--- /usr/portage/sci-mathematics/mathematica/mathematica-13.3.1.ebuild	2023-09-27 11:10:36.000000000 +0200
+++ mathematica-13.3.1.ebuild	2023-10-07 22:39:06.705798132 +0200
@@ -3,12 +3,11 @@
 
 EAPI=8
 
-CHECKREQS_DISK_BUILD=20G
 inherit check-reqs desktop unpacker xdg
 
 DESCRIPTION="Wolfram Mathematica"
 HOMEPAGE="https://www.wolfram.com/mathematica/"
-SRC_URI="Mathematica_${PV}_BNDL_LINUX.sh"
+SRC_URI="doc? ( Mathematica_${PV}_BNDL_LINUX.sh ) !doc? ( Mathematica_${PV}_LINUX.sh )"
 S="${WORKDIR}"
 
 LICENSE="all-rights-reserved"
@@ -58,6 +57,16 @@
 # we might as well list all files in all QA variables...
 QA_PREBUILT="opt/*"
 
+pkg_pretend() {
+	CHECKREQS_DISK_BUILD="$(usex doc 20G 10G)"
+	check-reqs_pkg_pretend
+}
+
+pkg_setup() {
+	CHECKREQS_DISK_BUILD="$(usex doc 20G 10G)"
+	check-reqs_pkg_setup
+}
+
 src_unpack() {
 	/bin/sh "${DISTDIR}/${A}" --nox11 --keep --target "${S}/unpack_app" -- "-help" || die
 }
@@ -79,11 +88,6 @@
 	/bin/sh "Unix/Installer/MathInstaller" -auto "-targetdir=${S}/${M_TARGET}" "-execdir=${S}/opt/bin" || die
 	popd > /dev/null || die
 
-	if ! use doc; then
-		einfo "Removing documentation"
-		rm -r "${S}/${M_TARGET}/Documentation" || die
-	fi
-
 	# fix world writable file QA problem for files
 	while IFS= read -r -d '' i; do
 		chmod o-w "${i}" || die