uscan for a single text file

[Ole Streicher <olebole@debian.org>]

Hi,

I want to create a watch file for a package that contains a single text
file (which itself has the version into it):

------------------------------8------------------------------------
version=3
http://www.ngdc.noaa.gov/IAGA/vmod/igrf.html igrf(\d+)coeffs.txt \
 debian debian/repackage.sh
------------------------------8------------------------------------

The "repackage.sh" script would then just create a tarball:

------------------------------8------------------------------------
#!/bin/sh
set -e

VERSION=$2
BASEDIR=$(dirname $3)

cd $BASEDIR
tar cf igrf-coefficients_$VERSION.orig.tar igrf${VERSION}coeffs.txt
rm -f igrf${VERSION}coeffs.txt
xz igrf-coefficients_$VERSION.orig.tar
exec uupdate --no-symlink --upstream-version ${VERSION} igrf_${VERSION}.orig.tar.xz
------------------------------8------------------------------------

However, when I run this, uscan complaints:

------------------------------8------------------------------------
$ uscan 
uscan: Newest version of igrf-coefficients on remote site is 12, local version is 10
uscan:    => Newer package available from
      http://www.ngdc.noaa.gov/IAGA/vmod/igrf12coeffs.txt
Parameter ../igrf12coeffs.txt does not look like a tar archive or a zip file. at /usr/bin/mk-origtargz line 375.
uscan: error: mk-origtargz --package igrf-coefficients --version 12 --compression gzip --directory .. --copyright-file debian/copyright ../igrf12coeffs.txt gave error exit status 255
------------------------------8------------------------------------

--debug does not show more here.
What is wrong here? I thought that mk-orig.tar.gz should be called only
when it is a tar archive?

Best

Ole