feat(forge): allow install in config folder

cli/src/cmd/forge/install.rs

@@ -63,12 +63,6 @@ impl Cmd for InstallArgs {
         let InstallArgs { root, .. } = self;
         let root = root.unwrap_or_else(|| find_project_root_path().unwrap());
         install(&root, self.dependencies, self.opts)?;
-        let mut config = Config::load_with_root(root);
-        let lib = PathBuf::from("lib");
-        if !config.libs.contains(&lib) {
-            config.libs.push(lib);
-            config.update_libs()?;
-        }
         Ok(())
     }
 }
@@ -90,7 +84,10 @@ pub(crate) fn install(
     opts: DependencyInstallOpts,
 ) -> eyre::Result<()> {
     let root = root.as_ref();
-    let libs = root.join("lib");
+    let mut config = Config::load_with_root(root);
+
+    let install_lib_dir = config.install_lib_dir();
+    let libs = root.join(&install_lib_dir);
 
     if dependencies.is_empty() {
         Command::new("git")
@@ -123,6 +120,12 @@ pub(crate) fn install(
 
         p_println!(!quiet => "    {} {}",    Paint::green("Installed"), dep.name);
     }
+
+    // update `libs` in config if not included yet
+    if !config.libs.contains(&install_lib_dir) {
+        config.libs.push(install_lib_dir);
+        config.update_libs()?;
+    }
     Ok(())
 }
 

config/src/lib.rs

@@ -472,6 +472,17 @@ impl Config {
         self.remappings.dedup();
     }
 
+    /// Returns the directory in which dependencies should be installed
+    ///
+    /// Returns the first dir from `libs` that is not `node_modules` or `lib` if `libs` is empty
+    pub fn install_lib_dir(&self) -> PathBuf {
+        self.libs
+            .iter()
+            .find(|p| !p.ends_with("node_modules"))
+            .map(PathBuf::from)
+            .unwrap_or_else(|| PathBuf::from("lib"))
+    }
+
     /// Serves as the entrypoint for obtaining the project.
     ///
     /// Returns the `Project` configured with all `solc` and path related values.
@@ -2014,6 +2025,35 @@ mod tests {
     use std::{fs::File, io::Write};
     use tempfile::tempdir;
 
+    #[test]
+    fn test_install_dir() {
+        figment::Jail::expect_with(|jail| {
+            let config = Config::load();
+            assert_eq!(config.install_lib_dir(), PathBuf::from("lib"));
+            jail.create_file(
+                "foundry.toml",
+                r#"
+                [default]
+                libs = ['node_modules', 'lib']
+            "#,
+            )?;
+            let config = Config::load();
+            assert_eq!(config.install_lib_dir(), PathBuf::from("lib"));
+
+            jail.create_file(
+                "foundry.toml",
+                r#"
+                [default]
+                libs = ['custom', 'node_modules', 'lib']
+            "#,
+            )?;
+            let config = Config::load();
+            assert_eq!(config.install_lib_dir(), PathBuf::from("custom"));
+
+            Ok(())
+        });
+    }
+
     #[test]
     fn test_figment_is_default() {
         figment::Jail::expect_with(|_| {