From 64e01c5b87817b46083c3f0a059bca8cb05c016d Mon Sep 17 00:00:00 2001
From: Konstantin Knizhnik <knizhnik@garret.ru>
Date: Mon, 15 May 2023 18:24:35 +0300
Subject: [PATCH] Add removed BufferedHistoricLayerCoverage.contains method

---
 .../src/tenant/layer_map/historic_layer_coverage.rs       | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/pageserver/src/tenant/layer_map/historic_layer_coverage.rs b/pageserver/src/tenant/layer_map/historic_layer_coverage.rs
index a834253cca..d4fdec52a2 100644
--- a/pageserver/src/tenant/layer_map/historic_layer_coverage.rs
+++ b/pageserver/src/tenant/layer_map/historic_layer_coverage.rs
@@ -431,6 +431,14 @@ impl<Value: Clone> BufferedHistoricLayerCoverage<Value> {
         }
     }
 
+    pub fn contains(&self, layer_key: &LayerKey) -> bool {
+        match self.buffer.get(layer_key) {
+            Some(None) => false,                         // layer remove was buffered
+            Some(_) => true,                             // layer insert was buffered
+            None => self.layers.contains_key(layer_key), // no buffered ops for this layer
+        }
+    }
+
     pub fn insert(&mut self, layer_key: LayerKey, value: Value) {
         self.buffer.insert(layer_key, Some(value));
     }