php-ext-source-r3.eclass: Add src_test function

php-ext-source-r3 eclass currently does not provide FEATURES=test support
like php-ext-pecl-r3 eclass does. This commit will add and export the
src_test function from php-ext-pecl-r3 eclass to php-ext-source-r3 eclass
to allow testing of PHP standalone extensions as well.

eclass/php-ext-source-r3.eclass

@@ -12,7 +12,7 @@
 
 inherit autotools
 
-EXPORT_FUNCTIONS src_unpack src_prepare src_configure src_compile src_install
+EXPORT_FUNCTIONS src_unpack src_prepare src_configure src_compile src_install src_test
 
 case ${EAPI} in
 	6) ;;
@@ -230,6 +230,18 @@ php-ext-source-r3_src_install() {
 	php-ext-source-r3_createinifiles
 }
 
+# @FUNCTION: php-ext-source-r3_src_test
+# @DESCRIPTION:
+# Run tests delivered with the standalone PHP extension. Phpize will have generated
+# a run-tests.php file to be executed by `make test`. We only need to
+# force the test suite to run in non-interactive mode.
+php-ext-source-r3_src_test() {
+	for slot in $(php_get_slots); do
+		php_init_slot_env "${slot}"
+		NO_INTERACTION="yes" emake test
+	done
+}
+
 # @FUNCTION: php_get_slots
 # @DESCRIPTION:
 # Get a list of PHP slots contained in both the ebuild's USE_PHP and the