ElyTable: a text file's default encoding follows the app's language (T-15)

apps/ely-table/src/tests/output.rs

@@ -469,3 +469,32 @@ fn a_whole_column_print_area_still_applies() {
     let layout = read(&mut cx, &book, sheet::print_layout, sheet::LAYOUT);
     assert!(layout.landscape, "applied with {shown}");
 }
+
+#[test]
+fn the_default_encoding_follows_the_apps_language() {
+    use ely_gpui_component::i18n::I18n;
+    use ely_lok::sheet::csv::Encoding;
+    let dir = tempfile::tempdir().expect("a temp dir");
+    let mut cx = TestAppContext::single();
+    let Some((_window, book)) = book(&mut cx, dir.path()) else {
+        eprintln!("SKIP: no LOK build");
+        return;
+    };
+    let path = dir.path().join("gb.csv");
+    // 你好 in GB18030: not UTF-8.
+    std::fs::write(&path, [0xC4, 0xE3, 0xBA, 0xC3, b'\n']).expect("writes");
+    for (tag, expected) in [("zh-CN", Encoding::Gb18030), ("en-US", Encoding::Windows1252)] {
+        cx.update(|app| I18n::set_locale(tag, app));
+        update(&mut cx, &book, |book, cx| book.ask_import(path.clone(), cx));
+        asked(&cx, &book, |dialog| matches!(dialog, Dialog::Import(_)));
+        let found = cx.update(|app| match book.read(app).dialog.as_ref() {
+            Some(Dialog::Import(pending)) => pending.how.encoding,
+            _ => unreachable!("an import dialog"),
+        });
+        assert_eq!(found, expected, "{tag}");
+        update(&mut cx, &book, |book, cx| {
+            book.dialog = None;
+            cx.notify();
+        });
+    }
+}