build: when po-check fails, say why and suggest a fix

* Makefile.maint (po-check): Before, when this check failed, it just
spat out a diff mentioning two temporary files.  Now, it tells you
what's wrong and suggests a fix with a patch using the name of the
affected file (rather than temporary file names) in the diff output.

diff --git a/ChangeLog b/ChangeLog
index e7a4f2b3f57df1e4b2451c01f3f69ba0f85faf94..f65fc678071046feef55fbcc8e0d1612192cd2b0 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+Thu Oct 16 19:17:25 +0200 Jim Meyering <meyering@redhat.com>
+
+       build: when po-check fails, say why and suggest a fix
+       * Makefile.maint (po-check): Before, when this check failed, it just
+       spat out a diff mentioning two temporary files.  Now, it tells you
+       what's wrong and suggests a fix with a patch using the name of the
+       affected file (rather than temporary file names) in the diff output.
+
 Thu Oct 16 17:02:00 CEST 2008 Chris Lalancette <clalance@redhat.com>
        * Add support for detecting the partition table type when scanning
        iSCSI volumes.  This is implemented in the

diff --git a/Makefile.maint b/Makefile.maint
index 03800f8905e199eea6a3fa76405f85d1d81f8f9c..49201123f721bf98900627e76c46d356a436d7d3 100644 (file)
--- a/Makefile.maint
+++ b/Makefile.maint
@@ -466,8 +466,12 @@ m4-check:
          && { echo 'Makefile.maint: quote the first arg to AC_DEFUN' 1>&2; \
               exit 1; } || :
 
+fix_po_file_diag = \
+'you have changed the set of files with translatable diagnostics;\n\
+apply the above patch\n'
+
 # Verify that all source files using _() are listed in po/POTFILES.in.
-# FIXME: don't hard-code file names below; use a more general mechanism.
+po_file = po/POTFILES.in
 po-check:
        @if test -f po/POTFILES.in; then                                        \
          grep -E -v '^(#|$$)' po/POTFILES.in                           \
@@ -482,13 +486,14 @@ po-check:
            *.[ch])                                                     \
              base=`expr " $$file" : ' \(.*\)\..'`;                     \
              { test -f $$base.l || test -f $$base.y; } && continue;;   \
-           *) continue;;                               \
+           *) continue;;                                               \
            esac;                                                       \
            files="$$files $$file";                                     \
          done;                                                         \
          grep -E -l '\b(N?_|gettext *)\([^)"]*("|$$)' $$files          \
            | sort -u > $@-2;                                           \
-         diff -u $@-1 $@-2 || exit 1;                                  \
+         diff -u -L $(po_file) -L $(po_file) $@-1 $@-2                 \
+           || { printf '$(ME): '$(fix_po_file_diag) 1>&2; exit 1; };   \
          rm -f $@-1 $@-2;                                              \
        fi