libmakepkg/lint_pkgbuild: permit versioned optdepends

pacman accepts these, and there is no good reason to be more restrictive
ourselves; we should follow the example of "depends" here.

Update the documentation to actually state that this is supported.
Signed-off-by: Eli Schwartz <eschwartz@archlinux.org>
Signed-off-by: Allan McRae <allan@archlinux.org>

doc/PKGBUILD.5.asciidoc

@@ -212,8 +212,9 @@ underscore and the architecture name e.g., 'checkdepends_x86_64=()'.
 	An array of packages (and accompanying reasons) that are not essential for
 	base functionality, but may be necessary to make full use of the contents
 	of this package. optdepends are currently for informational purposes only
-	and are not utilized by pacman during dependency resolution. The format
-	for specifying optdepends is:
+	and are not utilized by pacman during dependency resolution. Packages in
+	this list follow the same format as depends, with an optional description
+	appended. The format for specifying optdepends descriptions is:
 
 	optdepends=('python: for library bindings')
 +

scripts/libmakepkg/lint_pkgbuild/optdepends.sh.in

@@ -31,15 +31,23 @@ lint_pkgbuild_functions+=('lint_optdepends')
 
 
 lint_optdepends() {
-	local a list name optdepends_list ret=0
-
-	local optdepends_list optdepend name ret=0
+	local optdepends_list optdepend name ver ret=0
 
 	get_pkgbuild_all_split_attributes optdepends optdepends_list
 
-	for optdepend in "${optdepends_list[@]}"; do
-		name=${optdepend%%:[[:space:]]*}
+	# this function requires extglob - save current status to restore later
+	local shellopts=$(shopt -p extglob)
+	shopt -s extglob
+
+	for optdepend in "${optdepends_list[@]%%:[[:space:]]*}"; do
+		name=${optdepend%%@(<|>|=|>=|<=)*}
+		# remove optional epoch in version specifier
+		ver=${optdepend##$name@(<|>|=|>=|<=)?(+([0-9]):)}
 		lint_one_pkgname optdepends "$name" || ret=1
+		if [[ $ver != $optdepend ]]; then
+			# remove optional pkgrel in version specifier
+			check_pkgver "${ver%-+([0-9])?(.+([0-9]))}" optdepends || ret=1
+		fi
 	done
 
 	return $ret