Improve name:latin logic

planetiler-basemap/src/main/java/com/onthegomap/planetiler/basemap/util/LanguageUtils.java

@@ -42,6 +42,7 @@ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.Predicate;
 import java.util.regex.Pattern;
 import java.util.stream.Stream;
 
@@ -53,10 +54,23 @@ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * <a href="https://github.com/openmaptiles/openmaptiles-tools/blob/master/sql/zzz_language.sql">openmaptiles-tools</a>.
  */
 public class LanguageUtils {
+  // See https://github.com/onthegomap/planetiler/issues/86
+
+  // Name tags that should be eligible for finding a latin name.
+  // See https://wiki.openstreetmap.org/wiki/Multilingual_names
+  private static final Predicate<String> VALID_NAME_TAGS =
+    Pattern
+      .compile("^name:[a-z]{2,3}(-[a-z]{4})?([-_](x-)?[a-z]{2,})?(-([a-z]{2}|[0-9]{3}))?$", Pattern.CASE_INSENSITIVE)
+      .asMatchPredicate();
+
+  // Match strings that only contain latin characters.
+  private static final Predicate<String> ONLY_LATIN = Pattern
+    .compile("^[\\P{IsLetter}[\\p{IsLetter}&&\\p{IsLatin}]]+$")
+    .asMatchPredicate();
+
+  // Match only latin letters
+  private static final Pattern LATIN_LETTER = Pattern.compile("[\\p{IsLetter}&&\\p{IsLatin}]+");
 
-  private static final Pattern NONLATIN = Pattern
-    .compile("[^\\x{0000}-\\x{024f}\\x{1E00}-\\x{1EFF}\\x{0300}-\\x{036f}\\x{0259}]");
-  private static final Pattern LETTER = Pattern.compile("[A-Za-zÀ-ÖØ-öø-ÿĀ-ɏ]+");
   private static final Pattern EMPTY_PARENS = Pattern.compile("(\\([ -.]*\\)|\\[[ -.]*])");
   private static final Pattern LEADING_TRAILING_JUNK = Pattern.compile("(^\\s*([./-]\\s*)*|(\\s+[./-])*\\s*$)");
   private static final Pattern WHITESPACE = Pattern.compile("\\s+");
@@ -73,7 +87,7 @@ private static String string(Object obj) {
   }
 
   static boolean containsOnlyLatinCharacters(String string) {
-    return string != null && !NONLATIN.matcher(string).find();
+    return string != null && ONLY_LATIN.test(string);
   }
 
   private static String transliteratedName(Map<String, Object> tags) {
@@ -84,7 +98,7 @@ static String removeLatinCharacters(String name) {
     if (name == null) {
       return null;
     }
-    var matcher = LETTER.matcher(name);
+    var matcher = LATIN_LETTER.matcher(name);
     if (matcher.find()) {
       String result = matcher.replaceAll("");
       // if the name was "<nonlatin text> (<latin description)"
@@ -128,7 +142,8 @@ public static Map<String, Object> getNames(Map<String, Object> tags, Translation
 
     boolean isLatin = containsOnlyLatinCharacters(name);
     String latin = isLatin ? name :
-      Stream.concat(Stream.of(nameEn, intName, nameDe), getAllNameTranslationsBesidesEnglishAndGerman(tags))
+      Stream
+        .concat(Stream.of(nameEn, intName, nameDe), getAllNameTranslationsBesidesEnglishAndGerman(tags))
         .filter(LanguageUtils::containsOnlyLatinCharacters)
         .findFirst().orElse(null);
     if (latin == null && translations != null && translations.getShouldTransliterate()) {
@@ -160,12 +175,8 @@ public static Map<String, Object> getNames(Map<String, Object> tags, Translation
 
   private static Stream<String> getAllNameTranslationsBesidesEnglishAndGerman(Map<String, Object> tags) {
     return tags.entrySet().stream()
-      .filter(e -> {
-        String key = e.getKey();
-        return key.startsWith("name:") && !EN_DE_NAME_KEYS.contains(key);
-      })
+      .filter(e -> !EN_DE_NAME_KEYS.contains(e.getKey()) && VALID_NAME_TAGS.test(e.getKey()))
       .map(Map.Entry::getValue)
       .map(LanguageUtils::string);
   }
-
 }

planetiler-basemap/src/test/java/com/onthegomap/planetiler/basemap/util/LanguageUtilsTest.java

@@ -13,6 +13,7 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.CsvSource;
+import org.junit.jupiter.params.provider.ValueSource;
 
 public class LanguageUtilsTest {
 
@@ -59,7 +60,7 @@ public void testSimpleExample() {
     "é, true",
     "éś, true",
     "ɏə, true",
-    "ɐ, false",
+    "ɐ, true",
     "ᵿἀ, false",
     "Ḁỿ, true",
     "\u02ff\u0370, false",
@@ -95,26 +96,97 @@ public void testRemoveNonLatin(String in, String out) {
   }
 
   @ParameterizedTest
-  @CsvSource({
-    "name, a, true",
-    "name:en, a, true",
-    "int_name, a, true",
-    "name:fr, a, true",
-    "name:es, a, true",
-    "name:pt, a, true",
-    "name:de, a, true",
-    "name:ar, ِغَّ, false",
-    "name:it, a, true",
-    "name:jp, ア, false",
-    "name:jp-Latn, a, true",
-    "name:jp_rm, a, true",
+  @ValueSource(strings = {
+    // OSM tags that SHOULD be eligible for name:latin feature in the output
+    "name:en",
+    "name:en-US",
+    "name:en-010",
+    "int_name",
+    "name:fr",
+    "name:es",
+    "name:pt",
+    "name:de",
+    "name:ar",
+    "name:it",
+    "name:ko-Latn",
+    "name:be-tarask",
+    // https://wiki.openstreetmap.org/wiki/Multilingual_names#Japan
+    "name:ja",
+    "name:ja-Latn",
+    "name:ja_rm",
+    "name:ja_kana",
+    // https://wiki.openstreetmap.org/wiki/Multilingual_names#China
+    "name:zh-CN",
+    "name:zh-hant-CN",
+    "name:zh_pinyin",
+    "name:zh_zhuyin",
+    "name:zh-Latn-tongyong",
+    "name:zh-Latn-pinyin",
+    "name:zh-Latn-wadegiles",
+    "name:yue-Latn-jyutping",
+    // https://wiki.openstreetmap.org/wiki/Multilingual_names#France
+    "name:fr",
+    "name:fr-x-gallo",
+    "name:br",
+    "name:oc",
+    "name:vls",
+    "name:frp",
+    "name:gcf",
+    "name:gsw",
   })
-  public void testLatinFallbacks(String key, String value, boolean use) {
-    assertEquals(use ? value : null, LanguageUtils.getNames(Map.of(
-      key, value
+  public void testLatinFallbacks(String key) {
+    assertEquals("a", LanguageUtils.getNames(Map.of(
+      key, "a"
+    ), translations).get("name:latin"));
+    assertNull(LanguageUtils.getNames(Map.of(
+      key, "ア"
+    ), translations).get("name:latin"));
+    assertNull(LanguageUtils.getNames(Map.of(
+      key, "غ"
     ), translations).get("name:latin"));
   }
 
+  @ParameterizedTest
+  @ValueSource(strings = {
+    // OSM tags that should NOT be eligible for name:latin feature in the output
+    "name:signed",
+    "name:prefix",
+    "name:abbreviation",
+    "name:source",
+    "name:full",
+    "name:adjective",
+    "name:proposed",
+    "name:pronunciation",
+    "name:etymology",
+    "name:etymology:wikidata",
+    "name:etymology:wikipedia",
+    "name:etymology:right",
+    "name:etymology:left",
+    "name:genitive",
+  })
+  public void testNoLatinFallback(String key) {
+    assertSubmap(Map.of(
+      "name", "Branch Hill–Loveland Road",
+      "name_en", "Branch Hill–Loveland Road",
+      "name_de", "Branch Hill–Loveland Road",
+      "name:latin", "Branch Hill–Loveland Road",
+      "name_int", "Branch Hill–Loveland Road"
+    ), LanguageUtils.getNames(Map.of(
+      "name", "Branch Hill–Loveland Road",
+      key, "Q22133584;Q843993"
+    ), translations));
+    assertSubmap(Map.of(
+      "name", "日",
+      "name_en", "日",
+      "name_de", "日",
+      "name:latin", "rì",
+      "name_int", "rì"
+    ), LanguageUtils.getNames(Map.of(
+      "name", "日",
+      key, "other" // don't use this latin string with invalid name keys
+    ), translations));
+  }
+
   @ParameterizedTest
   @CsvSource({
     "キャンパス, kyanpasu",

planetiler-core/src/main/java/com/onthegomap/planetiler/util/Translations.java

@@ -88,6 +88,10 @@ public Translations setShouldTransliterate(boolean shouldTransliterate) {
     return this;
   }
 
+  /** Returns true if {@code language} is in the set of language translations to use. */
+  public boolean careAboutLanguage(String language) {
+    return languageSet.contains(language);
+  }
 
   /** A source of name translations. */
   public interface TranslationProvider {