fix: lock git dependencies folder when resolving workspace

tooling/nargo_toml/Cargo.toml

@@ -23,6 +23,7 @@ toml.workspace = true
 url.workspace = true
 noirc_driver.workspace = true
 semver = "1.0.20"
+fs2 = "0.4.3"
 
 [dev-dependencies]
 tempfile.workspace = true

tooling/nargo_toml/src/git.rs

@@ -1,4 +1,8 @@
-use std::path::PathBuf;
+use fs2::FileExt;
+use std::{
+    fs::{File, OpenOptions},
+    path::PathBuf,
+};
 
 /// Creates a unique folder name for a GitHub repo
 /// by using its URL and tag
@@ -23,6 +27,19 @@ fn git_dep_location(base: &url::Url, tag: &str) -> PathBuf {
     nargo_crates().join(folder_name)
 }
 
+pub(crate) fn lock_git_deps() -> std::io::Result<File> {
+    std::fs::create_dir_all(nargo_crates())?;
+    let file_path = nargo_crates().join(".package-cache");
+    let file = OpenOptions::new().create(true).truncate(true).write(true).open(file_path)?;
+    if file.try_lock_exclusive().is_err() {
+        eprintln!("Waiting for lock on git dependencies cache...");
+    }
+
+    file.lock_exclusive()?;
+
+    Ok(file)
+}
+
 /// XXX: I'd prefer to use a GitHub library however, there
 /// does not seem to be an easy way to download a repo at a specific
 /// tag

tooling/nargo_toml/src/lib.rs

@@ -10,6 +10,7 @@ use std::{
 
 use errors::SemverError;
 use fm::{NormalizePath, FILE_EXTENSION};
+use fs2::FileExt;
 use nargo::{
     package::{Dependency, Package, PackageType},
     workspace::Workspace,
@@ -23,7 +24,7 @@ mod git;
 mod semver;
 
 pub use errors::ManifestError;
-use git::clone_git_repo;
+use git::{clone_git_repo, lock_git_deps};
 
 /// Searches for a `Nargo.toml` file in the current directory and all parent directories.
 /// For example, if the current directory is `/workspace/package/src`, then this function
@@ -518,7 +519,10 @@ pub fn resolve_workspace_from_toml(
     current_compiler_version: Option<String>,
 ) -> Result<Workspace, ManifestError> {
     let nargo_toml = read_toml(toml_path)?;
+    let lock = lock_git_deps().expect("Failed to lock git dependencies cache");
     let workspace = toml_to_workspace(nargo_toml, package_selection)?;
+    lock.unlock().expect("Failed to unlock git dependencies cache");
+
     if let Some(current_compiler_version) = current_compiler_version {
         semver::semver_check_workspace(&workspace, current_compiler_version)?;
     }