Show an error message when switching to a language that isn't installed

Also, ensure that the language names are not translated in the menus
and messages, since they are already translated in the code.

Fixes https://gitlab.com/kicad/code/kicad/issues/5324

common/eda_base_frame.cpp

@@ -36,6 +36,7 @@
 #include <settings/app_settings.h>
 #include <settings/common_settings.h>
 #include <settings/settings_manager.h>
+#include <pgm_base.h>
 #include <project/project_local_settings.h>
 #include <tool/action_manager.h>
 #include <tool/action_menu.h>
@@ -343,9 +344,6 @@ void EDA_BASE_FRAME::HandleUpdateUIEvent( wxUpdateUIEvent& aEvent, EDA_BASE_FRAM
 }
 
 
-// Contained inside pgm_base.cpp
-extern LANGUAGE_DESCR LanguagesList[];
-
 void EDA_BASE_FRAME::setupUIConditions()
 {
     // Setup the conditions to check a language menu item

common/kiway.cpp

@@ -2,7 +2,7 @@
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
  * Copyright (C) 2014 SoftPLC Corporation, Dick Hollenbeck <dick@softplc.com>
- * Copyright (C) 2014-2017 KiCad Developers, see CHANGELOG.TXT for contributors.
+ * Copyright (C) 2014-2020 KiCad Developers, see CHANGELOG.TXT for contributors.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -32,6 +32,7 @@
 #include <config.h>
 #include <id.h>
 #include <settings/settings_manager.h>
+#include <logging.h>
 
 #include <wx/stdpaths.h>
 #include <wx/debug.h>
@@ -439,8 +440,39 @@ void KIWAY::ExpressMail( FRAME_T aDestination, MAIL_T aCommand, std::string& aPa
 
 void KIWAY::SetLanguage( int aLanguage )
 {
-    Pgm().SetLanguageIdentifier( aLanguage );
-    Pgm().SetLanguage();
+    wxString errMsg;
+    bool     ret = false;
+
+    {
+        // Only allow the traces to be logged by wx. We use our own system to log when the
+        // OS doesn't support the language, so we want to hide the wx error.
+        WX_LOG_TRACE_ONLY logtraceOnly;
+        Pgm().SetLanguageIdentifier( aLanguage );
+        ret = Pgm().SetLanguage( errMsg );
+    }
+
+    if( !ret )
+    {
+        wxString lang;
+
+        for( unsigned ii = 0;  LanguagesList[ii].m_KI_Lang_Identifier != 0; ii++ )
+        {
+            if( aLanguage == LanguagesList[ii].m_KI_Lang_Identifier )
+            {
+                if( LanguagesList[ii].m_DoNotTranslate )
+                    lang = LanguagesList[ii].m_Lang_Label;
+                else
+                    lang = wxGetTranslation( LanguagesList[ii].m_Lang_Label );
+
+                break;
+            }
+        }
+
+        DisplayErrorMessage( nullptr,
+                             wxString::Format( _( "Unable to switch language to %s" ), lang ),
+                             errMsg );
+        return;
+    }
 
 #if 1
     // This is a risky hack that goes away if we allow the language to be

common/languages_menu.cpp

@@ -36,9 +36,7 @@
 #include <tool/action_menu.h>
 #include <tool/conditional_menu.h>
 #include <bitmaps.h>
-
-// Contained inside pgm_base.cpp
-extern LANGUAGE_DESCR LanguagesList[];
+#include <pgm_base.h>
 
 /**
  * Function AddMenuLanguageList

common/pgm_base.cpp

@@ -72,23 +72,23 @@ LANGUAGE_DESCR LanguagesList[] =
 {
     { wxLANGUAGE_DEFAULT,    ID_LANGUAGE_DEFAULT,    _( "Default" ),    false },
     { wxLANGUAGE_ENGLISH,    ID_LANGUAGE_ENGLISH,    wxT( "English" ),  true },
-    { wxLANGUAGE_FRENCH,     ID_LANGUAGE_FRENCH,     wxT( "Français" ), false },
-    { wxLANGUAGE_SPANISH,    ID_LANGUAGE_SPANISH,    wxT( "Español" ),  false },
-    { wxLANGUAGE_PORTUGUESE, ID_LANGUAGE_PORTUGUESE, wxT( "Português" ),false },
-    { wxLANGUAGE_ITALIAN,    ID_LANGUAGE_ITALIAN,    wxT( "Italiano" ), false },
-    { wxLANGUAGE_GERMAN,     ID_LANGUAGE_GERMAN,     wxT( "Deutsch" ),  false },
-    { wxLANGUAGE_GREEK,      ID_LANGUAGE_GREEK,      wxT( "Ελληνικά" ), false },
-    { wxLANGUAGE_HUNGARIAN,  ID_LANGUAGE_HUNGARIAN,  wxT( "Magyar" ),   false },
-    { wxLANGUAGE_POLISH,     ID_LANGUAGE_POLISH,     wxT( "Polski" ),   false },
-    { wxLANGUAGE_CZECH,      ID_LANGUAGE_CZECH,      wxT( "Čeština" ),  false },
-    { wxLANGUAGE_RUSSIAN,    ID_LANGUAGE_RUSSIAN,    wxT( "Русский" ),  false },
+    { wxLANGUAGE_FRENCH,     ID_LANGUAGE_FRENCH,     wxT( "Français" ), true },
+    { wxLANGUAGE_SPANISH,    ID_LANGUAGE_SPANISH,    wxT( "Español" ),  true },
+    { wxLANGUAGE_PORTUGUESE, ID_LANGUAGE_PORTUGUESE, wxT( "Português" ),true },
+    { wxLANGUAGE_ITALIAN,    ID_LANGUAGE_ITALIAN,    wxT( "Italiano" ), true },
+    { wxLANGUAGE_GERMAN,     ID_LANGUAGE_GERMAN,     wxT( "Deutsch" ),  true },
+    { wxLANGUAGE_GREEK,      ID_LANGUAGE_GREEK,      wxT( "Ελληνικά" ), true },
+    { wxLANGUAGE_HUNGARIAN,  ID_LANGUAGE_HUNGARIAN,  wxT( "Magyar" ),   true },
+    { wxLANGUAGE_POLISH,     ID_LANGUAGE_POLISH,     wxT( "Polski" ),   true },
+    { wxLANGUAGE_CZECH,      ID_LANGUAGE_CZECH,      wxT( "Čeština" ),  true },
+    { wxLANGUAGE_RUSSIAN,    ID_LANGUAGE_RUSSIAN,    wxT( "Русский" ),  true },
     { wxLANGUAGE_CHINESE_SIMPLIFIED, ID_LANGUAGE_CHINESE_SIMPLIFIED,
-            wxT( "简体中文" ), false },
+            wxT( "简体中文" ), true },
     { wxLANGUAGE_CHINESE_TRADITIONAL, ID_LANGUAGE_CHINESE_TRADITIONAL,
             wxT( "繁體中文" ), false },
-    { wxLANGUAGE_CATALAN,    ID_LANGUAGE_CATALAN,    wxT( "Català" ),   false },
-    { wxLANGUAGE_JAPANESE,   ID_LANGUAGE_JAPANESE,   wxT( "日本語" ),    false },
-    { wxLANGUAGE_LITHUANIAN, ID_LANGUAGE_LITHUANIAN, wxT( "Lietuvių" ), false },
+    { wxLANGUAGE_CATALAN,    ID_LANGUAGE_CATALAN,    wxT( "Català" ),   true },
+    { wxLANGUAGE_JAPANESE,   ID_LANGUAGE_JAPANESE,   wxT( "日本語" ),    true },
+    { wxLANGUAGE_LITHUANIAN, ID_LANGUAGE_LITHUANIAN, wxT( "Lietuvių" ), true },
     { 0, 0, "", false }         // Sentinel
 };
 #undef _
@@ -434,7 +434,8 @@ bool PGM_BASE::InitPgm()
     // Init user language *before* calling loadCommonSettings, because
     // env vars could be incorrectly initialized on Linux
     // (if the value contains some non ASCII7 chars, the env var is not initialized)
-    SetLanguage( true );
+    wxString tmp;
+    SetLanguage( tmp, true );
 
     loadCommonSettings();
 
@@ -559,10 +560,8 @@ COMMON_SETTINGS* PGM_BASE::GetCommonSettings() const
 }
 
 
-bool PGM_BASE::SetLanguage( bool first_time )
+bool PGM_BASE::SetLanguage( wxString& aErrMsg, bool first_time )
 {
-    bool     retv = true;
-
     if( first_time )
     {
         setLanguageId( wxLANGUAGE_DEFAULT );
@@ -596,7 +595,9 @@ bool PGM_BASE::SetLanguage( bool first_time )
 
         m_locale = new wxLocale;
         m_locale->Init();
-        retv = false;
+
+        aErrMsg = _( "This language is not supported by the operating system." );
+        return false;
     }
     else if( !first_time )
     {
@@ -636,18 +637,32 @@ bool PGM_BASE::SetLanguage( bool first_time )
     double result;
     msg.ToDouble( &result );
 
+    // string to double encode/decode does not work! Bug detected:
+    // Disable floating point localization:
     if( result != dtst )
-        // string to double encode/decode does not work! Bug detected:
-        // Disable floating point localization:
         setlocale( LC_NUMERIC, "C" );
 
+    // Try adding the dictionary if it is not currently loaded
     if( !m_locale->IsLoaded( dictionaryName ) )
         m_locale->AddCatalog( dictionaryName );
 
-    if( !retv )
-        return retv;
+    // Verify the dictionary was loaded properly
+    if( !m_locale->IsLoaded( dictionaryName ) )
+    {
+        wxLogTrace( traceLocale, "Unable to load dictionary %s.mo in %s",
+                    GetChars( dictionaryName ), GetChars( m_locale->GetName() ) );
+
+        setLanguageId( wxLANGUAGE_DEFAULT );
+        delete m_locale;
+
+        m_locale = new wxLocale;
+        m_locale->Init();
+
+        aErrMsg = _( "The KiCad language file for this language is not installed." );
+        return false;
+    }
 
-    return m_locale->IsOk();
+    return true;
 }
 
 

include/logging.h

@@ -0,0 +1,45 @@
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2020 Ian McInerney <ian.s.mcinerney at ieee dot org>
+ * Copyright (C) 2020 KiCad Developers, see AUTHORS.TXT for contributors.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you may find one here:
+ * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+ * or you may search the http://www.gnu.org website for the version 2 license,
+ * or you may write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+#include <wx/log.h>
+
+/**
+ * A logger class that filters out all log messages that are not generated by wxLogTrace
+ * and ignores them, while passing the trace messages onwards.
+ */
+class WX_LOG_TRACE_ONLY : public wxLogInterposerTemp
+{
+public:
+    WX_LOG_TRACE_ONLY() : wxLogInterposerTemp()
+    {
+    }
+
+protected:
+    void DoLogRecord( wxLogLevel aLevel, const wxString& aMsg, const wxLogRecordInfo& aInfo ) override
+    {
+        // Only forward the message if it is a trace message
+        if( aLevel == wxLOG_Trace )
+            wxLogInterposerTemp::DoLogRecord( aLevel, aMsg, aInfo );
+    }
+};

include/pgm_base.h

@@ -52,7 +52,7 @@ class SETTINGS_MANAGER;
  *   The locale translation is automatic.
  *   The selection of languages is mainly for maintainer's convenience
  *   To add a support to a new translation:
- *   add a new item to s_Languages[].
+ *   add a new item to LanguagesList[].
  */
 struct LANGUAGE_DESCR
 {
@@ -69,6 +69,10 @@ struct LANGUAGE_DESCR
     bool        m_DoNotTranslate;
 };
 
+/**
+ * An array containing all the languages that KiCad supports.
+ */
+extern LANGUAGE_DESCR LanguagesList[];
 
 // inter program module calling
 #define VTBL_ENTRY      virtual
@@ -224,16 +228,16 @@ public:
     VTBL_ENTRY void ForceSystemPdfBrowser( bool aFlg ) { m_use_system_pdf_browser = aFlg; }
 
     /**
-     * Function SetLanguage
      * sets the dictionary file name for internationalization.
      * <p>
      * The files are in kicad/internat/xx or kicad/internat/xx_XX and are named kicad.mo
      * </p>
-     * @param   first_time  must be set to true the first time this funct is
-     *          called, false otherwise
-     * @return  true if the language can be set (i.e. if the locale is available)
+     * @param aErrMsg is the string to return the error message it
+     * @param first_time  must be set to true the first time this function is
+     *        called, false otherwise
+     * @return false if there was an error setting the language
      */
-    VTBL_ENTRY bool SetLanguage( bool first_time = false );
+    VTBL_ENTRY bool SetLanguage( wxString& aErrMsg, bool first_time = false );
 
     /**
      * Function SetLanguageIdentifier