Cache the Git remote URL to speed up rendering hyperlinks

This commit changes the GitConfig struct to cache the GitRemoteRepo,
which speeds up the rendering of hyperlinks by ~55x.

Fixes #1939

Author: charlievieth

src/features/hyperlinks.rs

@@ -6,7 +6,9 @@ use regex::{Match, Matches, Regex};
 
 use crate::config::Config;
 use crate::features::OptionValueFunction;
-use crate::git_config::{GitConfig, GitRemoteRepo};
+
+#[cfg(test)]
+use crate::git_config::GitConfig;
 
 pub fn make_feature() -> Vec<(String, OptionValueFunction)> {
     builtin_feature!([
@@ -19,18 +21,6 @@ pub fn make_feature() -> Vec<(String, OptionValueFunction)> {
     ])
 }
 
-#[cfg(test)]
-pub fn remote_from_config(_: &Option<&GitConfig>) -> Option<GitRemoteRepo> {
-    Some(GitRemoteRepo::GitHub {
-        slug: "dandavison/delta".to_string(),
-    })
-}
-
-#[cfg(not(test))]
-pub fn remote_from_config(cfg: &Option<&GitConfig>) -> Option<GitRemoteRepo> {
-    cfg.and_then(GitConfig::get_remote_url)
-}
-
 lazy_static! {
     // Commit hashes can be abbreviated to 7 characters, these necessarily become longer
     // when more objects are in a repository.
@@ -80,12 +70,14 @@ pub fn format_commit_line_with_osc8_commit_hyperlink<'a>(
                     .with_input(line, &first_match, &mut matches);
             return Cow::from(result);
         }
-    } else if let Some(repo) = remote_from_config(&config.git_config()) {
-        let mut matches = COMMIT_HASH_REGEX.find_iter(line);
-        if let Some(first_match) = matches.next() {
-            let result = HyperlinkCommits(|commit_hash| repo.format_commit_url(commit_hash))
-                .with_input(line, &first_match, &mut matches);
-            return Cow::from(result);
+    } else if let Some(config) = config.git_config() {
+        if let Some(repo) = config.get_remote_url() {
+            let mut matches = COMMIT_HASH_REGEX.find_iter(line);
+            if let Some(first_match) = matches.next() {
+                let result = HyperlinkCommits(|commit_hash| repo.format_commit_url(commit_hash))
+                    .with_input(line, &first_match, &mut matches);
+                return Cow::from(result);
+            }
         }
     }
     Cow::from(line)

src/git_config/mod.rs

@@ -4,6 +4,7 @@ pub use remote::GitRemoteRepo;
 
 use crate::env::DeltaEnv;
 use regex::Regex;
+use std::cell::OnceCell;
 use std::collections::HashMap;
 use std::path::Path;
 
@@ -14,6 +15,7 @@ pub struct GitConfig {
     config_from_env_var: HashMap<String, String>,
     pub enabled: bool,
     repo: Option<git2::Repository>,
+    remote_url: OnceCell<Option<GitRemoteRepo>>,
     // To make GitConfig cloneable when testing (in turn to make Config cloneable):
     #[cfg(test)]
     path: std::path::PathBuf,
@@ -29,6 +31,7 @@ impl Clone for GitConfig {
             config_from_env_var: self.config_from_env_var.clone(),
             enabled: self.enabled,
             repo: None,
+            remote_url: OnceCell::new(),
             path: self.path.clone(),
         }
     }
@@ -57,6 +60,7 @@ impl GitConfig {
                     config_from_env_var: parse_config_from_env_var(env),
                     repo,
                     enabled: true,
+                    remote_url: OnceCell::new(),
                 })
             }
             None => None,
@@ -76,6 +80,7 @@ impl GitConfig {
             config_from_env_var: HashMap::new(),
             enabled: true,
             repo: None,
+            remote_url: OnceCell::new(),
             path: std::path::PathBuf::from("/invalid_null.git"),
         })
     }
@@ -98,6 +103,7 @@ impl GitConfig {
                     },
                     repo: None,
                     enabled: true,
+                    remote_url: OnceCell::new(),
                     #[cfg(test)]
                     path: path.into(),
                 }
@@ -119,8 +125,13 @@ impl GitConfig {
         }
     }
 
+    #[cfg(test)]
+    fn get_remote_url_impl(&self) -> Option<GitRemoteRepo> {
+        GitRemoteRepo::for_testing()
+    }
+
     #[cfg(not(test))]
-    pub fn get_remote_url(&self) -> Option<GitRemoteRepo> {
+    fn get_remote_url_impl(&self) -> Option<GitRemoteRepo> {
         use std::str::FromStr;
         self.repo
             .as_ref()?
@@ -130,6 +141,10 @@ impl GitConfig {
             .and_then(|url| GitRemoteRepo::from_str(url).ok())
     }
 
+    pub fn get_remote_url(&self) -> &Option<GitRemoteRepo> {
+        self.remote_url.get_or_init(|| self.get_remote_url_impl())
+    }
+
     pub fn for_each<F>(&self, regex: &str, mut f: F)
     where
         F: FnMut(&str, Option<&str>),

src/git_config/remote.rs

@@ -31,6 +31,13 @@ impl GitRemoteRepo {
             }
         }
     }
+
+    #[cfg(test)]
+    pub fn for_testing() -> Option<GitRemoteRepo> {
+        Some(GitRemoteRepo::GitHub {
+            slug: "dandavison/delta".to_string(),
+        })
+    }
 }
 
 lazy_static! {