ModuleInterface::GetFileExtensions() returns const reference...

... avoiding repeated array allocation

include/audacity/ModuleInterface.h

@@ -84,7 +84,7 @@ public:
    // This function returns nonempty only when that is the case, and lists
    // the possible extensions of such files (an empty string in a nonempty
    // array means any file is a candidate).
-   virtual FileExtensions GetFileExtensions() = 0;
+   virtual const FileExtensions &GetFileExtensions() = 0;
 
    // Returns empty, or else, where to copy a plug-in file or bundle.
    // Drag-and-drop is supported only if GetFileExtensions() returns nonempty and

src/PluginManager.cpp

@@ -1787,7 +1787,7 @@ bool PluginManager::DropFile(const wxString &fileName)
          continue;
 
       const auto &ff = module->InstallPath();
-      auto extensions = module->GetFileExtensions();
+      const auto &extensions = module->GetFileExtensions();
       if ( !ff.empty() &&
           extensions.Index(src.GetExt(), false) != wxNOT_FOUND ) {
          wxString errMsg;

src/commands/LoadCommands.cpp

@@ -228,6 +228,12 @@ void BuiltinCommandsModule::Terminate()
    return;
 }
 
+const FileExtensions &BuiltinCommandsModule::GetFileExtensions()
+{
+   static FileExtensions empty;
+   return empty;
+}
+
 bool BuiltinCommandsModule::AutoRegisterPlugins(PluginManagerInterface & pm)
 {
    wxString ignoredErrMsg;

src/commands/LoadCommands.h

@@ -40,7 +40,7 @@ public:
    bool Initialize() override;
    void Terminate() override;
 
-   FileExtensions GetFileExtensions() override { return {}; }
+   const FileExtensions &GetFileExtensions() override;
    FilePath InstallPath() override { return {}; }
 
    bool AutoRegisterPlugins(PluginManagerInterface & pm) override;

src/effects/LoadEffects.cpp

@@ -293,6 +293,12 @@ void BuiltinEffectsModule::Terminate()
    return;
 }
 
+const FileExtensions &BuiltinEffectsModule::GetFileExtensions()
+{
+   static FileExtensions empty;
+   return empty;
+}
+
 bool BuiltinEffectsModule::AutoRegisterPlugins(PluginManagerInterface & pm)
 {
    wxString ignoredErrMsg;

src/effects/LoadEffects.h

@@ -39,7 +39,7 @@ public:
    bool Initialize() override;
    void Terminate() override;
 
-   FileExtensions GetFileExtensions() override { return {}; }
+   const FileExtensions &GetFileExtensions() override;
    FilePath InstallPath() override { return {}; }
 
    bool AutoRegisterPlugins(PluginManagerInterface & pm) override;

src/effects/VST/VSTEffect.cpp

@@ -370,9 +370,10 @@ void VSTEffectsModule::Terminate()
    return;
 }
 
-FileExtensions VSTEffectsModule::GetFileExtensions()
+const FileExtensions &VSTEffectsModule::GetFileExtensions()
 {
-   return {{ _T("vst") }};
+   static FileExtensions result{{ _T("vst") }};
+   return result;
 }
 
 FilePath VSTEffectsModule::InstallPath()

src/effects/VST/VSTEffect.h

@@ -416,7 +416,7 @@ public:
    bool Initialize() override;
    void Terminate() override;
 
-   FileExtensions GetFileExtensions() override;
+   const FileExtensions &GetFileExtensions() override;
    FilePath InstallPath() override;
 
    bool AutoRegisterPlugins(PluginManagerInterface & pm) override;

src/effects/audiounits/AudioUnitEffect.cpp

@@ -137,9 +137,10 @@ wxString AudioUnitEffectsModule::GetDescription()
 // ModuleInterface implementation
 // ============================================================================
 
-FileExtensions AudioUnitEffectsModule::GetFileExtensions()
+const FileExtensions &AudioUnitEffectsModule::GetFileExtensions()
 {
-   return {{ _T("au") }};
+   static FileExtensions result{{ _T("au") }};
+   return result;
 }
 
 bool AudioUnitEffectsModule::Initialize()

src/effects/audiounits/AudioUnitEffect.h

@@ -241,7 +241,7 @@ public:
    bool Initialize() override;
    void Terminate() override;
 
-   FileExtensions GetFileExtensions() override;
+   const FileExtensions &GetFileExtensions() override;
    FilePath InstallPath() override { return {}; }
 
    bool AutoRegisterPlugins(PluginManagerInterface & pm) override;

src/effects/ladspa/LadspaEffect.cpp

@@ -156,9 +156,9 @@ void LadspaEffectsModule::Terminate()
    return;
 }
 
-FileExtensions LadspaEffectsModule::GetFileExtensions()
+const FileExtensions &LadspaEffectsModule::GetFileExtensions()
 {
-   return {{
+   static FileExtensions result{{
 
 #ifdef __WXMSW__
 
@@ -176,6 +176,7 @@ FileExtensions LadspaEffectsModule::GetFileExtensions()
 #endif
 
    }};
+   return result;
 }
 
 FilePath LadspaEffectsModule::InstallPath()

src/effects/ladspa/LadspaEffect.h

@@ -222,7 +222,7 @@ public:
    bool Initialize() override;
    void Terminate() override;
 
-   FileExtensions GetFileExtensions() override;
+   const FileExtensions &GetFileExtensions() override;
    FilePath InstallPath() override;
 
    bool AutoRegisterPlugins(PluginManagerInterface & pm) override;

src/effects/lv2/LoadLV2.cpp

@@ -207,6 +207,12 @@ void LV2EffectsModule::Terminate()
    return;
 }
 
+const FileExtensions &LV2EffectsModule::GetFileExtensions()
+{
+   static FileExtensions empty;
+   return empty;
+}
+
 bool LV2EffectsModule::AutoRegisterPlugins(PluginManagerInterface & WXUNUSED(pm))
 {
    return false;

src/effects/lv2/LoadLV2.h

@@ -86,7 +86,7 @@ public:
    bool Initialize() override;
    void Terminate() override;
 
-   FileExtensions GetFileExtensions() override { return {}; }
+   const FileExtensions &GetFileExtensions() override;
    FilePath InstallPath() override { return {}; }
 
    bool AutoRegisterPlugins(PluginManagerInterface & pm) override;

src/effects/nyquist/LoadNyquist.cpp

@@ -156,9 +156,10 @@ void NyquistEffectsModule::Terminate()
    return;
 }
 
-FileExtensions NyquistEffectsModule::GetFileExtensions()
+const FileExtensions &NyquistEffectsModule::GetFileExtensions()
 {
-   return {{ _T("ny") }};
+   static FileExtensions result{{ _T("ny") }};
+   return result;
 }
 
 FilePath NyquistEffectsModule::InstallPath()

src/effects/nyquist/LoadNyquist.h

@@ -37,7 +37,7 @@ public:
    bool Initialize() override;
    void Terminate() override;
 
-   FileExtensions GetFileExtensions() override;
+   const FileExtensions &GetFileExtensions() override;
    FilePath InstallPath() override;
 
    bool AutoRegisterPlugins(PluginManagerInterface & pm) override;

src/effects/vamp/LoadVamp.cpp

@@ -112,9 +112,10 @@ void VampEffectsModule::Terminate()
    return;
 }
 
-FileExtensions VampEffectsModule::GetFileExtensions()
+const FileExtensions &VampEffectsModule::GetFileExtensions()
 {
-   return {};
+   static FileExtensions empty;
+   return empty;
 }
 
 bool VampEffectsModule::AutoRegisterPlugins(PluginManagerInterface & WXUNUSED(pm))

src/effects/vamp/LoadVamp.h

@@ -45,7 +45,7 @@ public:
    bool Initialize() override;
    void Terminate() override;
 
-   FileExtensions GetFileExtensions() override;
+   const FileExtensions &GetFileExtensions() override;
    FilePath InstallPath() override { return {}; }
 
    bool AutoRegisterPlugins(PluginManagerInterface & pm) override;