annotate: append newline after non newline-terminated file listings

The last line of a non newline-terminated file would mix with the first line of
the next file in multiple-file listings before this patch.

Possible compatibility issue: no longer possible to tell from the annotate
output if the file is terminated by new line or not.

mercurial/commands.py

@@ -299,6 +299,9 b' def annotate(ui, repo, *pats, **opts):'
             for p, l in zip(zip(*pieces), lines):
                 ui.write("%s: %s" % ("".join(p), l[1]))
 
+            if lines and not lines[-1][1].endswith('\n'):
+                ui.write('\n')
+
 @command('archive',
     [('', 'no-decode', None, _('do not pass files through decoders')),
     ('p', 'prefix', '', _('directory prefix for files in archive'),

tests/test-annotate.t

@@ -255,6 +255,18 b' missing file'
   abort: nosuchfile: no such file in rev e9e6b4fa872f
   [255]
 
+annotate file without '\n' on last line
+
+  $ printf "" > c
+  $ hg ci -A -m test -u nobody -d '1 0'
+  adding c
+  $ hg annotate c
+  $ printf "a\nb" > c
+  $ hg ci -m test
+  $ hg annotate c
+  [0-9]+: a (re)
+  [0-9]+: b (re)
+
 Test annotate with whitespace options
 
   $ cd ..