allow underscors in variables

pospell.py

@@ -135,7 +135,7 @@ def clear(po_path, line, drop_capitalized=False):
         r" - ",  # Drop lone dashes (sometimes used in place of -- or ---)
         r"-\\ ",  # Ignore "MINUS BACKSLASH SPACE" typically used in
         # formulas, like '-\ *π*' but *π* gets removed too
-        r"{[a-z]*?}",  # Sphinx variable
+        r"{[a-z_]*?}",  # Sphinx variable
         r"'?-?\b([0-9]+\.)*[0-9]+\.[0-9abcrx]+\b'?",  # Versions
         r"[0-9]+h",  # Hours
         r"%\([a-z_]+?\)s",  # Sphinx variable

tests/test_pospell.py

@@ -45,6 +45,9 @@ def test_clear():
         == "Hier, Marc-André Lemburg a fait"
     )
 
+    # We remove variables
+    assert clear("test", "Starting {days_since} days ago") == "Starting  days ago"
+
     # Drop PEP 440 versions
     assert (
         clear("test", "under python 1.6a1, 1.5.2, and earlier.")