Add rust and Go benchmarks for encoding json.

src/lib.rs

@@ -0,0 +1,3 @@
+#![feature(test)]
+mod vec3;
+extern crate test;

src/vec3.rs

@@ -0,0 +1,40 @@
+use serde::Serialize;
+
+#[derive(Default, Debug, Serialize, PartialEq, Copy, Clone)]
+pub struct Vec3 {
+    pub x: f32,
+    pub y: f32,
+    pub z: f32,
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use test::Bencher;
+
+    #[test]
+    fn test_vec3_to_json() {
+        let vecs = vec![Vec3 {
+            x: 1.0,
+            y: 2.0,
+            z: 3.0,
+        }];
+        assert_eq!(
+            serde_json::to_string(&vecs).expect("failed to json encode"),
+            r#"[{"x":1.0,"y":2.0,"z":3.0}]"#
+        );
+    }
+
+    #[bench]
+    fn bench_vec3_to_json(b: &mut Bencher) {
+        let vecs: Vec<Vec3> = (0..1000)
+            .map(|i| Vec3 {
+                x: 255. * i as f32 / 1000.,
+                y: 255. * i as f32 / 1000.,
+                z: 255. * i as f32 / 1000.,
+            })
+            .collect();
+
+        b.iter(|| serde_json::to_string(&vecs));
+    }
+}

src/vec3_test.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"encoding/json"
+	"reflect"
+	"testing"
+)
+
+type Vec3 struct {
+	X float32 `json:"x"`
+	Y float32 `json:"y"`
+	Z float32 `json:"z"`
+}
+
+func TestVec3ToJSON(t *testing.T) {
+	vecs := []Vec3{{X: 1.0, Y: 2.0, Z: 3.0}}
+
+	got, err := json.Marshal(vecs)
+	if err != nil {
+		t.Fatalf("Failed to marshal: %v", err)
+	}
+	want := []byte(`[{"x":1,"y":2,"z":3}]`)
+	if !reflect.DeepEqual(want, got) {
+		t.Fatalf("got != want\nGot:  %s\nWant: %s", got, want)
+	}
+}
+
+func BenchmarkVec3ToJSON(b *testing.B) {
+	var vecs []Vec3
+
+	for i := 0; i < 1000; i++ {
+		vecs = append(vecs, Vec3{
+			X: 255. * float32(i) / 1000.,
+			Y: 255. * float32(i) / 1000.,
+			Z: 255. * float32(i) / 1000.,
+		})
+	}
+	for i := 0; i < b.N; i++ {
+		if _, err := json.Marshal(vecs); err != nil {
+			b.Fatalf("Failed to marshal: %v", err)
+		}
+	}
+}