fix: Exact plural forms for basic MT translators

backend/data/src/main/kotlin/io/tolgee/service/machineTranslation/PluralTranslationUtil.kt

@@ -12,21 +12,14 @@ class PluralTranslationUtil(
  private val item: MtBatchItemParams,
  private val translateFn: (String) -> MtTranslatorResult,
 ) {
- val forms by lazy {
- context.getPluralFormsReplacingReplaceParam(baseTranslationText)
- ?: throw IllegalStateException("Plural forms are null")
- }
-
  fun translate(): MtTranslatorResult {
  return result
  }
 
  private val preparedFormSourceStrings: Sequence<Pair<String, String>> by lazy {
- return@lazy targetExamples.asSequence().map {
- val form = sourceRules?.select(it.value.toDouble())
- val formValue = forms.forms[form] ?: forms.forms[PluralRules.KEYWORD_OTHER] ?: ""
- it.key to formValue.replaceReplaceNumberPlaceholderWithExample(it.value)
- }
+ val targetLanguageTag = context.getLanguage(item.targetLanguageId).tag
+ val sourceLanguageTag = context.baseLanguage.tag
+ getPreparedSourceStrings(sourceLanguageTag, targetLanguageTag, forms)
  }
 
  private val translated by lazy {
@@ -35,6 +28,11 @@ class PluralTranslationUtil(
  }
  }
 
+ private val forms by lazy {
+ context.getPluralFormsReplacingReplaceParam(baseTranslationText)
+ ?: throw IllegalStateException("Plural forms are null")
+ }
+
  private val result: MtTranslatorResult by lazy {
  val result =
  translated.map { (form, result) ->
@@ -59,18 +57,6 @@ class PluralTranslationUtil(
  )
  }
 
- private val targetExamples by lazy {
- val targetLanguageTag = context.getLanguage(item.targetLanguageId).tag
- val targetULocale = getULocaleFromTag(targetLanguageTag)
- val targetRules = PluralRules.forLocale(targetULocale)
- getPluralFormExamples(targetRules)
- }
-
- private val sourceRules by lazy {
- val sourceLanguageTag = context.baseLanguage.tag
- getRulesByTag(sourceLanguageTag)
- }
-
  private fun String.replaceNumberTags(): String {
  return this.replace(TOLGEE_TAG_REGEX, "#")
  }
@@ -126,5 +112,43 @@ class PluralTranslationUtil(
  val sourceULocale = getULocaleFromTag(languageTag)
  return PluralRules.forLocale(sourceULocale)
  }
+
+ fun getPreparedSourceStrings(
+ sourceLanguageTag: String,
+ targetLanguageTag: String,
+ forms: PluralForms,
+ ): Sequence<Pair<String, String>> {
+ val sourceRules = getRulesByTag(sourceLanguageTag)
+ val keywordCases =
+ getTargetExamples(targetLanguageTag).asSequence().map {
+ val form = sourceRules?.select(it.value.toDouble())
+ val formValue = forms.forms[form] ?: forms.forms[PluralRules.KEYWORD_OTHER] ?: ""
+ it.key to formValue.replaceReplaceNumberPlaceholderWithExample(it.value)
+ }
+
+ val exactCases =
+ forms.forms.asSequence().filter {
+ it.key.startsWith("=")
+ }.mapNotNull {
+ val number = it.key.substring(1).toDoubleOrNull() ?: return@mapNotNull null
+ it.key to it.value.replaceReplaceNumberPlaceholderWithExample(number)
+ }
+
+ return keywordCases + exactCases
+ }
+
+ private fun String.toDoubleOrNull(): Number? {
+ return try {
+ this.toBigDecimalOrNull()
+ } catch (e: NumberFormatException) {
+ null
+ }
+ }
+
+ private fun getTargetExamples(targetLanguageTag: String): Map<String, Number> {
+ val targetULocale = getULocaleFromTag(targetLanguageTag)
+ val targetRules = PluralRules.forLocale(targetULocale)
+ return getPluralFormExamples(targetRules)
+ }
  }
 }

backend/data/src/test/kotlin/io/tolgee/unit/util/PluralTranslationUtilTest.kt

@@ -0,0 +1,31 @@
+package io.tolgee.unit.util
+
+import io.tolgee.formats.getPluralFormsReplacingReplaceParam
+import io.tolgee.service.machineTranslation.PluralTranslationUtil
+import io.tolgee.testing.assert
+import org.junit.jupiter.api.Test
+
+class PluralTranslationUtilTest {
+ @Test
+ fun `provides correct forms for basic MT providers`() {
+ val baseString = """{number, plural, one {# apple} =1 {one apple} =2 {Two apples} =5 {# apples} other {# apples}}"""
+ val result =
+ PluralTranslationUtil.getPreparedSourceStrings(
+ "en",
+ "cs",
+ getPluralFormsReplacingReplaceParam(baseString, PluralTranslationUtil.REPLACE_NUMBER_PLACEHOLDER)!!,
+ )
+
+ result.toMap().assert.isEqualTo(
+ mapOf(
+ "one" to "<x id=\"tolgee-number\">1</x> apple",
+ "few" to "<x id=\"tolgee-number\">2</x> apples",
+ "many" to "<x id=\"tolgee-number\">0.5</x> apples",
+ "other" to "<x id=\"tolgee-number\">10</x> apples",
+ "=1" to "one apple",
+ "=2" to "Two apples",
+ "=5" to "<x id=\"tolgee-number\">5</x> apples",
+ ),
+ )
+ }
+}