', 0644, False, metadata)
+
     for f in ctx:
         ff = ctx.flags(f)
         write(f, 'x' in ff and 0755 or 0644, 'l' in ff, ctx[f].data)

tests/test-archive

@@ -108,6 +108,14 b' if [ -f rev-0.tar ]; then'
     echo 'rev-0.tar created'
 fi
 
+echo '% test .hg_archival.txt'
+hg archive ../test-tags
+cat ../test-tags/.hg_archival.txt
+hg tag -r 2 mytag
+hg tag -r 2 anothertag
+hg archive -r 2 ../test-lasttag
+cat ../test-lasttag/.hg_archival.txt
+
 hg archive -t bogus test.bogus
 
 echo % server errors

tests/test-archive.out

@@ -57,6 +57,17 b' test-TIP/bar'
 test-TIP/baz/bletch
 test-TIP/foo
 rev-0.tar created
+% test .hg_archival.txt
+repo: daa7f7c60e0a224faa4ff77ca41b2760562af264
+node: 2c0277f05ed49d1c8328fb9ba92fba7a5ebcb33e
+branch: default
+latesttag: null
+latesttagdistance: 3
+repo: daa7f7c60e0a224faa4ff77ca41b2760562af264
+node: 2c0277f05ed49d1c8328fb9ba92fba7a5ebcb33e
+branch: default
+tag: anothertag
+tag: mytag
 abort: unknown archive type 'bogus'
 % server errors
 % empty repo