announce-gen usage feedback

[Bruno Haible]

Hi Simon,

Two remarks regarding 'announce-gen':

1) I used the command
   $ $GNULIB_SRCDIR/build-aux/announce-gen --release-type stable \
       --package-name libunistring --previous-version 0.9.10 \
       --current-version 1.0 --gpg-key-id F5BE8B267C6A406D \
       --url-directory https://ftp.gnu.org/gnu/libunistring \
       --gnulib-version=v0.1-5095-gb79766eae

and got the error message:

   announce-gen: when specifying gnulib as a tool, you must also specify
   --gnulib-version=V, where V is the result of running git describe
   in the gnulib source directory.
   Try 'announce-gen --help' for more information.

This was confusing, as I did gave --gnulib-version but no --bootstrap-tools
option. To fix this error, I had to add a --bootstrap-tools=... option.
The error message should better have been

   announce-gen: when specifying --gnulib-version, you must also include
   gnulib in the --bootstrap-tools option.
   Try 'announce-gen --help' for more information.

2) The proposed text contained these paragraphs:

   ----------------------------------------------------------------------------
   Here are the SHA1 and SHA256 checksums:

   cd38e3850b2d08a55cce0380d3510e7df83c6306  libunistring-1.0.tar.gz
   PAGEwOSS18IIzjHSXdHSxY8MPtbLvgMsWySM3a0xhUQ  libunistring-1.0.tar.gz
   ebae3103346745bef3534910a5c5afbf72099b2a  libunistring-1.0.tar.xz
   W6tVtJ91137SayV5l+kZtpPyn9ShvCLg5uAkwkbHJ0E  libunistring-1.0.tar.xz

   The SHA256 checksum is base64 encoded, instead of the
   hexadecimal encoding that most checksum tools default to.
   ----------------------------------------------------------------------------

   But since the 'sha256sum' command from coreutils does not have an option
   to display the base64 encoded SHA256 sum, and no tool I know of provides
   a way to convert between hexadecimal and base64 checksums, displaying
   a base64 encoded SHA256 sum is next to useless.

   I ended up rewriting these paragraphs as follows:

   ----------------------------------------------------------------------------
   Here are the SHA1 and SHA256 checksums:

   File: libunistring-1.0.tar.gz
   SHA1 sum:   cd38e3850b2d08a55cce0380d3510e7df83c6306
   SHA256 sum: 3c0184c0e492d7c208ce31d25dd1d2c58f0c3ed6cbbe032c5b248cddad318544

   File: libunistring-1.0.tar.xz
   SHA1 sum:   ebae3103346745bef3534910a5c5afbf72099b2a
   SHA256 sum: 5bab55b49f75d77ed26b257997e919b693f29fd4a1bc22e0e6e024c246c72741
   ----------------------------------------------------------------------------

   How about doing the same in the 'announce-gen' script?

Bruno