ninja-utils.eclass: Support dev-util/samurai

samurai is a ninja-compatible build tool written in C which
works with cmake, meson and other users of ninja.

It is feature-complete and supports most of the same options
as ninja.

Signed-off-by: orbea <[email protected]>
Signed-off-by: Mike Gilbert <[email protected]>

eclass/ninja-utils.eclass

@@ -26,6 +26,16 @@ esac
 if [[ -z ${_NINJA_UTILS_ECLASS} ]]; then
 _NINJA_UTILS_ECLASS=1
 
+# @ECLASS_VARIABLE: NINJA
+# @PRE_INHERIT
+# @DESCRIPTION:
+# Specify a compatible ninja implementation to be used by eninja().
+# At this point only "ninja" and "samu" are explicitly supported,
+# but other values can be set where NINJA_DEPEND will then be set
+# to a blank variable.
+# The default is set to "ninja".
+: ${NINJA:=ninja}
+
 # @ECLASS_VARIABLE: NINJAOPTS
 # @DEFAULT_UNSET
 # @DESCRIPTION:
@@ -35,6 +45,18 @@ _NINJA_UTILS_ECLASS=1
 
 inherit multiprocessing
 
+case "${NINJA}" in
+	ninja)
+		NINJA_DEPEND=">=dev-util/ninja-1.8.2"
+	;;
+	samu)
+		NINJA_DEPEND="dev-util/samurai"
+	;;
+	*)
+		NINJA_DEPEND=""
+	;;
+esac
+
 # @FUNCTION: eninja
 # @USAGE: [<args>...]
 # @DESCRIPTION:
@@ -48,7 +70,8 @@ eninja() {
 	if [[ -z ${NINJAOPTS+set} ]]; then
 		NINJAOPTS="-j$(makeopts_jobs "${MAKEOPTS}" 999) -l$(makeopts_loadavg "${MAKEOPTS}" 0)"
 	fi
-	set -- ninja -v ${NINJAOPTS} "$@"
+	[[ -n "${NINJA_DEPEND}" ]] || ewarn "Unknown value '${NINJA}' for \${NINJA}"
+	set -- "${NINJA}" -v ${NINJAOPTS} "$@"
 	echo "$@" >&2
 	"$@" || die "${nonfatal_args[@]}" "${*} failed"
 }