From 48d04dc7d0acb5581afba8b8ab68699de7210111 Mon Sep 17 00:00:00 2001
From: Ethan Donowitz <ethan@readyset.io>
Date: Tue, 23 Apr 2024 17:38:14 -0400
Subject: [PATCH] treewide: Remove once_cell crate

`OnceCell` was added to the Rust standard library a while back, so it is
no longer necessary to use the 3rd party crate. This commit removes the
crate, replacing our only usage of `OnceCell` with `OnceLock`, which is
a thread-safe alternative.

Change-Id: Ifdb622c34c24ff40836276e25d2db8c33a2694df
---
 Cargo.lock                         | 2 --
 Cargo.toml                         | 1 -
 readyset-server/Cargo.toml         | 1 -
 readyset-server/src/metrics/mod.rs | 5 +++--
 readyset-tracing/Cargo.toml        | 1 -
 5 files changed, 3 insertions(+), 7 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 07a8dbd526..55a50240b2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4959,7 +4959,6 @@ dependencies = [
  "nom",
  "nom-sql",
  "num_cpus",
- "once_cell",
  "parking_lot 0.12.1",
  "petgraph",
  "pin-project",
@@ -5075,7 +5074,6 @@ version = "0.1.0"
 dependencies = [
  "clap 4.3.2",
  "lazy_static",
- "once_cell",
  "opentelemetry",
  "opentelemetry-otlp",
  "opentelemetry-semantic-conventions",
diff --git a/Cargo.toml b/Cargo.toml
index 4e98e58331..5fd0807a78 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -153,7 +153,6 @@ nom_locate = "4.0.0"
 notify = "6.1.1"
 num-integer = "0.1.44"
 num_cpus = "1.16.0"
-once_cell = "1.14"
 opentelemetry = "0.21.0"
 opentelemetry-otlp = "0.14.0"
 opentelemetry-semantic-conventions = "0.13"
diff --git a/readyset-server/Cargo.toml b/readyset-server/Cargo.toml
index 32670f4f01..49f1387196 100644
--- a/readyset-server/Cargo.toml
+++ b/readyset-server/Cargo.toml
@@ -64,7 +64,6 @@ sha1 = { workspace = true }
 derive_more = { workspace = true }
 streaming-iterator = { workspace = true }
 proptest = { workspace = true }
-once_cell = { workspace = true }
 enum-kinds = { workspace = true }
 slotmap = { workspace = true }
 tikv-jemalloc-ctl = { workspace = true }
diff --git a/readyset-server/src/metrics/mod.rs b/readyset-server/src/metrics/mod.rs
index 36e1f6211f..8c1ad80dc5 100644
--- a/readyset-server/src/metrics/mod.rs
+++ b/readyset-server/src/metrics/mod.rs
@@ -1,6 +1,7 @@
 //! Support for recording and exporting in-memory metrics using the [`metrics`] crate
 
-use once_cell::sync::OnceCell;
+use std::sync::OnceLock;
+
 use thiserror::Error;
 
 pub use crate::metrics::composite_recorder::{CompositeMetricsRecorder, RecorderType};
@@ -14,7 +15,7 @@ mod recorders;
 
 /// The type of the static, globally accessible metrics recorder.
 type GlobalRecorder = CompositeMetricsRecorder;
-static METRICS_RECORDER: OnceCell<&'static GlobalRecorder> = OnceCell::new();
+static METRICS_RECORDER: OnceLock<&'static GlobalRecorder> = OnceLock::new();
 
 /// Error value returned from [`install_global_recorder`] if a metrics recorder is already set.
 ///
diff --git a/readyset-tracing/Cargo.toml b/readyset-tracing/Cargo.toml
index 9f588d069d..d108eeeaf4 100644
--- a/readyset-tracing/Cargo.toml
+++ b/readyset-tracing/Cargo.toml
@@ -7,7 +7,6 @@ edition = "2021"
 
 [dependencies]
 clap = { workspace = true, features = ["derive","env"] }
-once_cell = { workspace = true }
 parking_lot = { workspace = true }
 rand = { workspace = true }
 serde = { workspace = true, features = ["derive"] }