implement reverting block state predictions on ack

2 files changed, 100 insertions, 0 deletions

diff --git a/azalea-client/tests/mine_block_rollback.rs b/azalea-client/tests/mine_block_rollback.rs
new file mode 100644
index 00000000..e9b46d13
--- /dev/null
+++ b/azalea-client/tests/mine_block_rollback.rs
@@ -0,0 +1,49 @@
+use azalea_client::{mining::StartMiningBlockEvent, test_utils::prelude::*};
+use azalea_core::{
+    position::{BlockPos, ChunkPos},
+    resource_location::ResourceLocation,
+};
+use azalea_protocol::packets::{
+    ConnectionProtocol,
+    game::{ClientboundBlockChangedAck, ClientboundBlockUpdate},
+};
+use azalea_registry::{Block, DataRegistry, DimensionType};
+
+#[test]
+fn test_mine_block_rollback() {
+    init_tracing();
+
+    let mut simulation = Simulation::new(ConnectionProtocol::Game);
+    simulation.receive_packet(make_basic_login_packet(
+        DimensionType::new_raw(0),
+        ResourceLocation::new("azalea:overworld"),
+    ));
+
+    simulation.receive_packet(make_basic_empty_chunk(ChunkPos::new(0, 0), (384 + 64) / 16));
+    simulation.tick();
+
+    let pos = BlockPos::new(1, 2, 3);
+    simulation.receive_packet(ClientboundBlockUpdate {
+        pos,
+        // tnt is used for this test because it's insta-mineable so we don't have to waste ticks
+        // waiting
+        block_state: Block::Tnt.into(),
+    });
+    simulation.tick();
+    assert_eq!(simulation.get_block_state(pos), Some(Block::Tnt.into()));
+    println!("set serverside tnt");
+
+    simulation.send_event(StartMiningBlockEvent {
+        entity: simulation.entity,
+        position: pos,
+    });
+    simulation.tick();
+    assert_eq!(simulation.get_block_state(pos), Some(Block::Air.into()));
+    println!("set clientside air");
+
+    // server didn't send the new block, so the change should be rolled back
+    simulation.receive_packet(ClientboundBlockChangedAck { seq: 1 });
+    simulation.tick();
+    assert_eq!(simulation.get_block_state(pos), Some(Block::Tnt.into()));
+    println!("reset serverside tnt");
+}
diff --git a/azalea-client/tests/mine_block_without_rollback.rs b/azalea-client/tests/mine_block_without_rollback.rs
new file mode 100644
index 00000000..02fb1a77
--- /dev/null
+++ b/azalea-client/tests/mine_block_without_rollback.rs
@@ -0,0 +1,51 @@
+use azalea_client::{mining::StartMiningBlockEvent, test_utils::prelude::*};
+use azalea_core::{
+    position::{BlockPos, ChunkPos},
+    resource_location::ResourceLocation,
+};
+use azalea_protocol::packets::{
+    ConnectionProtocol,
+    game::{ClientboundBlockChangedAck, ClientboundBlockUpdate},
+};
+use azalea_registry::{Block, DataRegistry, DimensionType};
+
+#[test]
+fn test_mine_block_without_rollback() {
+    init_tracing();
+
+    let mut simulation = Simulation::new(ConnectionProtocol::Game);
+    simulation.receive_packet(make_basic_login_packet(
+        DimensionType::new_raw(0),
+        ResourceLocation::new("azalea:overworld"),
+    ));
+
+    simulation.receive_packet(make_basic_empty_chunk(ChunkPos::new(0, 0), (384 + 64) / 16));
+    simulation.tick();
+
+    let pos = BlockPos::new(1, 2, 3);
+    simulation.receive_packet(ClientboundBlockUpdate {
+        pos,
+        // tnt is used for this test because it's insta-mineable so we don't have to waste ticks
+        // waiting
+        block_state: Block::Tnt.into(),
+    });
+    simulation.tick();
+    assert_eq!(simulation.get_block_state(pos), Some(Block::Tnt.into()));
+
+    simulation.send_event(StartMiningBlockEvent {
+        entity: simulation.entity,
+        position: pos,
+    });
+    simulation.tick();
+    assert_eq!(simulation.get_block_state(pos), Some(Block::Air.into()));
+
+    // server acknowledged our change by sending a BlockUpdate + BlockChangedAck, so
+    // no rollback
+    simulation.receive_packet(ClientboundBlockUpdate {
+        pos,
+        block_state: Block::Air.into(),
+    });
+    simulation.receive_packet(ClientboundBlockChangedAck { seq: 1 });
+    simulation.tick();
+    assert_eq!(simulation.get_block_state(pos), Some(Block::Air.into()));
+}