refactor(rust): Remove once_cell in favor of std equivalents

Cargo.toml

@@ -55,7 +55,6 @@ ndarray = { version = "0.16", default-features = false }
 num-traits = "0.2"
 numpy = "0.23"
 object_store = { version = "0.11", default-features = false }
-once_cell = "1"
 parking_lot = "0.12"
 percent-encoding = "2.3"
 pin-project-lite = "0.2"

crates/polars-core/Cargo.toml

@@ -29,7 +29,6 @@ indexmap = { workspace = true }
 itoa = { workspace = true }
 ndarray = { workspace = true, optional = true }
 num-traits = { workspace = true }
-once_cell = { workspace = true }
 rand = { workspace = true, optional = true, features = ["small_rng", "std"] }
 rand_distr = { workspace = true, optional = true }
 rayon = { workspace = true }

crates/polars-core/src/chunked_array/logical/categorical/string_cache.rs

@@ -1,10 +1,9 @@
 use std::hash::{Hash, Hasher};
 use std::sync::atomic::{AtomicBool, AtomicU32, Ordering};
-use std::sync::{Mutex, RwLock, RwLockReadGuard, RwLockWriteGuard};
+use std::sync::{LazyLock, Mutex, RwLock, RwLockReadGuard, RwLockWriteGuard};
 
 use hashbrown::hash_table::Entry;
 use hashbrown::HashTable;
-use once_cell::sync::Lazy;
 use polars_utils::aliases::PlRandomState;
 use polars_utils::pl_str::PlSmallStr;
 
@@ -250,4 +249,4 @@ impl StringCache {
     }
 }
 
-pub(crate) static STRING_CACHE: Lazy<StringCache> = Lazy::new(Default::default);
+pub(crate) static STRING_CACHE: LazyLock<StringCache> = LazyLock::new(Default::default);

crates/polars-core/src/chunked_array/object/registry.rs

@@ -5,11 +5,10 @@
 use std::any::Any;
 use std::fmt::{Debug, Formatter};
 use std::ops::Deref;
-use std::sync::{Arc, RwLock};
+use std::sync::{Arc, LazyLock, RwLock};
 
 use arrow::array::ArrayRef;
 use arrow::datatypes::ArrowDataType;
-use once_cell::sync::Lazy;
 use polars_utils::pl_str::PlSmallStr;
 
 use crate::chunked_array::object::builder::ObjectChunkedBuilder;
@@ -36,7 +35,8 @@ impl Debug for ObjectRegistry {
     }
 }
 
-static GLOBAL_OBJECT_REGISTRY: Lazy<RwLock<Option<ObjectRegistry>>> = Lazy::new(Default::default);
+static GLOBAL_OBJECT_REGISTRY: LazyLock<RwLock<Option<ObjectRegistry>>> =
+    LazyLock::new(Default::default);
 
 /// This trait can be registered, after which that global registration
 /// can be used to materialize object types

crates/polars-core/src/chunked_array/temporal/mod.rs

@@ -8,6 +8,9 @@ mod datetime;
 mod duration;
 #[cfg(feature = "dtype-time")]
 mod time;
+#[cfg(feature = "timezones")]
+use std::sync::LazyLock;
+
 #[cfg(feature = "dtype-date")]
 use chrono::NaiveDate;
 use chrono::NaiveDateTime;
@@ -16,8 +19,6 @@ use chrono::NaiveTime;
 #[cfg(feature = "timezones")]
 use chrono_tz::Tz;
 #[cfg(feature = "timezones")]
-use once_cell::sync::Lazy;
-#[cfg(feature = "timezones")]
 use polars_utils::pl_str::PlSmallStr;
 #[cfg(all(feature = "regex", feature = "timezones"))]
 use regex::Regex;
@@ -38,7 +39,8 @@ static FIXED_OFFSET_PATTERN: &str = r#"(?x)
     $
     "#;
 #[cfg(feature = "timezones")]
-static FIXED_OFFSET_RE: Lazy<Regex> = Lazy::new(|| Regex::new(FIXED_OFFSET_PATTERN).unwrap());
+static FIXED_OFFSET_RE: LazyLock<Regex> =
+    LazyLock::new(|| Regex::new(FIXED_OFFSET_PATTERN).unwrap());
 
 #[cfg(feature = "timezones")]
 pub fn validate_time_zone(tz: &str) -> PolarsResult<()> {

crates/polars-core/src/lib.rs

@@ -27,18 +27,17 @@ pub mod testing;
 #[cfg(test)]
 mod tests;
 
-use std::sync::Mutex;
+use std::sync::{LazyLock, Mutex};
 use std::time::{SystemTime, UNIX_EPOCH};
 
 pub use datatypes::SchemaExtPl;
 pub use hashing::IdBuildHasher;
-use once_cell::sync::Lazy;
 use rayon::{ThreadPool, ThreadPoolBuilder};
 
 #[cfg(feature = "dtype-categorical")]
 pub use crate::chunked_array::logical::categorical::string_cache::*;
 
-pub static PROCESS_ID: Lazy<u128> = Lazy::new(|| {
+pub static PROCESS_ID: LazyLock<u128> = LazyLock::new(|| {
     SystemTime::now()
         .duration_since(UNIX_EPOCH)
         .unwrap()
@@ -47,7 +46,7 @@ pub static PROCESS_ID: Lazy<u128> = Lazy::new(|| {
 
 // this is re-exported in utils for polars child crates
 #[cfg(not(target_family = "wasm"))] // only use this on non wasm targets
-pub static POOL: Lazy<ThreadPool> = Lazy::new(|| {
+pub static POOL: LazyLock<ThreadPool> = LazyLock::new(|| {
     let thread_name = std::env::var("POLARS_THREAD_NAME").unwrap_or_else(|_| "polars".to_string());
     ThreadPoolBuilder::new()
         .num_threads(
@@ -65,7 +64,7 @@ pub static POOL: Lazy<ThreadPool> = Lazy::new(|| {
 });
 
 #[cfg(all(target_os = "emscripten", target_family = "wasm"))] // Use 1 rayon thread on emscripten
-pub static POOL: Lazy<ThreadPool> = Lazy::new(|| {
+pub static POOL: LazyLock<ThreadPool> = LazyLock::new(|| {
     ThreadPoolBuilder::new()
         .num_threads(1)
         .use_current_thread()
@@ -74,10 +73,10 @@ pub static POOL: Lazy<ThreadPool> = Lazy::new(|| {
 });
 
 #[cfg(all(not(target_os = "emscripten"), target_family = "wasm"))] // use this on other wasm targets
-pub static POOL: Lazy<polars_utils::wasm::Pool> = Lazy::new(|| polars_utils::wasm::Pool);
+pub static POOL: LazyLock<polars_utils::wasm::Pool> = LazyLock::new(|| polars_utils::wasm::Pool);
 
 // utility for the tests to ensure a single thread can execute
-pub static SINGLE_LOCK: Lazy<Mutex<()>> = Lazy::new(|| Mutex::new(()));
+pub static SINGLE_LOCK: LazyLock<Mutex<()>> = LazyLock::new(|| Mutex::new(()));
 
 /// Default length for a `.head()` call
 pub(crate) const HEAD_DEFAULT_LENGTH: usize = 10;

crates/polars-core/src/random.rs

@@ -1,10 +1,9 @@
-use std::sync::Mutex;
+use std::sync::{LazyLock, Mutex};
 
-use once_cell::sync::Lazy;
 use rand::prelude::*;
 
-static POLARS_GLOBAL_RNG_STATE: Lazy<Mutex<SmallRng>> =
-    Lazy::new(|| Mutex::new(SmallRng::from_entropy()));
+static POLARS_GLOBAL_RNG_STATE: LazyLock<Mutex<SmallRng>> =
+    LazyLock::new(|| Mutex::new(SmallRng::from_entropy()));
 
 pub(crate) fn get_global_random_u64() -> u64 {
     POLARS_GLOBAL_RNG_STATE.lock().unwrap().next_u64()

crates/polars-expr/Cargo.toml

@@ -14,7 +14,6 @@ arrow = { workspace = true }
 bitflags = { workspace = true }
 hashbrown = { workspace = true }
 num-traits = { workspace = true }
-once_cell = { workspace = true }
 polars-compute = { workspace = true }
 polars-core = { workspace = true, features = ["lazy", "zip_with", "random"] }
 polars-io = { workspace = true, features = ["lazy"] }

crates/polars-expr/src/state/execution_state.rs

@@ -1,10 +1,9 @@
 use std::borrow::Cow;
 use std::sync::atomic::{AtomicBool, AtomicI64, AtomicU8, Ordering};
-use std::sync::{Mutex, RwLock};
+use std::sync::{Mutex, OnceLock, RwLock};
 use std::time::Duration;
 
 use bitflags::bitflags;
-use once_cell::sync::OnceCell;
 use polars_core::config::verbose;
 use polars_core::prelude::*;
 use polars_ops::prelude::ChunkJoinOptIds;
@@ -101,7 +100,7 @@ impl From<u8> for StateFlags {
     }
 }
 
-type CachedValue = Arc<(AtomicI64, OnceCell<DataFrame>)>;
+type CachedValue = Arc<(AtomicI64, OnceLock<DataFrame>)>;
 
 /// State/ cache that is maintained during the Execution of the physical plan.
 pub struct ExecutionState {
@@ -229,7 +228,7 @@ impl ExecutionState {
                 guard
                     .entry(key)
                     .or_insert_with(|| {
-                        Arc::new((AtomicI64::new(cache_hits as i64), OnceCell::new()))
+                        Arc::new((AtomicI64::new(cache_hits as i64), OnceLock::new()))
                     })
                     .clone()
             },

crates/polars-io/Cargo.toml

@@ -35,7 +35,6 @@ memchr = { workspace = true }
 memmap = { workspace = true }
 num-traits = { workspace = true }
 object_store = { workspace = true, optional = true }
-once_cell = { workspace = true }
 percent-encoding = { workspace = true }
 pyo3 = { workspace = true, optional = true }
 rayon = { workspace = true }

crates/polars-io/src/cloud/object_store_setup.rs

@@ -1,8 +1,7 @@
-use std::sync::Arc;
+use std::sync::{Arc, LazyLock};
 
 use object_store::local::LocalFileSystem;
 use object_store::ObjectStore;
-use once_cell::sync::Lazy;
 use polars_core::config::{self, verbose_print_sensitive};
 use polars_error::{polars_bail, to_compute_err, PolarsError, PolarsResult};
 use polars_utils::aliases::PlHashMap;
@@ -18,8 +17,8 @@ use crate::cloud::CloudConfig;
 /// get rate limited when querying the DNS (can take up to 5s).
 /// Other reasons are connection pools that must be shared between as much as possible.
 #[allow(clippy::type_complexity)]
-static OBJECT_STORE_CACHE: Lazy<RwLock<PlHashMap<Vec<u8>, PolarsObjectStore>>> =
-    Lazy::new(Default::default);
+static OBJECT_STORE_CACHE: LazyLock<RwLock<PlHashMap<Vec<u8>, PolarsObjectStore>>> =
+    LazyLock::new(Default::default);
 
 #[allow(dead_code)]
 fn err_missing_feature(feature: &str, scheme: &str) -> PolarsResult<Arc<dyn ObjectStore>> {

crates/polars-io/src/cloud/options.rs

@@ -3,6 +3,7 @@ use std::io::Read;
 #[cfg(feature = "aws")]
 use std::path::Path;
 use std::str::FromStr;
+use std::sync::LazyLock;
 
 #[cfg(feature = "aws")]
 use object_store::aws::AmazonS3Builder;
@@ -20,7 +21,6 @@ pub use object_store::gcp::GoogleConfigKey;
 use object_store::ClientOptions;
 #[cfg(any(feature = "aws", feature = "gcp", feature = "azure"))]
 use object_store::{BackoffConfig, RetryConfig};
-use once_cell::sync::Lazy;
 use polars_error::*;
 #[cfg(feature = "aws")]
 use polars_utils::cache::FastFixedCache;
@@ -41,11 +41,11 @@ use crate::file_cache::get_env_file_cache_ttl;
 use crate::pl_async::with_concurrency_budget;
 
 #[cfg(feature = "aws")]
-static BUCKET_REGION: Lazy<
+static BUCKET_REGION: LazyLock<
     std::sync::Mutex<
         FastFixedCache<polars_utils::pl_str::PlSmallStr, polars_utils::pl_str::PlSmallStr>,
     >,
-> = Lazy::new(|| std::sync::Mutex::new(FastFixedCache::new(32)));
+> = LazyLock::new(|| std::sync::Mutex::new(FastFixedCache::new(32)));
 
 /// The type of the config keys must satisfy the following requirements:
 /// 1. must be easily collected into a HashMap, the type required by the object_crate API.
@@ -91,7 +91,7 @@ impl Default for CloudOptions {
 
 impl CloudOptions {
     pub fn default_static_ref() -> &'static Self {
-        static DEFAULT: Lazy<CloudOptions> = Lazy::new(|| CloudOptions {
+        static DEFAULT: LazyLock<CloudOptions> = LazyLock::new(|| CloudOptions {
             max_retries: 2,
             #[cfg(feature = "file_cache")]
             file_cache_ttl: get_env_file_cache_ttl(),

crates/polars-io/src/file_cache/cache.rs

@@ -1,8 +1,7 @@
 use std::path::Path;
 use std::sync::atomic::AtomicU64;
-use std::sync::{Arc, RwLock};
+use std::sync::{Arc, LazyLock, RwLock};
 
-use once_cell::sync::Lazy;
 use polars_core::config;
 use polars_error::PolarsResult;
 use polars_utils::aliases::PlHashMap;
@@ -13,7 +12,7 @@ use super::file_fetcher::FileFetcher;
 use super::utils::FILE_CACHE_PREFIX;
 use crate::path_utils::{ensure_directory_init, is_cloud_url};
 
-pub static FILE_CACHE: Lazy<FileCache> = Lazy::new(|| {
+pub static FILE_CACHE: LazyLock<FileCache> = LazyLock::new(|| {
     let prefix = FILE_CACHE_PREFIX.as_ref();
     let prefix = Arc::<Path>::from(prefix);
 

crates/polars-io/src/file_cache/cache_lock.rs

@@ -1,14 +1,13 @@
 use std::sync::atomic::AtomicBool;
-use std::sync::{Arc, RwLock, RwLockReadGuard, RwLockWriteGuard};
+use std::sync::{Arc, LazyLock, RwLock, RwLockReadGuard, RwLockWriteGuard};
 use std::time::Duration;
 
 use fs4::fs_std::FileExt;
-use once_cell::sync::Lazy;
 
 use super::utils::FILE_CACHE_PREFIX;
 use crate::pl_async;
 
-pub(super) static GLOBAL_FILE_CACHE_LOCK: Lazy<GlobalLock> = Lazy::new(|| {
+pub(super) static GLOBAL_FILE_CACHE_LOCK: LazyLock<GlobalLock> = LazyLock::new(|| {
     let path = FILE_CACHE_PREFIX.join(".process-lock");
 
     let file = std::fs::OpenOptions::new()

crates/polars-io/src/file_cache/entry.rs

@@ -1,10 +1,9 @@
 use std::io::{Seek, SeekFrom};
 use std::path::{Path, PathBuf};
 use std::sync::atomic::AtomicU64;
-use std::sync::{Arc, Mutex};
+use std::sync::{Arc, LazyLock, Mutex};
 
 use fs4::fs_std::FileExt;
-use once_cell::sync::Lazy;
 use polars_core::config;
 use polars_error::{polars_bail, to_compute_err, PolarsError, PolarsResult};
 
@@ -156,7 +155,7 @@ impl Inner {
             // * Some(true)   => always raise
             // * Some(false)  => never raise
             // * None         => do not raise if fallocate() is not permitted, otherwise raise.
-            static RAISE_ALLOC_ERROR: Lazy<Option<bool>> = Lazy::new(|| {
+            static RAISE_ALLOC_ERROR: LazyLock<Option<bool>> = LazyLock::new(|| {
                 let v = match std::env::var("POLARS_IGNORE_FILE_CACHE_ALLOCATE_ERROR").as_deref() {
                     Ok("1") => Some(false),
                     Ok("0") => Some(true),