static-metric/benches: Use label_enum and get (#352)

* static-metric/benches: Use try_get instead of get

> `fn get()` is only available when label is defined by `label_enum`.

Signed-off-by: Max Inden <[email protected]>

* static-metric/benches: Run rust fmt

Signed-off-by: Max Inden <[email protected]>

* static/metric/benches: Use label_enum for the two dimensions

Signed-off-by: Max Inden <[email protected]>

Author: mxinden

static-metric/benches/benches.rs

@@ -1,7 +1,6 @@
 // Copyright 2019 TiKV Project Authors. Licensed under Apache-2.0.
 
 #![feature(test)]
-#![feature(proc_macro)]
 
 extern crate prometheus;
 extern crate prometheus_static_metric;
@@ -52,13 +51,17 @@ fn bench_static_metrics_handwrite_2(b: &mut Bencher) {
 }
 
 make_static_metric! {
+    label_enum D1 {
+        foo,
+    }
+
+    label_enum D2 {
+        bar,
+    }
+
     struct StaticCounter2: IntCounter {
-        "d1" => {
-            foo,
-        },
-        "d2" => {
-            bar,
-        },
+        "d1" => D1,
+        "d2" => D2,
     }
 }
 
@@ -75,7 +78,7 @@ fn bench_static_metrics_macro(b: &mut Bencher) {
 fn bench_static_metrics_macro_with_lookup(b: &mut Bencher) {
     let counter_vec = IntCounterVec::new(Opts::new("foo", "bar"), &["d1", "d2"]).unwrap();
     let static_counter = StaticCounter2::from(&counter_vec);
-    b.iter(|| static_counter.get("foo").get("bar").inc());
+    b.iter(|| static_counter.get(D1::foo).get(D2::bar).inc());
 }
 
 make_static_metric! {