fix(spm): git proxy config (#3264)

Fixes #3263

src/backend/spm.rs

@@ -3,15 +3,14 @@ use crate::backend::Backend;
 use crate::cli::args::BackendArg;
 use crate::cmd::CmdLineRunner;
 use crate::config::Settings;
+use crate::git::Git;
 use crate::install_context::InstallContext;
 use crate::toolset::ToolVersion;
 use crate::{file, github};
 use eyre::WrapErr;
-use git2::Repository;
 use serde::de::{MapAccess, Visitor};
 use serde::Deserializer;
 use serde_derive::Deserialize;
-use std::env::temp_dir;
 use std::fmt::{self, Debug};
 use std::path::PathBuf;
 use url::Url;
@@ -62,7 +61,7 @@ impl Backend for SPMBackend {
         } else {
             tv.version.clone()
         };
-        let repo_dir = self.clone_package_repo(&repo, &revision)?;
+        let repo_dir = self.clone_package_repo(ctx, &tv, &repo, &revision)?;
 
         let executables = self.get_executable_names(&repo_dir)?;
         if executables.is_empty() {
@@ -88,24 +87,24 @@ impl SPMBackend {
 
     fn clone_package_repo(
         &self,
+        ctx: &InstallContext,
+        tv: &ToolVersion,
         package_repo: &SwiftPackageRepo,
         revision: &str,
     ) -> Result<PathBuf, eyre::Error> {
-        let tmp_repo_dir = temp_dir().join("spm").join(package_repo.dir_name(revision));
-        file::remove_all(&tmp_repo_dir)?;
-        file::create_dir_all(tmp_repo_dir.parent().unwrap())?;
+        let repo = Git::new(tv.cache_path().join(package_repo.dir_name(revision)));
+        if !repo.exists() {
+            debug!(
+                "Cloning swift package repo {} to {}",
+                package_repo.url.as_str(),
+                repo.dir.display(),
+            );
+            repo.clone(package_repo.url.as_str(), Some(ctx.pr.as_ref()))?;
+        }
+        debug!("Checking out revision: {revision}");
+        repo.update(Some(revision.to_string()))?;
 
-        debug!(
-            "Cloning swift package repo: {}, revision: {} to path: {}",
-            package_repo.url.as_str(),
-            revision,
-            tmp_repo_dir.display()
-        );
-        let repo = Repository::clone(package_repo.url.as_str(), &tmp_repo_dir)?;
-        let (object, reference) = repo.revparse_ext(revision)?;
-        repo.checkout_tree(&object, None)?;
-        repo.set_head(reference.unwrap().name().unwrap())?;
-        Ok(tmp_repo_dir)
+        Ok(repo.dir)
     }
 
     fn get_executable_names(&self, repo_dir: &PathBuf) -> Result<Vec<String>, eyre::Error> {

src/git.rs

@@ -67,6 +67,22 @@ impl Git {
     pub fn update(&self, gitref: Option<String>) -> Result<(String, String)> {
         let gitref = gitref.map_or_else(|| self.current_branch(), Ok)?;
         debug!("updating {} to {}", self.dir.display(), gitref);
+        if SETTINGS.libgit2 {
+            if let Ok(repo) = self.repo() {
+                let mut fetch_options = get_fetch_options()?;
+                let mut remote = repo.find_remote("origin")?;
+                remote.fetch(&[&gitref], Some(&mut fetch_options), None)?;
+                let prev_rev = self.current_sha()?;
+                let (obj, reference) = repo.revparse_ext(&gitref)?;
+                repo.checkout_tree(&obj, None)?;
+                if let Some(reference) = reference.and_then(|r| r.name().map(|s| s.to_string())) {
+                    repo.set_head(&reference)?;
+                }
+                let post_rev = self.current_sha()?;
+                touch_dir(&self.dir)?;
+                return Ok((prev_rev, post_rev));
+            }
+        }
         let exec = |cmd: Expression| match cmd.stderr_to_stdout().stdout_capture().unchecked().run()
         {
             Ok(res) => {
@@ -81,6 +97,7 @@ impl Git {
             }
             Err(err) => Err(eyre!("git failed: {cmd:?} {err:#}")),
         };
+        debug!("updating {} to {} with git", self.dir.display(), gitref);
         exec(git_cmd!(
             &self.dir,
             "fetch",