Add Polish localization (#218)

Register Polish interface localization with catalog provenance, locale fallback and plural-form regressions.

Original contribution by @neronek22.

ATTRIBUTION.md

@@ -62,6 +62,7 @@ Generated-in-code assets are original and have no file to list:
 | Asset | Author | Source | Licence | Notes |
 |---|---|---|---|---|
 | `crates/ui-egui/src/i18n/uk.tsv` | @dmatviichuk | Original Ukrainian translations of CADCraft English strings | MIT OR Apache-2.0 (`LICENSE-MIT`, `LICENSE-APACHE`) | No proprietary localization resources copied |
+| `crates/ui-egui/src/i18n/pl.tsv` | @neronek22 (Echo Rozumu & Gadajło; AI-assisted) | Original Polish translations of CADCraft English strings | MIT OR Apache-2.0 (`LICENSE-MIT`, `LICENSE-APACHE`) | No proprietary localization resources copied |
 | `crates/ui-egui/src/i18n/de.tsv` | the CADCraft contributors | Original German translations of CADCraft English strings | MIT OR Apache-2.0 (`LICENSE-MIT`, `LICENSE-APACHE`) | No proprietary localization resources copied |
 | `crates/ui-egui/src/i18n/es.tsv` | @PedroGuille | Original Spanish translations of CADCraft English strings | MIT OR Apache-2.0 (`LICENSE-MIT`, `LICENSE-APACHE`) | No proprietary localization resources copied |
 | `crates/ui-egui/src/i18n/pt_br.tsv` | @WladmirJunior | Original Brazilian Portuguese translations of CADCraft English strings | MIT OR Apache-2.0 (`LICENSE-MIT`, `LICENSE-APACHE`) | No proprietary localization resources copied |

crates/ui-egui/src/i18n.rs

@@ -19,6 +19,8 @@ pub enum Preference {
     Greek,
     #[serde(rename = "uk")]
     Ukrainian,
+    #[serde(rename = "pl")]
+    Polish,
     #[serde(rename = "pt-BR")]
     BrazilianPortuguese,
     #[serde(rename = "de")]
@@ -52,13 +54,13 @@ pub enum Preference {
     #[serde(rename = "vi")]
     Vietnamese,
 }
-
 impl Preference {
-    pub const ALL: [Self; 20] = [
+    pub const ALL: [Self; 21] = [
         Self::Auto,
         Self::English,
         Self::Greek,
         Self::Ukrainian,
+        Self::Polish,
         Self::BrazilianPortuguese,
         Self::German,
         Self::Spanish,
@@ -109,6 +111,7 @@ impl Preference {
             Self::English => "en",
             Self::Greek => "el",
             Self::Ukrainian => "uk",
+            Self::Polish => "pl",
             Self::BrazilianPortuguese => "pt-BR",
             Self::German => "de",
             Self::Spanish => "es",
@@ -134,6 +137,7 @@ impl Preference {
             Self::English => "English",
             Self::Greek => "Ελληνικά",
             Self::Ukrainian => "Українська",
+            Self::Polish => "Polski",
             Self::BrazilianPortuguese => "Português (Brasil)",
             Self::German => "Deutsch",
             Self::Spanish => "Español",
@@ -188,6 +192,7 @@ impl Preference {
             Self::English => "en",
             Self::Greek => "el",
             Self::Ukrainian => "uk",
+            Self::Polish => "pl",
             Self::BrazilianPortuguese => "pt-BR",
             Self::German => "de",
             Self::Spanish => "es",
@@ -220,8 +225,9 @@ pub struct Language {
     catalog: OnceLock<Catalog<'static>>,
 }
 
-pub static LANGUAGES: [Language; 19] = [
+pub static LANGUAGES: [Language; 20] = [
     Language { code: "en", name: "English", source: "", plural: plural_en, plural_forms: 2, catalog: OnceLock::new() },
+    Language { code: "pl", name: "Polski", source: include_str!("i18n/pl.tsv"), plural: plural_pl, plural_forms: 3, catalog: OnceLock::new() },
     // Greek: one for exactly 1; other for zero and all other integer counts.
     Language {
         code: "el", name: "Ελληνικά", source: include_str!("i18n/el.tsv"), plural: plural_en, plural_forms: 2, catalog: OnceLock::new()
@@ -375,6 +381,17 @@ pub fn format(source: &str, values: &[(&str, String)]) -> String {
     result
 }
 
+/// Polish plurals: one (1), few (2–4, 22–24), many (0, 5–21, 25–31).
+pub fn plural_pl(n: u64) -> usize {
+    if n == 1 {
+        0
+    } else if (2..=4).contains(&(n % 10)) && !(12..=14).contains(&(n % 100)) {
+        1
+    } else {
+        2
+    }
+}
+
 /// Ukrainian integer plurals: one (1, 21), few (2–4, 22–24), many (0, 5–20, 25…).
 pub fn plural_uk(n: u64) -> usize {
     match (n % 10, n % 100) {

crates/ui-egui/src/i18n/tests.rs

@@ -195,12 +195,20 @@ fn assert_primary_locale_aliases() {
     for (tag, code) in [("ru", "ru"), ("ru-RU", "ru"), ("ru_RU.UTF-8", "ru"), ("fr", "fr"), ("fr-FR", "fr"), ("fr_CA.UTF-8", "fr")] {
         assert_eq!(locale_language(tag), Some(code), "{tag}");
     }
+
+    for tag in ["ua", "ukulele", "xx-XX", "", "garbage", "💙"] {
+        assert_eq!(locale_language(tag), None, "{tag}");
+    }
+    assert_eq!(locale_language("pl-PL"), Some("pl"));
+    assert_eq!(Preference::Auto.resolve(&["pl-PL".into(), "pt-BR".into()]), "pl");
+    assert_eq!(Preference::Auto.resolve(&["fr-FR".into(), "pt-BR".into()]), "fr");
 }
 
 fn assert_portuguese_and_spanish_aliases() {
     for tag in ["pt", "pt-BR", "pt_BR.UTF-8", "PT-br", "pt-PT"] {
         assert_eq!(locale_language(tag), Some("pt-BR"), "{tag}");
     }
+
     for tag in ["es", "es-ES", "es_MX.UTF-8", "ES-ar"] {
         assert_eq!(locale_language(tag), Some("es"), "{tag}");
     }
@@ -228,7 +236,7 @@ fn assert_additional_locale_aliases() {
 
 fn assert_unrecognized_locale_tags() {
     // Look-alike codes, three-letter codes and endonyms pick nothing: `se` is Northern Sami.
-    let look_alikes = ["ua", "ukulele", "pl-PL", "", "garbage", "💙", "ptolemy", "cz", "csharp", "csomething", "italic"];
+    let look_alikes = ["ua", "ukulele", "nl-NL", "", "garbage", "💙", "ptolemy", "cz", "csharp", "csomething", "italic"];
     let others = ["kr", "korean", "kotlin", "se", "swe", "svenska", "hun", "magyar", "tur", "türkçe", "elvish", "kat", "geo", "kab", "kartuli"];
     for tag in look_alikes.into_iter().chain(others) {
         assert_eq!(locale_language(tag), None, "{tag}");
@@ -236,10 +244,11 @@ fn assert_unrecognized_locale_tags() {
 }
 
 fn assert_auto_locale_precedence() {
-    assert_eq!(Preference::Auto.resolve(&["pl-PL".into(), "pt-BR".into()]), "pt-BR");
+    assert_eq!(Preference::Auto.resolve(&["nl-NL".into(), "pt-BR".into()]), "pt-BR");
+    assert_eq!(Preference::Auto.resolve(&["pl-PL".into(), "pt-BR".into()]), "pl");
     assert_eq!(Preference::Auto.resolve(&["fr-FR".into(), "pt-BR".into()]), "fr");
     assert_eq!(Preference::Auto.resolve(&["es-ES".into(), "pt-BR".into()]), "es");
-    let locales = vec!["pl-PL".into(), "uk-UA".into(), "en-US".into()];
+    let locales = vec!["nl-NL".into(), "uk-UA".into(), "en-US".into()];
     assert_eq!(Preference::Auto.resolve(&locales), "uk");
     assert_eq!(Preference::English.resolve(&locales), "en");
     assert_eq!(Preference::Auto.resolve(&["en-US".into(), "uk-UA".into()]), "en");
@@ -262,7 +271,7 @@ fn assert_preference_resolution(preference: Preference) {
     // A chosen language wins over the system's; Auto takes the first system language there is.
     assert_eq!(preference.resolve(&["uk-UA".into()]), preference.code());
     if preference != Preference::English {
-        assert_eq!(Preference::Auto.resolve(&["pl-PL".into(), preference.code().into(), "en-US".into()]), preference.code());
+        assert_eq!(Preference::Auto.resolve(&["nl-NL".into(), preference.code().into(), "en-US".into()]), preference.code());
     }
 }
 
@@ -279,6 +288,8 @@ fn assert_saved_preference_persistence(preference: Preference) {
 #[test]
 fn locale_and_saved_preference_resolution() {
     assert_primary_locale_aliases();
+    assert_eq!(locale_language("pl-PL"), Some("pl"));
+    assert_eq!(Preference::parse("pl"), Some(Preference::Polish));
     assert_portuguese_and_spanish_aliases();
     assert_additional_locale_aliases();
     assert_unrecognized_locale_tags();
@@ -668,3 +679,11 @@ fn vietnamese_takes_one_form_and_needs_a_font_with_its_letters() {
         assert_eq!(Preference::Vietnamese.name(), "Vietnamese");
     }
 }
+
+#[test]
+fn polish_plural_forms() {
+    for (n, expected) in [(0, 2), (1, 0), (2, 1), (4, 1), (5, 2), (12, 2), (14, 2), (21, 2), (22, 1), (24, 1), (25, 2), (101, 2), (102, 1), (112, 2)]
+    {
+        assert_eq!(plural_pl(n), expected, "n={n}");
+    }
+}