Bug#944985: Use of uninitialized value in concatenation or string at…Command/make.pm

[Nicholas D Steeves <nsteeves@gmail.com>]

Package: dh-make-elpa
Version: 0.17
Severity: normal

Hi,

While I initially found this bug using a local bpo of dh-make-elpa,
I've confirmed that 0.17 in sid is affected.

    $ dh-make-elpa
    W: Failed to determine binary packages
    W: Falling back to a single binary package
    Use of uninitialized value in concatenation (.) or string at /usr/share/perl5/DhMakeELPA/Command/make.pm line 144.

Steps to reproduce in a clean sid chroot:

1. apt install git emacs-nox dh-make-elpa
2. git clone -o upstream https://github.com/mhayashi1120/Emacs-wgrep.git
3. mv Emacs-wgrep emacs-wgrep && cd emacs-wgrep
4. git reset --hard 2.3.0
5. git branch --unset-upstream
6. dh-make-elpa --pkg-emacsen
7. Warnings are printed.
8. All els are installed to the main elpa-wgrep package.
9. The value for the "Copyright: " field for "Files: *" is empty.

After consulting make.pm:L144 my guess is that "use of uninitialized
value in concatenation" is caused by empty results when trying to
match patterns such as "Copyright", "(C)", or "©", because none of
these patterns appear anywhere in upstream's tree.

While #8 could be cloned as a wishlist bug (better autodetection of
subpackages), I believe #9 is a normal priority bug where dh-make-elpa
should handle the no-matches-found case, and print something useful
like "no matches found for $list_of_patterns ; manually check all
files, and consider contacting upstream about missing copyright".


Thanks,
Nicholas