convert/gnuarch: fix cat-log parsing

cat-log parsing was very wrong. It assumed the Summary header
was comming last, which is wrong. Plus the code was buggy because
it was concatenating all headers in the summary.

As parsing GNU Arch isn't trivial, and python email code does it
so well... just use that ;-)

hgext/convert/gnuarch.py

@@ -4,6 +4,7 b' from common import NoRepo, commandline, '
 from mercurial.i18n import _
 from mercurial import util
 import os, shutil, tempfile, stat
+from email.Parser import Parser
 
 class gnuarch_source(converter_source, commandline):
 
@@ -46,6 +47,7 b' class gnuarch_source(converter_source, c'
         self.parents = {}
         self.tags = {}
         self.modecache = {}
+        self.catlogparser = Parser()
 
     def before(self):
         if self.execmd == 'tla':
@@ -70,7 +72,7 b' class gnuarch_source(converter_source, c'
             self.changes[rev] = self.gnuarch_rev(rev)
 
             # Read author, date and summary
-            catlog = self.runlines0('cat-log', '-d', self.path, rev)
+            catlog = self.run0('cat-log', '-d', self.path, rev)
             self._parsecatlog(catlog, rev)
 
             self.parents[rev] = child
@@ -229,20 +231,15 b' class gnuarch_source(converter_source, c'
         return path
 
     def _parsecatlog(self, data, rev):
-        summary = []
-        for l in data:
-            l = l.strip()
-            if summary:
-                summary.append(l)
-            elif l.startswith('Summary:'):
-                summary.append(l[len('Summary: '):])
-            elif l.startswith('Standard-date:'):
-                date = l[len('Standard-date: '):]
-                strdate = util.strdate(date, '%Y-%m-%d %H:%M:%S')
-                self.changes[rev].date = util.datestr(strdate)
-            elif l.startswith('Creator:'):
-                self.changes[rev].author = l[len('Creator: '):]
-        self.changes[rev].summary = '\n'.join(summary)
+        try:
+            catlog = self.catlogparser.parsestr(data)
+            self.changes[rev].date = util.datestr(
+                util.strdate(catlog['Standard-date'],
+                             '%Y-%m-%d %H:%M:%S'))
+            self.changes[rev].author = catlog['Creator']
+            self.changes[rev].summary = catlog['Summary']
+	except Exception, err:
+            raise util.Abort(_('could not parse cat-log of %s') % rev)
 
     def _parsechangeset(self, data, rev):
         for l in data: