Remove dependency on once_cell

CHANGELOG.md

@@ -122,6 +122,7 @@
 - Update onig_sys dependency to 69.9.1 to fix a gcc build failure #3400 (@CosmicHorrorDev)
 - Add a cargo feature (`vendored-libgit2`) to build with vendored libgit2 version without depending on the system's one #3426 (@0x61nas)
 - Update syntect dependency to v5.3.0 to fix a few minor bugs, see #3410 (@keith-hall)
+- Remove dependency on once_cell #3653 (@cyqsimon)
 
 ## Syntaxes
 

Cargo.toml

@@ -47,7 +47,6 @@ ansi_colours = "^1.2"
 bincode = "1.0"
 console = "0.16.2"
 flate2 = "1.1"
-once_cell = "1.20"
 thiserror = "2.0"
 wild = { version = "2.2", optional = true }
 content_inspector = "0.2.4"
@@ -110,7 +109,6 @@ nix = { version = "0.31", default-features = false, features = ["term"] }
 anyhow = "1.0.97"
 indexmap = { version = "2.13.0", features = ["serde"] }
 itertools = "0.14.0"
-once_cell = "1.20"
 prettyplease = "0.2.37"
 proc-macro2 = "1.0.106"
 quote = "1.0.40"

build/syntax_mapping.rs

@@ -3,12 +3,12 @@ use std::{
     env, fs,
     path::{Path, PathBuf},
     str::FromStr,
+    sync::LazyLock,
 };
 
 use anyhow::{anyhow, bail};
 use indexmap::IndexMap;
 use itertools::Itertools;
-use once_cell::sync::Lazy;
 use proc_macro2::TokenStream;
 use quote::{quote, ToTokens, TokenStreamExt};
 use regex::Regex;
@@ -79,7 +79,7 @@ impl ToTokens for Case {
 
 /// A single matcher.
 ///
-/// Codegen converts this into a `Lazy<Option<GlobMatcher>>`.
+/// Codegen converts this into a `LazyLock<Option<GlobMatcher>>`.
 #[derive(Clone, Debug, PartialEq, Eq, Hash, Deserialize)]
 #[serde(try_from = "RawMatcher")]
 struct Matcher {
@@ -105,7 +105,7 @@ struct Matcher {
 /// - 2024-02-20: allow `{` and `}` (glob brace expansion)
 fn parse_glob(s: &str) -> Result<Vec<MatcherSegment>, anyhow::Error> {
     use MatcherSegment as Seg;
-    static VAR_REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"\$\{([\w\d_]+)\}").unwrap());
+    static VAR_REGEX: LazyLock<Regex> = LazyLock::new(|| Regex::new(r"\$\{([\w\d_]+)\}").unwrap());
 
     let mut segments = vec![];
     let mut text_start = 0;
@@ -186,11 +186,11 @@ impl ToTokens for Matcher {
         let t = match self.segments.as_slice() {
             [] => unreachable!("0-length matcher should never be created"),
             [MatcherSegment::Text(text)] => {
-                quote! { Lazy::new(|| Some(build_matcher_fixed(#text, #case))) }
+                quote! { LazyLock::new(|| Some(build_matcher_fixed(#text, #case))) }
             }
             // parser logic ensures that this case can only happen when there are dynamic segments
             segs @ [_, ..] => {
-                quote! { Lazy::new(|| build_matcher_dynamic(&[ #(#segs),* ], #case)) }
+                quote! { LazyLock::new(|| build_matcher_dynamic(&[ #(#segs),* ], #case)) }
             }
         };
         tokens.append_all(t);
@@ -270,7 +270,7 @@ impl ToTokens for MappingList {
 
         let t = quote! {
             /// Generated by build script from /src/syntax_mapping/builtins/.
-            pub(crate) static BUILTIN_MAPPINGS: [(Lazy<Option<GlobMatcher>>, MappingTarget); #len] = [#(#array_items),*];
+            pub(crate) static BUILTIN_MAPPINGS: [(LazyLock<Option<GlobMatcher>>, MappingTarget); #len] = [#(#array_items),*];
         };
         tokens.append_all(t);
     }

src/assets.rs

@@ -1,9 +1,8 @@
+use std::cell::OnceCell;
 use std::ffi::OsStr;
 use std::fs;
 use std::path::Path;
 
-use once_cell::unsync::OnceCell;
-
 use syntect::highlighting::Theme;
 use syntect::parsing::{SyntaxReference, SyntaxSet};
 
@@ -90,8 +89,14 @@ impl HighlightingAssets {
 
     /// Return the collection of syntect syntax definitions.
     pub fn get_syntax_set(&self) -> Result<&SyntaxSet> {
-        self.syntax_set_cell
-            .get_or_try_init(|| self.serialized_syntax_set.deserialize())
+        // IMPRV: OnceCell::get_mut_or_init is preferable once stabalized
+        match self.syntax_set_cell.get() {
+            Some(set) => Ok(set),
+            None => {
+                let syntax_set = self.serialized_syntax_set.deserialize()?;
+                Ok(self.syntax_set_cell.get_or_init(|| syntax_set))
+            }
+        }
     }
 
     /// Use [Self::get_syntaxes] instead

src/assets/lazy_theme_set.rs

@@ -5,8 +5,6 @@ use std::convert::TryFrom;
 
 use serde_derive::{Deserialize, Serialize};
 
-use once_cell::unsync::OnceCell;
-
 use syntect::highlighting::{Theme, ThemeSet};
 
 /// Same structure as a [`syntect::highlighting::ThemeSet`] but with themes
@@ -31,10 +29,11 @@ impl LazyThemeSet {
     /// Lazily load the given theme
     pub fn get(&self, name: &str) -> Option<&Theme> {
         self.themes.get(name).and_then(|lazy_theme| {
-            lazy_theme
-                .deserialized
-                .get_or_try_init(|| lazy_theme.deserialize())
-                .ok()
+            // IMPRV: OnceCell::get_mut_or_init is preferable once stabalized
+            lazy_theme.deserialized.get().or_else(|| {
+                let deserialized = lazy_theme.deserialize().ok()?;
+                Some(lazy_theme.deserialized.get_or_init(|| deserialized))
+            })
         })
     }
 

src/bin/bat/clap_app.rs

@@ -1,11 +1,11 @@
 use bat::style::StyleComponentList;
 use clap::{crate_name, crate_version, value_parser, Arg, ArgAction, ColorChoice, Command};
-use once_cell::sync::Lazy;
 use std::env;
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
+use std::sync::LazyLock;
 
-static VERSION: Lazy<String> = Lazy::new(|| {
+static VERSION: LazyLock<String> = LazyLock::new(|| {
     #[cfg(feature = "bugreport")]
     let git_version = bugreport::git_version!(fallback = "");
     #[cfg(not(feature = "bugreport"))]

src/bin/bat/directories.rs

@@ -1,8 +1,8 @@
 use std::env;
 use std::path::{Path, PathBuf};
+use std::sync::LazyLock;
 
 use etcetera::BaseStrategy;
-use once_cell::sync::Lazy;
 
 /// Wrapper for 'etcetera' that checks BAT_CACHE_PATH and BAT_CONFIG_DIR and falls back to the
 /// Windows known folder locations on Windows & the XDG Base Directory Specification everywhere else.
@@ -47,5 +47,5 @@ impl BatProjectDirs {
     }
 }
 
-pub static PROJECT_DIRS: Lazy<BatProjectDirs> =
-    Lazy::new(|| BatProjectDirs::new().expect("Could not get home directory"));
+pub static PROJECT_DIRS: LazyLock<BatProjectDirs> =
+    LazyLock::new(|| BatProjectDirs::new().expect("Could not get home directory"));

src/syntax_mapping.rs

@@ -2,13 +2,12 @@ use std::{
     path::Path,
     sync::{
         atomic::{AtomicBool, Ordering},
-        Arc,
+        Arc, LazyLock,
     },
     thread,
 };
 
 use globset::{Candidate, GlobBuilder, GlobMatcher};
-use once_cell::sync::Lazy;
 
 use crate::error::Result;
 use builtin::BUILTIN_MAPPINGS;
@@ -93,7 +92,7 @@ impl<'a> SyntaxMapping<'a> {
                 if halt.load(Ordering::Relaxed) {
                     break;
                 }
-                Lazy::force(matcher);
+                LazyLock::force(matcher);
             }
         });
         // Note that this thread is not joined upon completion because there's

src/syntax_mapping/builtin.rs

@@ -1,7 +1,6 @@
-use std::env;
+use std::{env, sync::LazyLock};
 
 use globset::GlobMatcher;
-use once_cell::sync::Lazy;
 
 use crate::syntax_mapping::{make_glob_matcher, Case, MappingTarget};
 
@@ -22,7 +21,7 @@ include!(concat!(
 // ```
 // enum BuiltinMatcher {
 //     Fixed(&'static str),
-//     Dynamic(Lazy<Option<String>>),
+//     Dynamic(LazyLock<Option<String>>),
 // }
 // ```
 //
@@ -34,7 +33,7 @@ include!(concat!(
 // implementing the lazy matcher compilation logic, I realised that it's most
 // convenient for `BUILTIN_MAPPINGS` to have the following type:
 //
-// `[(Lazy<Option<GlobMatcher>>, MappingTarget); N]`
+// `[(LazyLock<Option<GlobMatcher>>, MappingTarget); N]`
 //
 // The benefit for this is that operations like listing all builtin mappings
 // would be effectively memoised. The caller would not have to compile another
@@ -52,7 +51,7 @@ include!(concat!(
 ///
 /// A failure to compile is a fatal error.
 ///
-/// Used internally by `Lazy<Option<GlobMatcher>>`'s lazy evaluation closure.
+/// Used internally by `LazyLock<Option<GlobMatcher>>`'s lazy evaluation closure.
 fn build_matcher_fixed(from: &str, case: Case) -> GlobMatcher {
     make_glob_matcher(from, case).expect("A builtin fixed glob matcher failed to compile")
 }
@@ -63,7 +62,7 @@ fn build_matcher_fixed(from: &str, case: Case) -> GlobMatcher {
 /// Returns `None` if any replacement fails, or if the joined glob string fails
 /// to compile.
 ///
-/// Used internally by `Lazy<Option<GlobMatcher>>`'s lazy evaluation closure.
+/// Used internally by `LazyLock<Option<GlobMatcher>>`'s lazy evaluation closure.
 fn build_matcher_dynamic(segs: &[MatcherSegment], case: Case) -> Option<GlobMatcher> {
     // join segments
     let mut buf = String::new();
@@ -83,7 +82,7 @@ fn build_matcher_dynamic(segs: &[MatcherSegment], case: Case) -> Option<GlobMatc
 
 /// A segment of a dynamic builtin matcher.
 ///
-/// Used internally by `Lazy<Option<GlobMatcher>>`'s lazy evaluation closure.
+/// Used internally by `LazyLock<Option<GlobMatcher>>`'s lazy evaluation closure.
 #[derive(Clone, Debug)]
 enum MatcherSegment {
     Text(&'static str),