Support vendor and user completions

crates/nu-path/Cargo.toml

@@ -16,6 +16,8 @@ dirs-next = "2.0"
 
 [target.'cfg(windows)'.dependencies]
 omnipath = "0.1"
+winapi = "0.3"
+dirs-sys-next = "0.1"
 
 [target.'cfg(all(unix, not(target_os = "macos"), not(target_os = "android")))'.dependencies]
 pwd = "1.3"

crates/nu-path/src/helpers.rs

@@ -10,6 +10,42 @@ pub fn config_dir() -> Option<PathBuf> {
     dirs_next::config_dir()
 }
 
+pub fn vendor_completions_dirs() -> Vec<PathBuf> {
+    let vendor_completions_fn = |mut path: PathBuf| {
+        path.push("nushell");
+        path.push("completions");
+        path
+    };
+    let mut dirs = Vec::new();
+
+    // default global directory
+    #[cfg(not(target_os = "windows"))]
+    let global_default = Some(PathBuf::from("/usr/share"));
+    #[cfg(target_os = "windows")]
+    let global_default = dirs_sys_next::known_folder(&winapi::um::knownfolders::FOLDERID_ProgramData);
+
+    // global directory
+    if let Some(global) = std::env::var("NU_VENDOR_COMPLETIONS_DIR")
+        .ok()
+        .or(option_env!("NU_VENDOR_COMPLETIONS_DIR").map(String::from))
+        .map(PathBuf::from)
+        .or(global_default.map(vendor_completions_fn))
+    {
+        dirs.push(global);
+    }
+
+    // local directory of the current user
+    if let Some(data_dir) = std::env::var("NU_COMPLETIONS_DIR")
+        .ok()
+        .map(PathBuf::from)
+        .or_else(|| dirs_next::data_dir().map(vendor_completions_fn))
+    {
+        dirs.push(data_dir);
+    }
+
+    dirs
+}
+
 #[cfg(windows)]
 pub fn canonicalize(path: &std::path::Path) -> std::io::Result<std::path::PathBuf> {
     path.canonicalize()?.to_winuser_path()

crates/nu-path/src/lib.rs

@@ -5,6 +5,6 @@ mod tilde;
 mod util;
 
 pub use expansions::{canonicalize_with, expand_path_with, expand_to_real_path};
-pub use helpers::{config_dir, home_dir};
+pub use helpers::{config_dir, home_dir, vendor_completions_dirs};
 pub use tilde::expand_tilde;
 pub use util::trim_trailing_slash;

crates/nu-utils/src/sample_config/default_env.nu

@@ -85,6 +85,25 @@ $env.ENV_CONVERSIONS = {
     }
 }
 
+# Completions distributed by package managers are sourced from a global vendor
+# completions directory If you want to override the default, you can do so like
+# this:
+#
+# $env.NU_VENDOR_COMPLETIONS_DIR = ...
+#
+# The default is /usr/share/nushell/vendor_completions.d on Linux and MacOS,
+# and %ProgramData%\nushell\vendor_completions.d on Windows
+#
+# There's a similar path for completions installed by the user, which can be
+# overridden like so:
+#
+# $env.NU_COMPLETIONS_DIR = ...
+#
+# The default here is $XDG_DATA_HOME/nushell/vendor_completions.d on Linux,
+# falling back to $HOME/.local/share for $XDG_DATA_HOME if it's not set,
+# $HOME/Library/Application Support/nushell/vendor_completions.d on MacOS,
+# and %RoamingAppData%\nushell\vendor_completions.d on Windows.
+
 # Directories to search for scripts when calling source or use
 # The default for this is $nu.default-config-dir/scripts
 $env.NU_LIB_DIRS = [

src/config_files.rs

@@ -22,6 +22,7 @@ pub(crate) fn read_config_file(
     config_file: Option<Spanned<String>>,
     is_env_config: bool,
 ) {
+    read_vendor_completions(engine_state, stack);
     // Load config startup file
     if let Some(file) = config_file {
         let working_set = StateWorkingSet::new(engine_state);
@@ -123,6 +124,23 @@ pub(crate) fn read_loginshell_file(engine_state: &mut EngineState, stack: &mut S
     info!("read_loginshell_file {}:{}:{}", file!(), line!(), column!());
 }
 
+pub(crate) fn read_vendor_completions(engine_state: &mut EngineState, stack: &mut Stack) {
+    nu_path::vendor_completions_dirs()
+        .into_iter()
+        .filter_map(|dir| dir.read_dir().ok())
+        .flatten()
+        .filter_map(|entry| entry.ok())
+        .map(|entry| entry.path())
+        .filter(|entry| entry.is_file())
+        .filter(|entry| {
+            entry
+                .extension()
+                .filter(|extension| extension.to_str() == Some("nu"))
+                .is_some()
+        })
+        .for_each(|entry| eval_config_contents(entry, engine_state, stack));
+}
+
 pub(crate) fn read_default_env_file(engine_state: &mut EngineState, stack: &mut Stack) {
     let config_file = get_default_env();
     eval_source(