record: add an option to backup all wc modifications

Also, don't create a backup dir if we have no files to backup.

This is essential for qrefresh --interactive. Since we can't
select individual files to qrefresh without eliminating already
present changes, we have to backup all changes in the working
copy to avoid refreshing unaccepted hunks.

(thanks to Patrick for the idea)

hgext/record.py

@@ -374,7 +374,7 b' def record(ui, repo, *pats, **opts):'
 
     This command is not available when committing a merge.'''
 
-    dorecord(ui, repo, commands.commit, 'commit', *pats, **opts)
+    dorecord(ui, repo, commands.commit, 'commit', False, *pats, **opts)
 
 
 def qrecord(ui, repo, patch, *pats, **opts):
@@ -395,10 +395,9 b' def qrecord(ui, repo, patch, *pats, **op'
         opts['checkname'] = False
         mq.new(ui, repo, patch, *pats, **opts)
 
-    dorecord(ui, repo, committomq, 'qnew', *pats, **opts)
+    dorecord(ui, repo, committomq, 'qnew', False, *pats, **opts)
 
-
-def dorecord(ui, repo, commitfunc, cmdsuggest, *pats, **opts):
+def dorecord(ui, repo, commitfunc, cmdsuggest, backupall, *pats, **opts):
     if not ui.interactive():
         raise util.Abort(_('running non-interactively, use %s instead') %
                          cmdsuggest)
@@ -450,18 +449,22 b' def dorecord(ui, repo, commitfunc, cmdsu'
         modified = set(changes[0])
 
         # 2. backup changed files, so we can restore them in the end
+        if backupall:
+            tobackup = changed
+        else:
+            tobackup = [f for f in newfiles if f in modified]
+
         backups = {}
-        backupdir = repo.join('record-backups')
-        try:
-            os.mkdir(backupdir)
-        except OSError, err:
-            if err.errno != errno.EEXIST:
-                raise
+        if tobackup:
+            backupdir = repo.join('record-backups')
+            try:
+                os.mkdir(backupdir)
+            except OSError, err:
+                if err.errno != errno.EEXIST:
+                    raise
         try:
             # backup continues
-            for f in newfiles:
-                if f not in modified:
-                    continue
+            for f in tobackup:
                 fd, tmpname = tempfile.mkstemp(prefix=f.replace('/', '_')+'.',
                                                dir=backupdir)
                 os.close(fd)
@@ -522,7 +525,8 b' def dorecord(ui, repo, commitfunc, cmdsu'
                     # writing it.
                     shutil.copystat(tmpname, repo.wjoin(realname))
                     os.unlink(tmpname)
-                os.rmdir(backupdir)
+                if tobackup:
+                    os.rmdir(backupdir)
             except OSError:
                 pass