Support XDG convention in MacOS too (#1143)

* feat(macos): Support XDG conventions on macOS too

* store base strategy in FnmConfig

* add changeset

---------

Co-authored-by: Utkarsh Gupta <utkarshgupta137@gmail.com>

.changeset/cold-drinks-camp.md

@@ -0,0 +1,5 @@
+---
+"fnm": minor
+---
+
+use XDG conventions in MacOS directories by default

Cargo.lock

@@ -512,27 +512,6 @@ dependencies = [
  "subtle",
 ]
 
-[[package]]
-name = "dirs"
-version = "5.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "44c45a9d03d6676652bcb5e724c7e988de1acad23a711b5217ab9cbecbec2225"
-dependencies = [
- "dirs-sys",
-]
-
-[[package]]
-name = "dirs-sys"
-version = "0.4.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "520f05a5cbd335fae5a99ff7a6ab8627577660ee5cfd6a94a6a929b52ff0321c"
-dependencies = [
- "libc",
- "option-ext",
- "redox_users",
- "windows-sys 0.48.0",
-]
-
 [[package]]
 name = "displaydoc"
 version = "0.2.4"
@@ -639,6 +618,17 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "etcetera"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "136d1b5283a1ab77bd9257427ffd09d8667ced0570b6f938942bc7568ed5b943"
+dependencies = [
+ "cfg-if",
+ "home",
+ "windows-sys 0.48.0",
+]
+
 [[package]]
 name = "fastrand"
 version = "2.1.0"
@@ -677,11 +667,11 @@ dependencies = [
  "clap_complete",
  "colored",
  "csv",
- "dirs",
  "duct",
  "embed-resource",
  "encoding_rs_io",
  "env_logger",
+ "etcetera",
  "http",
  "indicatif",
  "indoc",
@@ -821,6 +811,15 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "home"
+version = "0.5.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3d1354bf6b7235cb4a0576c2619fd4ed18183f689b12b006a0ee7329eeff9a5"
+dependencies = [
+ "windows-sys 0.52.0",
+]
+
 [[package]]
 name = "http"
 version = "1.1.0"
@@ -1039,16 +1038,6 @@ version = "0.2.155"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "97b3888a4aecf77e811145cadf6eef5901f4782c53886191b2f693f24761847c"
 
-[[package]]
-name = "libredox"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c0ff37bd590ca25063e35af745c343cb7a0271906fb7b37e4813e8f79f00268d"
-dependencies = [
- "bitflags 2.5.0",
- "libc",
-]
-
 [[package]]
 name = "linux-raw-sys"
 version = "0.4.14"
@@ -1252,12 +1241,6 @@ version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ff011a302c396a5197692431fc1948019154afc178baf7d8e37367442a4601cf"
 
-[[package]]
-name = "option-ext"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "04744f49eae99ab78e0d5c0b603ab218f515ea8cfe5a456d7629ad883a3b6e7d"
-
 [[package]]
 name = "os_pipe"
 version = "1.1.5"
@@ -1433,17 +1416,6 @@ dependencies = [
  "bitflags 1.3.2",
 ]
 
-[[package]]
-name = "redox_users"
-version = "0.4.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bd283d9651eeda4b2a83a43c1c91b266c40fd76ecd39a50a8c630ae69dc72891"
-dependencies = [
- "getrandom",
- "libredox",
- "thiserror",
-]
-
 [[package]]
 name = "regex"
 version = "1.10.4"

Cargo.toml

@@ -16,7 +16,7 @@ chrono = { version = "0.4.38", features = ["serde", "now"], default-features = f
 tar = "0.4.40"
 xz2 = "0.1.7"
 node-semver = "2.1.0"
-dirs = "5.0.1"
+etcetera = "0.8.0"
 colored = "2.1.0"
 zip = "2.1.0"
 tempfile = "3.10.1"

src/commands/env.rs

@@ -1,6 +1,5 @@
 use super::command::Command;
 use crate::config::FnmConfig;
-use crate::directories;
 use crate::fs::symlink_dir;
 use crate::outln;
 use crate::path_ext::PathExt;
@@ -36,7 +35,7 @@ fn generate_symlink_path() -> String {
 }
 
 fn make_symlink(config: &FnmConfig) -> Result<std::path::PathBuf, Error> {
-    let base_dir = directories::multishell_storage().ensure_exists_silently();
+    let base_dir = config.multishell_storage().ensure_exists_silently();
     let mut temp_dir = base_dir.join(generate_symlink_path());
 
     while temp_dir.exists() {

src/config.rs

@@ -1,8 +1,8 @@
 use crate::arch::Arch;
+use crate::directories::Directories;
 use crate::log_level::LogLevel;
 use crate::path_ext::PathExt;
 use crate::version_file_strategy::VersionFileStrategy;
-use dirs::{data_dir, home_dir};
 use url::Url;
 
 #[derive(clap::Parser, Debug)]
@@ -87,6 +87,9 @@ pub struct FnmConfig {
         verbatim_doc_comment
     )]
     resolve_engines: bool,
+
+    #[clap(skip)]
+    directories: Directories,
 }
 
 impl Default for FnmConfig {
@@ -100,6 +103,7 @@ impl Default for FnmConfig {
             version_file_strategy: VersionFileStrategy::default(),
             corepack_enabled: false,
             resolve_engines: false,
+            directories: Directories::default(),
         }
     }
 }
@@ -134,19 +138,7 @@ impl FnmConfig {
             return dir;
         }
 
-        let legacy = home_dir()
+        self.directories.default_base_dir()
-            .map(|dir| dir.join(".fnm"))
-            .filter(|dir| dir.exists());
-
-        let modern = data_dir().map(|dir| dir.join("fnm"));
-
-        if let Some(dir) = legacy {
-            return dir;
-        }
-
-        modern
-            .expect("Can't get data directory")
-            .ensure_exists_silently()
     }
 
     pub fn installations_dir(&self) -> std::path::PathBuf {
@@ -165,6 +157,10 @@ impl FnmConfig {
             .ensure_exists_silently()
     }
 
+    pub fn multishell_storage(&self) -> std::path::PathBuf {
+        self.directories.multishell_storage()
+    }
+
     #[cfg(test)]
     pub fn with_base_dir(mut self, base_dir: Option<std::path::PathBuf>) -> Self {
         self.base_dir = base_dir;

src/directories.rs

@@ -1,26 +1,78 @@
+use etcetera::BaseStrategy;
 use std::path::PathBuf;
 
+use crate::path_ext::PathExt;
+
 fn xdg_dir(env: &str) -> Option<PathBuf> {
-    let env_var = std::env::var(env).ok()?;
+    if cfg!(windows) {
-    Some(PathBuf::from(env_var))
+        let env_var = std::env::var(env).ok()?;
+        Some(PathBuf::from(env_var))
+    } else {
+        // On non-Windows platforms, `etcetera` already handles XDG variables
+        None
+    }
 }
 
-fn state_dir() -> Option<PathBuf> {
+fn runtime_dir(basedirs: &impl BaseStrategy) -> Option<PathBuf> {
-    xdg_dir("XDG_STATE_HOME").or_else(dirs::state_dir)
+    xdg_dir("XDG_RUNTIME_DIR").or_else(|| basedirs.runtime_dir())
 }
 
-fn cache_dir() -> Option<PathBuf> {
+fn state_dir(basedirs: &impl BaseStrategy) -> Option<PathBuf> {
-    xdg_dir("XDG_CACHE_HOME").or_else(dirs::cache_dir)
+    xdg_dir("XDG_STATE_HOME").or_else(|| basedirs.state_dir())
 }
 
-fn runtime_dir() -> Option<PathBuf> {
+fn cache_dir(basedirs: &impl BaseStrategy) -> PathBuf {
-    xdg_dir("XDG_RUNTIME_DIR").or_else(dirs::runtime_dir)
+    xdg_dir("XDG_CACHE_HOME").unwrap_or_else(|| basedirs.cache_dir())
 }
 
-pub fn multishell_storage() -> PathBuf {
+/// A helper struct for directories in fnm that uses XDG Base Directory Specification
-    runtime_dir()
+/// if applicable for the platform.
-        .or_else(state_dir)
+#[derive(Debug)]
-        .or_else(cache_dir)
+pub struct Directories(
-        .unwrap_or_else(std::env::temp_dir)
+    #[cfg(windows)] etcetera::base_strategy::Windows,
-        .join("fnm_multishells")
+    #[cfg(not(windows))] etcetera::base_strategy::Xdg,
+);
+
+impl Default for Directories {
+    fn default() -> Self {
+        Self(etcetera::choose_base_strategy().expect("choosing base strategy"))
+    }
+}
+
+impl Directories {
+    pub fn strategy(&self) -> &impl BaseStrategy {
+        &self.0
+    }
+
+    pub fn default_base_dir(&self) -> PathBuf {
+        let strategy = self.strategy();
+        let modern = strategy.data_dir().join("fnm");
+        if modern.exists() {
+            return modern;
+        }
+
+        let legacy = strategy.home_dir().join(".fnm");
+        if legacy.exists() {
+            return legacy;
+        }
+
+        #[cfg(target_os = "macos")]
+        {
+            let basedirs = etcetera::base_strategy::Apple::new().expect("Can't get home directory");
+            let legacy = basedirs.data_dir().join("fnm");
+            if legacy.exists() {
+                return legacy;
+            }
+        }
+
+        modern.ensure_exists_silently()
+    }
+
+    pub fn multishell_storage(&self) -> PathBuf {
+        let basedirs = self.strategy();
+        let dir = runtime_dir(basedirs)
+            .or_else(|| state_dir(basedirs))
+            .unwrap_or_else(|| cache_dir(basedirs));
+        dir.join("fnm_multishells")
+    }
 }