Use once_cell instead of lazy_static

once_cell can do what lazy_static does and more, so replace lazy_static with
once_cell.

See https://docs.rs/once_cell/1.8.0/once_cell/#general-purpose-lazy-evaluation

Cargo.toml

@@ -27,7 +27,6 @@ minimal-application = [
     "atty",
     "clap",
     "dirs-next",
-    "lazy_static",
     "paging",
     "regex-onig",
     "wild",
@@ -48,7 +47,6 @@ ansi_colours = "^1.0"
 bincode = "1.0"
 console = "0.15.0"
 flate2 = "1.0"
-lazy_static = { version = "1.4", optional = true }
 once_cell = "1.8"
 thiserror = "1.0"
 wild = { version = "2.0", optional = true }

src/bin/bat/clap_app.rs

@@ -1,21 +1,20 @@
 use clap::{crate_name, crate_version, App as ClapApp, AppSettings, Arg, ArgGroup, SubCommand};
+use once_cell::sync::Lazy;
 use std::env;
 use std::path::Path;
 
-lazy_static::lazy_static! {
-    static ref VERSION: String = {
-        #[cfg(feature = "bugreport")]
-        let git_version = bugreport::git_version!(fallback = "");
-        #[cfg(not(feature = "bugreport"))]
-        let git_version = "";
+static VERSION: Lazy<String> = Lazy::new(|| {
+    #[cfg(feature = "bugreport")]
+    let git_version = bugreport::git_version!(fallback = "");
+    #[cfg(not(feature = "bugreport"))]
+    let git_version = "";
 
-        if git_version.is_empty() {
-            crate_version!().to_string()
-        } else {
-            format!("{} ({})", crate_version!(), git_version)
-        }
-    };
-}
+    if git_version.is_empty() {
+        crate_version!().to_string()
+    } else {
+        format!("{} ({})", crate_version!(), git_version)
+    }
+});
 
 pub fn build_app(interactive_output: bool) -> ClapApp<'static, 'static> {
     let clap_color_setting = if interactive_output && env::var_os("NO_COLOR").is_none() {

src/bin/bat/directories.rs

@@ -1,7 +1,7 @@
 use std::env;
 use std::path::{Path, PathBuf};
 
-use lazy_static::lazy_static;
+use once_cell::sync::Lazy;
 
 /// Wrapper for 'dirs' that treats MacOS more like Linux, by following the XDG specification.
 /// The `XDG_CACHE_HOME` environment variable is checked first. `BAT_CONFIG_DIR`
@@ -68,7 +68,5 @@ impl BatProjectDirs {
     }
 }
 
-lazy_static! {
-    pub static ref PROJECT_DIRS: BatProjectDirs =
-        BatProjectDirs::new().expect("Could not get home directory");
-}
+pub static PROJECT_DIRS: Lazy<BatProjectDirs> =
+    Lazy::new(|| BatProjectDirs::new().expect("Could not get home directory"));