please.sh upgrade: make sure not to decrement pkgrel

It is possible that there were no changes since the latest release, and
that the pkgrel was not forced to a higher number manually. In this
case, we might set it to 1 by mistake (instead of erroring out because
nothing needs to be built).

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

please.sh

@@ -2276,6 +2276,14 @@ maybe_force_pkgrel () {
 			sed -i "s/^\\(pkgrel=\\).*/\\1"$((1+${blame##*=}))/ PKGBUILD
 		fi
 	fi
+
+	# make sure that we did not downgrade
+	if test 0 -ge $(($(git diff HEAD -- PKGBUILD |
+		sed -n 's/^\([-+]\)pkgrel=\([0-9]*\)$/\1\2/p' | tr -d '\n')))
+	then
+		die 'pkgrel must not be downgraded:\n\n%s\n' \
+			"$(git diff HEAD -- PKGBUILD)"
+	fi
 }
 
 # --force overwrites existing an Git tag, or existing package files