diffutils-2.7.4: diff --exclude doesn't work

[Bruno Haible]

The --exclude option with wildcards doesn't work in diff-2.7.4 any more.

Example:

$ LANG=C diff-2.7.4 -r -c3 --exclude='*.po*' --exclude='*.info*' 
--exclude='*.html' --exclude=Makefile.in --exclude=configure gettext-6 
gettext-7 | grep '^diff' | sed -e 's/^.* //'
gettext-7/Admin/plans
gettext-7/aclocal.m4
gettext-7/doc/Makefile.am
gettext-7/doc/gettext.info
gettext-7/doc/gettext.info-1
gettext-7/doc/gettext.info-4
gettext-7/doc/gettext.info-5
gettext-7/doc/gettext.info-6
gettext-7/doc/gettext.info-7
gettext-7/doc/gettext.texi
gettext-7/doc/gettext_1.html
gettext-7/doc/gettext_10.html
gettext-7/doc/gettext_11.html
gettext-7/doc/gettext_12.html
gettext-7/doc/gettext_13.html
gettext-7/doc/gettext_14.html
gettext-7/doc/gettext_15.html
gettext-7/doc/gettext_16.html
gettext-7/doc/gettext_2.html
gettext-7/doc/gettext_3.html
gettext-7/doc/gettext_4.html
gettext-7/doc/gettext_5.html
gettext-7/doc/gettext_6.html
gettext-7/doc/gettext_7.html
gettext-7/doc/gettext_8.html
gettext-7/doc/gettext_9.html
gettext-7/doc/gettext_foot.html
gettext-7/doc/gettext_toc.html
gettext-7/doc/stamp-vti
gettext-7/doc/version.texi
gettext-7/intl-java/javadoc1/AllNames.html
gettext-7/intl-java/javadoc1/gnu.gettext.GettextResource.html
gettext-7/intl-java/javadoc1/packages.html
gettext-7/intl-java/javadoc1/tree.html
gettext-7/intl-java/javadoc2/allclasses-frame.html
gettext-7/intl-java/javadoc2/deprecated-list.html
gettext-7/intl-java/javadoc2/gnu/gettext/GettextResource.html
gettext-7/intl-java/javadoc2/help-doc.html
gettext-7/intl-java/javadoc2/index-all.html
gettext-7/intl-java/javadoc2/index.html
gettext-7/intl-java/javadoc2/overview-tree.html
gettext-7/intl-java/javadoc2/packages.html
gettext-7/intl-java/javadoc2/serialized-form.html
gettext-7/man/msgexec.1
gettext-7/man/msgexec.1.html
gettext-7/po/cs.po
gettext-7/po/da.po
gettext-7/po/de.po
gettext-7/po/el.po
gettext-7/po/address@hidden
gettext-7/po/address@hidden
gettext-7/po/es.po
gettext-7/po/et.po
gettext-7/po/fr.po
gettext-7/po/gettext.pot
gettext-7/po/gl.po
gettext-7/po/id.po
gettext-7/po/it.po
gettext-7/po/ja.po
gettext-7/po/ko.po
gettext-7/po/nl.po
gettext-7/po/nn.po
gettext-7/po/no.po
gettext-7/po/pl.po
gettext-7/po/pt.po
gettext-7/po/pt_BR.po
gettext-7/po/ru.po
gettext-7/po/sk.po
gettext-7/po/sl.po
gettext-7/po/sv.po
gettext-7/po/tr.po
gettext-7/po/zh.po
gettext-7/src/msgfilter.c
gettext-7/src/xgettext.c
gettext-7/tests/Makefile.am

whereas

$ LANG=C diff-2.7 -r -c3 --exclude='*.po*' --exclude='*.info*' 
--exclude='*.html' --exclude=Makefile.in --exclude=configure gettext-6 
gettext-7 | grep '^diff' | sed -e 's/^.* //'
gettext-7/Admin/plans
gettext-7/aclocal.m4
gettext-7/doc/Makefile.am
gettext-7/doc/gettext.texi
gettext-7/doc/stamp-vti
gettext-7/doc/version.texi
gettext-7/man/msgexec.1
gettext-7/src/msgfilter.c
gettext-7/src/xgettext.c
gettext-7/tests/Makefile.am

In fact, diff-2.7.4 doesn't even call the fnmatch() function at all. The
reason being that in exclude.c:172 the variable 'matcher' always points
to fnmatch_no_wildcards (all options values being 0 - there is nowhere code
to add EXCLUDE_WILDCARDS to options).

I don't understand how you can make such profound modifications to "diff"
without any testsuite.

Bruno