From d0b15f157cc3bd56bcfd93f05ac0cdf2343a6c77 Mon Sep 17 00:00:00 2001
From: GnomedDev <david2005thomas@gmail.com>
Date: Sun, 27 Oct 2024 14:11:20 +0000
Subject: [PATCH] Swap Msrv from Vec to SmallVec

---
 clippy_config/src/lib.rs   | 1 +
 clippy_config/src/msrvs.rs | 9 +++++----
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/clippy_config/src/lib.rs b/clippy_config/src/lib.rs
index 42651521f8d..1c3f32c2514 100644
--- a/clippy_config/src/lib.rs
+++ b/clippy_config/src/lib.rs
@@ -20,6 +20,7 @@
 extern crate rustc_errors;
 extern crate rustc_session;
 extern crate rustc_span;
+extern crate smallvec;
 
 mod conf;
 mod metadata;
diff --git a/clippy_config/src/msrvs.rs b/clippy_config/src/msrvs.rs
index 2f4da4cba3d..b809d8d0487 100644
--- a/clippy_config/src/msrvs.rs
+++ b/clippy_config/src/msrvs.rs
@@ -3,6 +3,7 @@
 use rustc_session::{RustcVersion, Session};
 use rustc_span::{Symbol, sym};
 use serde::Deserialize;
+use smallvec::{SmallVec, smallvec};
 use std::fmt;
 
 macro_rules! msrv_aliases {
@@ -67,7 +68,7 @@ macro_rules! msrv_aliases {
 /// Tracks the current MSRV from `clippy.toml`, `Cargo.toml` or set via `#[clippy::msrv]`
 #[derive(Debug, Clone)]
 pub struct Msrv {
-    stack: Vec<RustcVersion>,
+    stack: SmallVec<[RustcVersion; 2]>,
 }
 
 impl fmt::Display for Msrv {
@@ -87,14 +88,14 @@ fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
     {
         let v = String::deserialize(deserializer)?;
         parse_version(Symbol::intern(&v))
-            .map(|v| Msrv { stack: vec![v] })
+            .map(|v| Msrv { stack: smallvec![v] })
             .ok_or_else(|| serde::de::Error::custom("not a valid Rust version"))
     }
 }
 
 impl Msrv {
     pub fn empty() -> Msrv {
-        Msrv { stack: Vec::new() }
+        Msrv { stack: SmallVec::new() }
     }
 
     pub fn read_cargo(&mut self, sess: &Session) {
@@ -103,7 +104,7 @@ pub fn read_cargo(&mut self, sess: &Session) {
             .and_then(|v| parse_version(Symbol::intern(&v)));
 
         match (self.current(), cargo_msrv) {
-            (None, Some(cargo_msrv)) => self.stack = vec![cargo_msrv],
+            (None, Some(cargo_msrv)) => self.stack = smallvec![cargo_msrv],
             (Some(clippy_msrv), Some(cargo_msrv)) => {
                 if clippy_msrv != cargo_msrv {
                     sess.dcx().warn(format!(