From eeec8d323894d9015b586a94db7497c2080be8c2 Mon Sep 17 00:00:00 2001
From: Simon Tatham <anakin@pobox.com>
Date: Fri, 5 Jan 2024 23:31:21 +0000
Subject: [PATCH] Clippy fix: borrow the HashMap Entry we want to insert into.

I hadn't known about this method of HashMap at all: you can test
whether a key exists, in such a way that you also get a reference to
the slot you'd want to insert it into if it didn't. Then you don't
need the two hash lookups you would with the more obvious approach of
separately testing for contains_key and then maybe inserting.
---
 src/file.rs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/file.rs b/src/file.rs
index f0beffa..39e5a60 100644
--- a/src/file.rs
+++ b/src/file.rs
@@ -1,7 +1,7 @@
 use itertools::Itertools;
 use regex::Regex;
 use std::cmp::{min, max};
-use std::collections::{HashMap, HashSet};
+use std::collections::{HashMap, HashSet, hash_map};
 
 use super::activity_stack::{
     NonUtilityActivity, UtilityActivity, OverlayActivity,
@@ -346,7 +346,7 @@ impl<Type: FileType, Source: FileDataSource> File<Type, Source> {
     fn ensure_item_rendered(&mut self, index: isize, w: usize) ->
         &Vec<ColouredString>
     {
-        if !self.rendered.contains_key(&index) {
+        if let hash_map::Entry::Vacant(e) = self.rendered.entry(index) {
             let mut lines = Vec::new();
 
             let highlight = match self.ui_mode {
@@ -369,7 +369,7 @@ impl<Type: FileType, Source: FileDataSource> File<Type, Source> {
                 }
             }
 
-            self.rendered.insert(index, lines);
+            e.insert(lines);
         }
 
         self.rendered.get(&index).expect("We just made sure this was present")
-- 
2.30.2