diff --git a/gulp-sass/gulp-sass-tests.ts b/gulp-sass/gulp-sass-tests.ts
index 429df6572d..b1aeef4b4f 100644
--- a/gulp-sass/gulp-sass-tests.ts
+++ b/gulp-sass/gulp-sass-tests.ts
@@ -12,5 +12,6 @@ gulp.task('sass', function () {
 gulp.task('sass', function () {
     gulp.src('./scss/*.scss')
         .pipe(sass({errLogToConsole: true}))
+        .pipe(sass.sync())
         .pipe(gulp.dest('./css'));
 });
\ No newline at end of file
diff --git a/gulp-sass/gulp-sass.d.ts b/gulp-sass/gulp-sass.d.ts
index 781df0af75..b133461dc7 100644
--- a/gulp-sass/gulp-sass.d.ts
+++ b/gulp-sass/gulp-sass.d.ts
@@ -45,6 +45,8 @@ declare module "gulp-sass" {
 
     interface Sass {
         (opts?: Options): NodeJS.ReadWriteStream;
+        logError(error?: string): void;
+        sync(options?: Options): NodeJS.ReadWriteStream;
     }
 
     var _tmp: Sass;