From 21eac33e1f6f7b3c205d3be8c707160125e28ec3 Mon Sep 17 00:00:00 2001
From: Jiahao XU <Jiahao_XU@outlook.com>
Date: Thu, 21 Jul 2022 13:13:07 +1000
Subject: [PATCH] Optimize: Create new fn `helpers::cargo_home`

that caches return value of `home::cargo_home`

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>
---
 src/helpers.rs      | 10 ++++++++++
 src/metafiles/v1.rs |  3 ++-
 src/metafiles/v2.rs |  3 ++-
 3 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/helpers.rs b/src/helpers.rs
index 3dc2de96..3381c839 100644
--- a/src/helpers.rs
+++ b/src/helpers.rs
@@ -1,12 +1,14 @@
 use std::fmt::Debug;
 use std::fs;
 use std::io;
+use std::ops;
 use std::path::{Path, PathBuf};
 
 use bytes::Bytes;
 use cargo_toml::Manifest;
 use futures_util::stream::Stream;
 use log::debug;
+use once_cell::sync::OnceCell;
 use reqwest::{tls, Client, ClientBuilder, Method, Response};
 use serde::Serialize;
 use tempfile::NamedTempFile;
@@ -40,6 +42,14 @@ pub use tls_version::TLSVersion;
 mod crate_name;
 pub use crate_name::CrateName;
 
+pub fn cargo_home() -> Result<&'static Path, io::Error> {
+    static CARGO_HOME: OnceCell<PathBuf> = OnceCell::new();
+
+    CARGO_HOME
+        .get_or_try_init(home::cargo_home)
+        .map(ops::Deref::deref)
+}
+
 pub async fn await_task<T>(task: tokio::task::JoinHandle<miette::Result<T>>) -> miette::Result<T> {
     match task.await {
         Ok(res) => res,
diff --git a/src/metafiles/v1.rs b/src/metafiles/v1.rs
index 1180814a..19f0ab8f 100644
--- a/src/metafiles/v1.rs
+++ b/src/metafiles/v1.rs
@@ -10,6 +10,7 @@ use serde::{Deserialize, Serialize};
 use thiserror::Error;
 
 use super::CrateVersionSource;
+use crate::cargo_home;
 
 #[derive(Clone, Debug, Default, Deserialize, Serialize)]
 pub struct CratesToml {
@@ -18,7 +19,7 @@ pub struct CratesToml {
 
 impl CratesToml {
     pub fn default_path() -> Result<PathBuf, CratesTomlParseError> {
-        Ok(home::cargo_home()?.join(".crates.toml"))
+        Ok(cargo_home()?.join(".crates.toml"))
     }
 
     pub fn load() -> Result<Self, CratesTomlParseError> {
diff --git a/src/metafiles/v2.rs b/src/metafiles/v2.rs
index 70c4e46e..4724b1e8 100644
--- a/src/metafiles/v2.rs
+++ b/src/metafiles/v2.rs
@@ -9,6 +9,7 @@ use serde::{Deserialize, Serialize};
 use thiserror::Error;
 
 use super::CrateVersionSource;
+use crate::cargo_home;
 
 #[derive(Clone, Debug, Default, Deserialize, Serialize)]
 pub struct Crates2Json {
@@ -39,7 +40,7 @@ pub struct CrateInfo {
 
 impl Crates2Json {
     pub fn default_path() -> Result<PathBuf, Crates2JsonParseError> {
-        Ok(home::cargo_home()?.join(".crates2.json"))
+        Ok(cargo_home()?.join(".crates2.json"))
     }
 
     pub fn load() -> Result<Self, Crates2JsonParseError> {