Disable benches by default

Cargo.toml

@@ -56,6 +56,7 @@ series = ["vtab"]
 # check for invalid query.
 extra_check = []
 modern_sqlite = ["libsqlite3-sys/bundled_bindings"]
+unstable = []
 
 [dependencies]
 time = "0.1.0"

benches/lib.rs

@@ -1,20 +1,24 @@
-#![feature(test)]
-extern crate test;
+#![cfg_attr(feature = "unstable", feature(test))]
 
-use rusqlite::Connection;
-use test::Bencher;
+#[cfg(feature = "unstable")]
+mod bench {
+    extern crate test;
 
-#[bench]
-fn bench_no_cache(b: &mut Bencher) {
+    use rusqlite::Connection;
+    use test::Bencher;
+
+    #[bench]
+    fn bench_no_cache(b: &mut Bencher) {
         let db = Connection::open_in_memory().unwrap();
         db.set_prepared_statement_cache_capacity(0);
         let sql = "SELECT 1, 'test', 3.14 UNION SELECT 2, 'exp', 2.71";
         b.iter(|| db.prepare(sql).unwrap());
-}
+    }
 
-#[bench]
-fn bench_cache(b: &mut Bencher) {
+    #[bench]
+    fn bench_cache(b: &mut Bencher) {
         let db = Connection::open_in_memory().unwrap();
         let sql = "SELECT 1, 'test', 3.14 UNION SELECT 2, 'exp', 2.71";
         b.iter(|| db.prepare_cached(sql).unwrap());
+    }
 }