From 16a2f239379c831ee232b70485058d255adc1074 Mon Sep 17 00:00:00 2001
From: Micah Wylde <micah@arroyo.systems>
Date: Thu, 12 Dec 2024 11:14:23 -0800
Subject: [PATCH] Plan hop(x, x) to tumble(x)

---
 crates/arroyo-planner/src/lib.rs                         | 7 ++++++-
 crates/arroyo-planner/src/test/queries/hop_to_tumble.sql | 7 +++++++
 2 files changed, 13 insertions(+), 1 deletion(-)
 create mode 100644 crates/arroyo-planner/src/test/queries/hop_to_tumble.sql

diff --git a/crates/arroyo-planner/src/lib.rs b/crates/arroyo-planner/src/lib.rs
index 980cd2880..a9972e1af 100644
--- a/crates/arroyo-planner/src/lib.rs
+++ b/crates/arroyo-planner/src/lib.rs
@@ -588,7 +588,12 @@ fn find_window(expression: &Expr) -> Result<Option<WindowType>> {
                         slide
                     );
                 }
-                Ok(Some(WindowType::Sliding { width, slide }))
+                if slide == width {
+                    // a hop window with slide == width is a tumble window
+                    Ok(Some(WindowType::Tumbling { width }))
+                } else {
+                    Ok(Some(WindowType::Sliding { width, slide }))
+                }
             }
             "tumble" => {
                 if args.len() != 1 {
diff --git a/crates/arroyo-planner/src/test/queries/hop_to_tumble.sql b/crates/arroyo-planner/src/test/queries/hop_to_tumble.sql
new file mode 100644
index 000000000..fd94cea58
--- /dev/null
+++ b/crates/arroyo-planner/src/test/queries/hop_to_tumble.sql
@@ -0,0 +1,7 @@
+create table impulse with (
+     connector = 'impulse',
+     event_rate = '10'
+);
+
+select count(*) from impulse
+group by hop(interval '10 seconds', interval '10 seconds');
\ No newline at end of file