Add validate_changes_format utility.

[dak.git] / daklib / formats.py

diff --git a/daklib/formats.py b/daklib/formats.py
index e8ab1d77d205f85db14ee80ea2cd5173e7ce8b3f..aaad2715aac119bd40766d1cef333f9cf2df36df 100644 (file)
--- a/daklib/formats.py
+++ b/daklib/formats.py
@@ -30,3 +30,16 @@ def parse_format(txt):
         format = format[:2]
 
     return format
+
+def validate_changes_format(format, field):
+    """
+    Validate a tuple-representation of a .changes Format: field. Raises
+    UnknownFormatError if the field is invalid, otherwise return type is
+    undefined.
+    """
+
+    if (format < (1, 5) or format > (1, 8)):
+        raise UnknownFormatError, repr(format)
+
+    if field != 'files' and format < (1, 8):
+        raise UnknownFormatError, repr(format)