Merge pull request #68 from sillsdev/avoid-substitution-if-no-transla…

…tion

In LanguageChoosingDialog, handle off-line case where translator just returns source string

CHANGELOG.md

@@ -16,6 +16,9 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
+### Fixed
+
+- If translator returns an unmodified source string, don't substitute the English language name for the vernacular name.
 
 ## [4.0.1] - 2019-07-08
 

src/L10NSharp/UI/LanguageChoosingDialog.cs

@@ -20,7 +20,7 @@ public LanguageChoosingDialog(L10NCultureInfo requestedCulture, Icon icon)
 		void Application_Idle(object sender, EventArgs e)
 		{
 			Application.Idle -= Application_Idle;
-			_model.SetTranslator(new BingTranslator("en", _model.RequestedCultureTwoLetterISOLanguageName));
+			_model.TranslateStrings(new BingTranslator("en", _model.RequestedCultureTwoLetterISOLanguageName));
 			_messageLabel.Text = _model.Message;
 			_OKButton.Text = _model.AcceptButtonText;
 			Text = _model.WindowTitle;

src/L10NSharp/UI/LanguageChoosingDialogViewModel.cs

@@ -1,16 +1,30 @@
 using System;
+using System.Diagnostics;
 using L10NSharp.Translators;
 
 namespace L10NSharp.UI
 {
-	public class LanguageChoosingDialogViewModel
+	internal class LanguageChoosingDialogViewModel
 	{
 		private readonly L10NCultureInfo _requestedCulture;
 		private readonly string _messageLabelFormat;
 		private readonly string _acceptButtonText;
 		private readonly string _windowTitle;
 
-		public LanguageChoosingDialogViewModel(string messageLabelFormat, string acceptButtonText, string windowTitle,
+		/// <summary>
+		/// Creates a new LanguageChoosingDialogViewModel object to handle (asynchronous) translation of message and other UI strings
+		/// displayed in the LanguageChoosingDialog.
+		/// </summary>
+		/// <param name="messageLabelFormat">Format string where param {0} is the native name of the requested UI language/culture and
+		/// param {1} is the English name of the requested UI language/culture</param>
+		/// <param name="acceptButtonText">The "OK" button text (not a format string)</param>
+		/// <param name="windowTitle">The dialog's title (not a format string)</param>
+		/// <param name="requestedCulture">The requested UI language/culture. Typically, this will not be English (though in some of
+		/// the tests it is)</param>
+		/// <param name="nonEnglishUiAction">An action that should be performed only if the requested culture is not English. In
+		/// production, this action will set up an action to be performed (once) on idle so that TranslateStrings can be called and
+		/// the UI can be updated to reflect the newly translated strings, if appropriate.</param>
+		internal LanguageChoosingDialogViewModel(string messageLabelFormat, string acceptButtonText, string windowTitle,
 			L10NCultureInfo requestedCulture, Action nonEnglishUiAction)
 		{
 			_messageLabelFormat = messageLabelFormat;
@@ -27,11 +41,14 @@ public LanguageChoosingDialogViewModel(string messageLabelFormat, string acceptB
 				nonEnglishUiAction?.Invoke();
 		}
 
-		public void SetTranslator(TranslatorBase translator)
+		internal void TranslateStrings(TranslatorBase translator)
 		{
 			try
 			{
-				var s = translator.TranslateText(string.Format(_messageLabelFormat, _requestedCulture.EnglishName, "{0}"));
+				var sourceString = string.Format(_messageLabelFormat, _requestedCulture.EnglishName, "{0}");
+				var s = translator.TranslateText(sourceString);
+				if (s == sourceString)
+					return;
 				if (s.Contains("{0}") && s.Length > 5) // If we just get back "{0} or "({0})", we won't consider that useful.
 				{
 					// Bing will presumably have translated the English string into the native language, so now we want
@@ -62,9 +79,9 @@ public void SetTranslator(TranslatorBase translator)
 			}
 		}
 
-		public string RequestedCultureTwoLetterISOLanguageName => _requestedCulture.TwoLetterISOLanguageName;
-		public string Message { get; private set; }
-		public string AcceptButtonText { get; private set; }
-		public string WindowTitle { get; private set; }
+		internal string RequestedCultureTwoLetterISOLanguageName => _requestedCulture.TwoLetterISOLanguageName;
+		internal string Message { get; private set; }
+		internal string AcceptButtonText { get; private set; }
+		internal string WindowTitle { get; private set; }
 	}
 }

src/L10NSharpTests/LanguageChoosingDialogViewModelTests.cs

@@ -85,58 +85,58 @@ public void Constructor_BogusFormatString_Throws(string format)
 		}
 
 		[Test]
-		public void SetTranslator_RequestedCultureEnglish_TranslationAppliedOnceToEachString()
+		public void TranslateStrings_RequestedCultureEnglish_TranslationAppliedOnceToEachString()
 		{
 			var model = new LanguageChoosingDialogViewModel("Blah {0} ({1}) yup!", "OK", "Choose a Language",
 				L10NCultureInfo.GetCultures(CultureTypes.NeutralCultures).First(c => c.TwoLetterISOLanguageName == "en"),
 				null);
 			Assert.AreEqual("Blah English yup!", model.Message);
 			var translator = new TestTranslatorBumpyFrog();
-			model.SetTranslator(translator);
+			model.TranslateStrings(translator);
 			Assert.AreEqual("Bumpy frog Blah English yup!", model.Message);
 			Assert.AreEqual("Bumpy frog OK", model.AcceptButtonText);
 			Assert.AreEqual("Bumpy frog Choose a Language", model.WindowTitle);
 			Assert.IsTrue(translator.SourceStrings.SequenceEqual(new[] { "Blah English yup!", "OK", "Choose a Language" }));
 		}
 
 		[Test]
-		public void SetTranslator_RequestedCultureGermanNormalTranslation_TranslationAppliedOnceToEachString()
+		public void TranslateStrings_RequestedCultureGermanNormalTranslation_TranslationAppliedOnceToEachString()
 		{
 			var model = new LanguageChoosingDialogViewModel("No localization for {0} ({1})", "OK", "Choose a Language",
 				L10NCultureInfo.GetCultures(CultureTypes.NeutralCultures).First(c => c.TwoLetterISOLanguageName == "de"),
 				null);
 			Assert.AreEqual("No localization for German (Deutsch)", model.Message);
 			var translator = new TestTranslatorGerman();
-			model.SetTranslator(translator);
+			model.TranslateStrings(translator);
 			Assert.AreEqual("Ich spreche No localization for Deutsch (German)", model.Message);
 			Assert.AreEqual("Ich spreche OK", model.AcceptButtonText);
 			Assert.AreEqual("Ich spreche Choose a Language", model.WindowTitle);
 			Assert.IsTrue(translator.SourceStrings.SequenceEqual(new[] { "No localization for German ({0})", "OK", "Choose a Language" }));
 		}
 
 		[Test]
-		public void SetTranslator_ChangeTranslator_TranslationAppliedToOriginalString()
+		public void TranslateStrings_ChangeTranslator_TranslationAppliedToOriginalString()
 		{
 			var model = new LanguageChoosingDialogViewModel("No localization for {0} ({1})", "OK", "Choose a Language",
 				L10NCultureInfo.GetCultures(CultureTypes.NeutralCultures).First(c => c.TwoLetterISOLanguageName == "de"),
 				null);
 			Assert.AreEqual("No localization for German (Deutsch)", model.Message);
-			model.SetTranslator(new TestTranslatorBumpyFrog());
-			model.SetTranslator(new TestTranslatorGerman());
+			model.TranslateStrings(new TestTranslatorBumpyFrog());
+			model.TranslateStrings(new TestTranslatorGerman());
 			Assert.AreEqual("Ich spreche No localization for Deutsch (German)", model.Message);
 			Assert.AreEqual("Ich spreche OK", model.AcceptButtonText);
 			Assert.AreEqual("Ich spreche Choose a Language", model.WindowTitle);
 		}
 
 		[Test]
-		public void SetTranslator_RequestedCultureSpanishChokesOnFormatParam_TranslationReappliedToStringWithoutParam()
+		public void TranslateStrings_RequestedCultureSpanishChokesOnFormatParam_TranslationReappliedToStringWithoutParam()
 		{
 			var model = new LanguageChoosingDialogViewModel("No localization for {0} ({1})", "OK", "Choose a Language",
 				L10NCultureInfo.GetCultures(CultureTypes.NeutralCultures).First(c => c.TwoLetterISOLanguageName == "es"),
 				null);
 			Assert.AreEqual("No localization for Spanish (español)", model.Message);
 			var translator = new TestTranslatorSpanishChokesOnFormatParam();
-			model.SetTranslator(translator);
+			model.TranslateStrings(translator);
 			// Note: the test translator mimics Bing's behavior of replacing the English name of the requested language with the word "English" in the translation.
 			Assert.AreEqual("No choke No localization for English (español)", model.Message);
 			Assert.AreEqual("No choke OK", model.AcceptButtonText);
@@ -145,13 +145,27 @@ public void SetTranslator_RequestedCultureSpanishChokesOnFormatParam_Translation
 		}
 
 		[Test]
-		public void SetTranslator_TranslatorThrowsException_ExceptionSwallowedAndNoAttemptToTranslateOtherStrings()
+		public void TranslateStrings_TranslatorThrowsException_ExceptionSwallowedAndNoAttemptToTranslateOtherStrings()
 		{
 			var model = new LanguageChoosingDialogViewModel("No localization for {0} ({1})", "Okey-dokey", "Select a Language",
 				L10NCultureInfo.GetCultures(CultureTypes.NeutralCultures).First(c => c.TwoLetterISOLanguageName == "es"),
 				null);
 			var translator = new TestTranslatorThrowsException();
-			model.SetTranslator(translator);
+			model.TranslateStrings(translator);
+			Assert.AreEqual("No localization for Spanish (español)", model.Message);
+			Assert.AreEqual("Okey-dokey", model.AcceptButtonText);
+			Assert.AreEqual("Select a Language", model.WindowTitle);
+			Assert.IsTrue(translator.SourceStrings.SequenceEqual(new[] { "No localization for Spanish ({0})" }));
+		}
+
+		[Test]
+		public void TranslateStrings_TranslatorReturnsSourceString_NoAttemptToSubstituteEnglishNameOrTranslateOtherStrings()
+		{
+			var model = new LanguageChoosingDialogViewModel("No localization for {0} ({1})", "Okey-dokey", "Select a Language",
+				L10NCultureInfo.GetCultures(CultureTypes.NeutralCultures).First(c => c.TwoLetterISOLanguageName == "es"),
+				null);
+			var translator = new TestTranslatorBase(); // This translator just returns unmodified source string
+			model.TranslateStrings(translator);
 			Assert.AreEqual("No localization for Spanish (español)", model.Message);
 			Assert.AreEqual("Okey-dokey", model.AcceptButtonText);
 			Assert.AreEqual("Select a Language", model.WindowTitle);