fix: get_locale follows posix standard

CHANGELOG.md

@@ -16,6 +16,7 @@ All notable changes to eww will be listed here, starting at changes since versio
 - Fix values in the `EWW_NET` variable (By: mario-kr)
 - Fix the gtk `expander` widget (By: ovalkonia)
 - Fix wayland monitor names support (By: dragonnn)
+- `get_locale` now follows POSIX standard for locale selection (By: mirhahn, w-lfchen)
 
 ### Features
 - Add OnDemand support for focusable on wayland (By: GallowsDove)

crates/eww_shared_util/src/locale.rs

@@ -1,14 +1,12 @@
 use chrono::Locale;
 use std::env::var;
 
-/// Returns the `Locale` enum based on the `LC_TIME` environment variable.
+/// Returns the `Locale` enum based on the `LC_ALL`, `LC_TIME`, and `LANG` environment variables in
+/// that order, which is the precedence order prescribed by Section 8.2 of POSIX.1-2017.
 /// If the environment variable is not defined or is malformed use the POSIX locale.
 pub fn get_locale() -> Locale {
-    let locale_string: String =
-        var("LC_TIME").map_or_else(|_| "C".to_string(), |v| v.split(".").next().unwrap_or("C").to_string());
-
-    match (&*locale_string).try_into() {
-        Ok(x) => x,
-        Err(_) => Locale::POSIX,
-    }
+    var("LC_ALL")
+        .or_else(|_| var("LC_TIME"))
+        .or_else(|_| var("LANG"))
+        .map_or(Locale::POSIX, |v| v.split('.').next().and_then(|x| x.try_into().ok()).unwrap_or_default())
 }