Exit on failure to save COMMIT file

Author: shivammathur

scripts/build.sh

@@ -80,7 +80,9 @@ build_php() {
 save_commit() {
   # Only store commit for unstable versions
   if [ "${stable:?}" = "false" ]; then
-    basename "$(curl -sL https://api.github.com/repos/php/php-src/commits/"${branch:?}" | jq -r .commit.url)" | tee "$INSTALL_ROOT/etc/php/$PHP_VERSION/COMMIT" >/dev/null 2>&1
+    commit="$(basename "$(curl -sL https://api.github.com/repos/php/php-src/commits/"${branch:?}" | jq -r .commit.url)")"
+    [ "$commit" = 'null' ] && exit 1;
+    echo "$commit" | tee "$INSTALL_ROOT/etc/php/$PHP_VERSION/COMMIT" >/dev/null 2>&1
   fi
 }