gnulib-tool --update fails w/ conditional-dependencies

[Nick Bowler]

Hi folks,

Commit b283b5d518e1 ("gnulib-tool: Refactor inctests variable.")
broke gnulib-tool's update mode for me.  I am using the
conditional-dependencies feature.  Attempting to run
gnulib-tool --update on one of my projects prints the following
message:

  gnulib-tool: option --conditional-dependencies is not supported with 
--with-tests

which is surprising as I am not using --with-tests.  The behaviour is
identical even if I explicitly pass --without-tests.

Closer inspection reveals that on line 4448 of gnulib-tool we have the
following shell condition:

  if test "$cond_dependencies" = true && $inctests; then
    [ ... prints the error message and bails ...]
  fi

and when my shell executes this condition, inctests is set to the empty
string and the condition passes.

I can reproduce easily as follows:

  $GNULIB/gnulib-tool --import --conditional-dependencies
  $GNULIB/gnulib-tool --update

Reverting the aforementioned commit resolves the issue.

Thanks,
-- 
Nick Bowler, Elliptic Technologies (http://www.elliptictech.com/)