Use default language strings in the XML Processor if a translation is missing (#45)

Author: prof18

lyricist-processor-xml/src/main/java/cafe/adriel/lyricist/processor/xml/internal/LyricistXmlSymbolProcessor.kt

@@ -57,8 +57,17 @@ internal class LyricistXmlSymbolProcessor(
             ?.let { writeStringsClassFile(fileName, stringsName, it, strings.keys) }
             ?: logger.error("Default language tag not found")
 
+        val defaultStrings = strings[config.defaultLanguageTag].orEmpty()
+
         strings.forEach { (languageTag, strings) ->
-            writeStringsPropertyFile(fileName, languageTag, strings)
+            val stringsWithMissingTranslations = if (languageTag != config.defaultLanguageTag) {
+                val notTranslatedStrings = defaultStrings.filterKeys { key -> !strings.containsKey(key) }
+                strings + notTranslatedStrings
+            } else {
+                strings
+            }
+
+            writeStringsPropertyFile(fileName, languageTag, stringsWithMissingTranslations)
         }
     }
 

sample-xml/src/main/res/values/strings.xml

@@ -2,6 +2,7 @@
     <string name="simple">Hello "world"</string>
     <string name="params">Parameters: %1$s, %2$d, %s, %d</string>
     <string name="replacement">@string/simple</string>
+    <string name="missing_translation">Missing translation</string>
 
     <string-array name="array">
         <item>Avocado</item>