chore: remove once_cell dependency from multiple crates (#4154)

This commit removes the `once_cell` dependency from `Cargo.toml` files
in the `codex-rs` and `apply-patch` directories, replacing its usage
with `std::sync::LazyLock` and `std::sync::OnceLock` where applicable.
This change simplifies the dependency tree and utilizes standard library
features for lazy initialization.

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codex-rs/Cargo.lock

@@ -595,7 +595,6 @@ version = "0.0.0"
 dependencies = [
  "anyhow",
  "assert_cmd",
- "once_cell",
  "pretty_assertions",
  "similar",
  "tempfile",
@@ -956,7 +955,6 @@ dependencies = [
  "lazy_static",
  "libc",
  "mcp-types",
- "once_cell",
  "path-clean",
  "pathdiff",
  "pretty_assertions",

codex-rs/Cargo.toml

@@ -94,7 +94,6 @@ maplit = "1.0.2"
 mime_guess = "2.0.5"
 multimap = "0.10.0"
 nucleo-matcher = "0.3.1"
-once_cell = "1"
 openssl-sys = "*"
 os_info = "3.12.0"
 owo-colors = "4.2.0"

codex-rs/apply-patch/Cargo.toml

@@ -20,7 +20,6 @@ similar = { workspace = true }
 thiserror = { workspace = true }
 tree-sitter = { workspace = true }
 tree-sitter-bash = { workspace = true }
-once_cell = { workspace = true }
 
 [dev-dependencies]
 assert_cmd = { workspace = true }

codex-rs/apply-patch/src/lib.rs

@@ -6,10 +6,10 @@ use std::collections::HashMap;
 use std::path::Path;
 use std::path::PathBuf;
 use std::str::Utf8Error;
+use std::sync::LazyLock;
 
 use anyhow::Context;
 use anyhow::Result;
-use once_cell::sync::Lazy;
 pub use parser::Hunk;
 pub use parser::ParseError;
 use parser::ParseError::*;
@@ -351,7 +351,7 @@ fn extract_apply_patch_from_bash(
     // also run an arbitrary query against the AST. This is useful for understanding
     // how tree-sitter parses the script and whether the query syntax is correct. Be sure
     // to test both positive and negative cases.
-    static APPLY_PATCH_QUERY: Lazy<Query> = Lazy::new(|| {
+    static APPLY_PATCH_QUERY: LazyLock<Query> = LazyLock::new(|| {
         let language = BASH.into();
         #[expect(clippy::expect_used)]
         Query::new(

codex-rs/tui/Cargo.toml

@@ -53,7 +53,6 @@ image = { workspace = true, features = [
 itertools = { workspace = true }
 lazy_static = { workspace = true }
 mcp-types = { workspace = true }
-once_cell = { workspace = true }
 path-clean = { workspace = true }
 rand = { workspace = true }
 ratatui = { workspace = true, features = [

codex-rs/tui/src/session_log.rs

@@ -2,27 +2,27 @@ use std::fs::File;
 use std::fs::OpenOptions;
 use std::io::Write;
 use std::path::PathBuf;
+use std::sync::LazyLock;
 use std::sync::Mutex;
+use std::sync::OnceLock;
 
 use codex_core::config::Config;
 use codex_core::protocol::Op;
-use once_cell::sync::Lazy;
-use once_cell::sync::OnceCell;
 use serde::Serialize;
 use serde_json::json;
 
 use crate::app_event::AppEvent;
 
-static LOGGER: Lazy<SessionLogger> = Lazy::new(SessionLogger::new);
+static LOGGER: LazyLock<SessionLogger> = LazyLock::new(SessionLogger::new);
 
 struct SessionLogger {
-    file: OnceCell<Mutex<File>>,
+    file: OnceLock<Mutex<File>>,
 }
 
 impl SessionLogger {
     fn new() -> Self {
         Self {
-            file: OnceCell::new(),
+            file: OnceLock::new(),
         }
     }
 
@@ -37,11 +37,7 @@ impl SessionLogger {
         }
 
         let file = opts.open(path)?;
-        // If already initialized, ignore and succeed.
-        if self.file.get().is_some() {
-            return Ok(());
-        }
-        let _ = self.file.set(Mutex::new(file));
+        self.file.get_or_init(|| Mutex::new(file));
         Ok(())
     }