test technical correctness of localization files

main/ui/src/test/java/org/cryptomator/ui/LocalizationTest.java

@@ -0,0 +1,85 @@
+package org.cryptomator.ui;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.Reader;
+import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.PropertyResourceBundle;
+import java.util.ResourceBundle;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class LocalizationTest {
+
+	private static final Logger LOG = LoggerFactory.getLogger(LocalizationTest.class);
+	private static final String RESOURCE_FOLDER_PATH = "/localization/";
+	private static final String REF_FILE_NAME = "en.txt";
+	private static final String[] LANG_FILE_NAMES = {"de.txt", "es.txt", "fr.txt", "hu.txt", "it.txt", "kr.txt", "nl.txt", "pt.txt", "ru.txt", "sk.txt", "tr.txt"};
+
+	/*
+	 * @see Formatter
+	 */
+	private static final String ARG_INDEX_REGEX = "(\\d+\\$)?"; // e.g. %1$s
+	private static final String FLAG_REGEX = "[-#+ 0,\\(]*"; // e.g. %0,f
+	private static final String WIDTH_AND_PRECISION_REGEX = "(\\d*(\\.\\d+))?"; // e.g. %4.2f
+	private static final String GENERAL_CONVERSION_REGEX = "[bBhHsScCdoxXeEfgGaA%n]"; // e.g. %f
+	private static final String TIME_CONVERSION_REGEX = "[tT][HIklMSLNpzZsQBbhAaCYyjmdeRTrDFc]"; // e.g. %1$tY-%1$tm-%1$td
+	private static final String CONVERSION_REGEX = "(" + GENERAL_CONVERSION_REGEX + "|" + TIME_CONVERSION_REGEX + ")";
+	private static final String PLACEHOLDER_REGEX = "%" + ARG_INDEX_REGEX + FLAG_REGEX + WIDTH_AND_PRECISION_REGEX + CONVERSION_REGEX;
+	private static final Pattern PLACEHOLDER_PATTERN = Pattern.compile(PLACEHOLDER_REGEX);
+
+	@Test
+	public void testStringFormatIsValid() throws IOException {
+		ResourceBundle ref = loadLanguage(RESOURCE_FOLDER_PATH + REF_FILE_NAME);
+		boolean allGood = true;
+		for (String langFileName : LANG_FILE_NAMES) {
+			ResourceBundle lang = loadLanguage(RESOURCE_FOLDER_PATH + langFileName);
+			allGood &= allStringFormatSpecifiersMatchReferenceLanguage(ref, lang, langFileName);
+		}
+		Assert.assertTrue(allGood);
+	}
+
+	private boolean allStringFormatSpecifiersMatchReferenceLanguage(ResourceBundle ref, ResourceBundle lang, String langFileName) {
+		boolean allGood = true;
+		for (String key : Collections.list(ref.getKeys())) {
+			if (!lang.containsKey(key)) {
+				continue;
+			}
+			List<String> refPlaceholders = findPlaceholders(ref.getString(key));
+			if (refPlaceholders.isEmpty()) {
+				continue;
+			}
+			List<String> langPlaceholders = findPlaceholders(lang.getString(key));
+			if (!langPlaceholders.containsAll(refPlaceholders) || !refPlaceholders.containsAll(langPlaceholders)) {
+				LOG.warn("Placeholders don't match for term {}. Lang={}, Required={}, Found={}", key, langFileName, refPlaceholders, langPlaceholders);
+				allGood = false;
+			}
+		}
+		return allGood;
+	}
+
+	private List<String> findPlaceholders(String str) {
+		Matcher m = PLACEHOLDER_PATTERN.matcher(str);
+		List<String> placeholders = new ArrayList<>();
+		while (m.find()) {
+			placeholders.add(m.group());
+		}
+		return placeholders;
+	}
+
+	private ResourceBundle loadLanguage(String path) throws IOException {
+		try (InputStream in = getClass().getResourceAsStream(path)) {
+			Reader reader = new InputStreamReader(in, StandardCharsets.UTF_8);
+			return new PropertyResourceBundle(reader);
+		}
+	}
+}