tests(app): 🎤 uptime tracker tests for validators missing blocks

crates/core/app/tests/app_tracks_uptime_for_genesis_validator_missing_blocks.rs

@@ -0,0 +1,84 @@
+mod common;
+
+use {
+    self::common::BuilderExt,
+    anyhow::Context,
+    cnidarium::TempStorage,
+    penumbra_app::server::consensus::Consensus,
+    penumbra_genesis::AppState,
+    penumbra_mock_consensus::TestNode,
+    penumbra_stake::{
+        component::validator_handler::validator_store::ValidatorDataRead, validator::Validator,
+    },
+    tap::Tap,
+    tracing::{error_span, info, Instrument},
+};
+
+#[tokio::test]
+async fn app_tracks_uptime_for_genesis_validator_missing_blocks() -> anyhow::Result<()> {
+    // Install a test logger, acquire some temporary storage, and start the test node.
+    let guard = common::set_tracing_subscriber();
+    let storage = TempStorage::new().await?;
+
+    // Start the test node.
+    let mut node = {
+        let app_state = AppState::default();
+        let consensus = Consensus::new(storage.as_ref().clone());
+        TestNode::builder()
+            .single_validator()
+            .with_penumbra_auto_app_state(app_state)?
+            .init_chain(consensus)
+            .await
+    }?;
+
+    // Retrieve the validator definition from the latest snapshot.
+    let Validator { identity_key, .. } = match storage
+        .latest_snapshot()
+        .validator_definitions()
+        .tap(|_| info!("getting validator definitions"))
+        .await?
+        .as_slice()
+    {
+        [v] => v.clone(),
+        unexpected => panic!("there should be one validator, got: {unexpected:?}"),
+    };
+    let get_uptime = || async {
+        storage
+            .latest_snapshot()
+            .get_validator_uptime(&identity_key)
+            .await
+            .expect("should be able to get a validator uptime")
+            .expect("validator uptime should exist")
+    };
+
+    // Show that the uptime starts at with no missed blocks.
+    assert_eq!(
+        get_uptime().await.num_missed_blocks(),
+        0,
+        "no blocks have been missed at genesis"
+    );
+
+    // Jump ahead a few blocks.
+    let height = 4;
+    node.fast_forward(height)
+        .instrument(error_span!("fast forwarding test node {height} blocks"))
+        .await
+        .context("fast forwarding {height} blocks")?;
+
+    // Check the validator's uptime once more. We should have uptime data up to the fourth block,
+    // and the validator should have missed all of the blocks between genesis and now.
+    {
+        let uptime = get_uptime().await;
+        assert_eq!(uptime.as_of_height(), height);
+        assert_eq!(
+            uptime.num_missed_blocks(),
+            /*NB: this is off-by-one */ (height - 1) as usize,
+            "validator should have missed the last {height} blocks"
+        );
+    }
+
+    Ok(())
+        .tap(|_| drop(node))
+        .tap(|_| drop(storage))
+        .tap(|_| drop(guard))
+}