Do not use GUI language for shortcut info inset if no translation is available

Fixes: #11508

Now there is the opposite case which needs to be addressed:
If no translation is available for a shortcut in a non-latin-scripted
document, we need to switch the language to English.

src/KeyMap.cpp

@@ -476,7 +476,8 @@ docstring const KeyMap::print(bool forgui) const
 
 
 docstring KeyMap::printBindings(FuncRequest const & func,
-				KeySequence::outputFormat format) const
+				KeySequence::outputFormat format,
+				bool const untranslated) const
 {
 	Bindings bindings = findBindings(func);
 	if (bindings.empty())
@@ -486,10 +487,10 @@ docstring KeyMap::printBindings(FuncRequest const & func,
 	Bindings::const_iterator cit = bindings.begin();
 	Bindings::const_iterator cit_end = bindings.end();
 	// print the first item
-	res << cit->print(format);
+	res << cit->print(format, untranslated);
 	// more than one shortcuts?
 	for (++cit; cit != cit_end; ++cit)
-		res << ", " << cit->print(format);
+		res << ", " << cit->print(format, untranslated);
 	return res.str();
 }
 

src/KeyMap.h

@@ -118,7 +118,8 @@ public:
 
 	/// Given an action, print the keybindings.
 	docstring printBindings(FuncRequest const & func,
-				KeySequence::outputFormat format) const;
+				KeySequence::outputFormat format,
+				bool const untranslated = false) const;
 
 	struct Binding {
 		Binding(FuncRequest const & r, KeySequence const & s, ItemType t)

src/KeySequence.cpp

@@ -133,7 +133,7 @@ size_t KeySequence::parse(string const & s)
 }
 
 
-docstring const KeySequence::print(outputFormat format) const
+docstring const KeySequence::print(outputFormat format, bool const untranslated) const
 {
 	docstring buf;
 
@@ -142,10 +142,10 @@ docstring const KeySequence::print(outputFormat format) const
 	for (size_t i = 0; i != length; ++i) {
 		switch (format) {
 		case Portable:
-			buf += sequence[i].print(modifiers[i].first, false);
+			buf += sequence[i].print(modifiers[i].first, false, untranslated);
 			break;
 		case ForGui:
-			buf += sequence[i].print(modifiers[i].first, true);
+			buf += sequence[i].print(modifiers[i].first, true, untranslated);
 			break;
 		case BindFile:
 			KeyModifier mod = modifiers[i].first;

src/KeySequence.h

@@ -72,7 +72,7 @@ public:
 	 * @param format output format
 	 * @see parse()
 	 */
-	docstring const print(outputFormat format) const;
+	docstring const print(outputFormat format, bool const untranslated = false) const;
 
 	/**
 	 * Return the current sequence and available options as

src/frontends/KeySymbol.h

@@ -56,7 +56,7 @@ public:
 	 * Use the native UI format when \c forgui is true.
 	 * i.e. (translated and with special characters for Mac OS X)
 	 */
-	docstring const print(KeyModifier mod, bool forgui) const;
+	docstring const print(KeyModifier mod, bool forgui, bool untranslated = false) const;
 
 	///
 	int key() const { return key_; }

src/frontends/qt4/GuiKeySymbol.cpp

@@ -686,7 +686,7 @@ char_type KeySymbol::getUCSEncoded() const
 }
 
 
-docstring const KeySymbol::print(KeyModifier mod, bool forgui) const
+docstring const KeySymbol::print(KeyModifier mod, bool forgui, bool untranslated) const
 {
 	int tmpkey = key_;
 
@@ -703,7 +703,8 @@ docstring const KeySymbol::print(KeyModifier mod, bool forgui) const
 	QString str;
 
 	if (forgui)
-		str = seq.toString(QKeySequence::NativeText);
+		str = untranslated ? seq.toString(QKeySequence::PortableText)
+				   : seq.toString(QKeySequence::NativeText);
 	else {
 #ifdef Q_OS_MAC
 		// Qt/Mac does not use Command and friends in the

src/insets/InsetInfo.cpp

@@ -167,6 +167,12 @@ set<string> getTexFileList(string const & filename)
 	// remove duplicates
 	return list;
 }
+
+bool translateString(docstring const in, docstring & out, string const lcode)
+{
+	out = translateIfPossible(in, lcode);
+	return in != out;
+}
 } // namespace anon
 
 
@@ -710,15 +716,21 @@ void InsetInfo::setInfo(string const & name)
 
 void InsetInfo::error(docstring const & err, Language const * lang)
 {
-	setText(bformat(translateIfPossible(err, lang->code()), from_utf8(params_.name)),
-		Font(inherit_font, lang), false);
+	docstring const res = translateIfPossible(err, lang->code());
+	bool const translated = res != err;
+	// If the string is not translated, we use default lang (English)
+	Font const f = translated ? Font(inherit_font, lang) : Font(inherit_font);
+	setText(bformat(res, from_utf8(params_.name)), f, false);
 }
 
 
 void InsetInfo::info(docstring const & err, Language const * lang)
 {
-	setText(translateIfPossible(err, lang->code()),
-			Font(inherit_font, lang), false);
+	docstring const res = translateIfPossible(err, lang->code());
+	bool const translated = res != err;
+	// If the string is not translated, we use default lang (English)
+	Font const f = translated ? Font(inherit_font, lang) : Font(inherit_font);
+	setText(translateIfPossible(err, lang->code()), f, false);
 }
 
 
@@ -774,84 +786,105 @@ void InsetInfo::updateBuffer(ParIterator const & it, UpdateType utype) {
 			break;
 		}
 		docstring sequence;
-		if (params_.type == InsetInfoParams::SHORTCUT_INFO)
+		docstring seq_untranslated;
+		if (params_.type == InsetInfoParams::SHORTCUT_INFO) {
 			sequence = bindings.begin()->print(KeySequence::ForGui);
-		else
+			seq_untranslated = bindings.begin()->print(KeySequence::ForGui, true);
+		} else {
 			sequence = theTopLevelKeymap().printBindings(func, KeySequence::ForGui);
+			seq_untranslated = theTopLevelKeymap().printBindings(func, KeySequence::ForGui, true);
+		}
 		// QKeySequence returns special characters for keys on the mac
 		// Since these are not included in many fonts, we
 		// re-translate them to textual names (see #10641)
 		odocstringstream ods;
 		string const lcode = params_.lang->code();
+		docstring trans;
+		bool is_translated = sequence != seq_untranslated;
 		for (size_t n = 0; n < sequence.size(); ++n) {
 			char_type const c = sequence[n];
 			switch(c) {
 			case 0x21b5://Return
 				gui = _("Return[[Key]]");
-				ods << translateIfPossible(from_ascii("Return[[Key]]"), lcode);
+				is_translated = translateString(from_ascii("Return[[Key]]"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x21b9://Tab both directions (Win)
 				gui = _("Tab[[Key]]");
-				ods << translateIfPossible(from_ascii("Tab[[Key]]"), lcode);
+				is_translated = translateString(from_ascii("Tab[[Key]]"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x21de://Qt::Key_PageUp
 				gui = _("PgUp");
-				ods << translateIfPossible(from_ascii("PgUp"), lcode);
+				is_translated = translateString(from_ascii("PgUp"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x21df://Qt::Key_PageDown
 				gui = _("PgDown");
-				ods << translateIfPossible(from_ascii("PgDown"), lcode);
+				is_translated = translateString(from_ascii("PgDown"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x21e4://Qt::Key_Backtab
 				gui = _("Backtab");
-				ods << translateIfPossible(from_ascii("Backtab"), lcode);
+				is_translated = translateString(from_ascii("Backtab"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x21e5://Qt::Key_Tab
 				gui = _("Tab");
-				ods << translateIfPossible(from_ascii("Tab"), lcode);
+				is_translated = translateString(from_ascii("Tab"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x21e7://Shift
 				gui = _("Shift");
-				ods << translateIfPossible(from_ascii("Shift"), lcode);
+				is_translated = translateString(from_ascii("Shift"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x21ea://Qt::Key_CapsLock
 				gui = _("CapsLock");
-				ods << translateIfPossible(from_ascii("CapsLock"), lcode);
+				is_translated = translateString(from_ascii("CapsLock"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x2303://Control
 				gui = _("Control[[Key]]");
-				ods << translateIfPossible(from_ascii("Control[[Key]]"), lcode);
+				is_translated = translateString(from_ascii("Control[[Key]]"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x2318://CMD
 				gui = _("Command[[Key]]");
-				ods << translateIfPossible(from_ascii("Command[[Key]]"), lcode);
+				is_translated = translateString(from_ascii("Command[[Key]]"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x2324://Qt::Key_Enter
 				gui = _("Return[[Key]]");
-				ods << translateIfPossible(from_ascii("Return[[Key]]"), lcode);
+				is_translated = translateString(from_ascii("Return[[Key]]"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x2325://Option key
 				gui = _("Option[[Key]]");
-				ods << translateIfPossible(from_ascii("Option[[Key]]"), lcode);
+				is_translated = translateString(from_ascii("Option[[Key]]"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x2326://Qt::Key_Delete
 				gui = _("Delete[[Key]]");
-				ods << translateIfPossible(from_ascii("Delete[[Key]]"), lcode);
+				is_translated = translateString(from_ascii("Delete[[Key]]"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x232b://Qt::Key_Backspace
 				gui = _("Fn+Del");
-				ods << translateIfPossible(from_ascii("Fn+Delete"), lcode);
+				is_translated = translateString(from_ascii("Fn+Del"), trans, lcode);
+				ods << trans;
 				break;
 			case 0x238b://Qt::Key_Escape
 				gui = _("Esc");
-				ods << translateIfPossible(from_ascii("Esc"), lcode);
+				is_translated = translateString(from_ascii("Esc"), trans, lcode);
+				ods << trans;
 				break;
 			default:
 				ods.put(c);
 			}
 		}
-		setText(ods.str(), guilang);
-		params_.force_ltr = !guilang->rightToLeft() && !params_.lang->rightToLeft();
+		setText(ods.str(), is_translated ? guilang : nullptr);
+		params_.force_ltr = !is_translated || (!guilang->rightToLeft() && !params_.lang->rightToLeft());
 		break;
 	}
 	case InsetInfoParams::LYXRC_INFO: {