Support extracting timestamps from blocks

substrate/client/tests/time.rs

@@ -0,0 +1,31 @@
+use std::time::{Duration, SystemTime};
+
+use tokio::time::sleep;
+
+use serai_client::Serai;
+
+mod common;
+use common::serai;
+
+serai_test!(
+  async fn time() {
+    let serai = serai().await;
+
+    let mut number = serai.get_latest_block().await.unwrap().number();
+    let mut done = 0;
+    while done < 3 {
+      // Wait for the next block
+      let block = serai.get_latest_block().await.unwrap();
+      if block.number() == number {
+        sleep(Duration::from_secs(1)).await;
+        continue;
+      }
+      number = block.number();
+
+      // Make sure the time we extract from the block is within 5 seconds of now
+      let now = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap().as_secs();
+      assert!(now.saturating_sub(block.time().unwrap()) < 5);
+      done += 1;
+    }
+  }
+);