Verify PO file format with msginit.

tests/test_build_gettext.py

@@ -9,6 +9,9 @@
     :license: BSD, see LICENSE for details.
 """
 
+import os
+from subprocess import Popen, PIPE
+
 from util import *
 
 
@@ -22,3 +25,22 @@ def test_gettext(app):
     assert (app.outdir / 'contents.pot').isfile()
     # group into sections
     assert (app.outdir / 'subdir.pot').isfile()
+
+    cwd = os.getcwd()
+    os.chdir(app.outdir)
+    try:
+        try:
+            p = Popen(['msginit', '--no-translator', '-i', 'contents.pot'],
+                        stdout=PIPE, stderr=PIPE)
+        except OSError:
+            return  # most likely msginit was not found
+        else:
+            stdout, stderr = p.communicate()
+            if p.returncode != 0:
+                print stdout
+                print stderr
+                del app.cleanup_trees[:]
+                assert False, 'msginit exited with return code %s' % p.returncode
+        assert (app.outdir / 'en_US.po').isfile(), 'msginit failed'
+    finally:
+        os.chdir(cwd)