Don't push effects that can't be undone onto the Undo Stack

src/effects/EffectManager.cpp

@@ -42,6 +42,7 @@ EffectManager::EffectManager()
    mRealtimeSuspended = true;
    mRealtimeLatency = 0;
    mRealtimeLock.Leave();
+   mSkipStateFlag = false;
 
 #if defined(EXPERIMENTAL_EFFECTS_RACK)
    mRack = NULL;
@@ -92,6 +93,7 @@ bool EffectManager::DoEffect(const PluginID & ID,
                              bool shouldPrompt /* = true */)
 
 {
+   this->SetSkipStateFlag(false);
    Effect *effect = GetEffect(ID);
    
    if (!effect)
@@ -171,6 +173,16 @@ bool EffectManager::IsHidden(const PluginID & ID)
    return false;
 }
 
+void EffectManager::SetSkipStateFlag(bool flag)
+{
+   mSkipStateFlag = flag;
+}
+
+bool EffectManager::GetSkipStateFlag()
+{
+   return mSkipStateFlag;
+}
+
 bool EffectManager::SupportsAutomation(const PluginID & ID)
 {
    const PluginDescriptor *plug =  PluginManager::Get().GetPlugin(ID);

src/effects/EffectManager.h

@@ -91,7 +91,11 @@ public:
    wxString GetDefaultPreset(const PluginID & ID);
    void SetBatchProcessing(const PluginID & ID, bool start);
 
-      // Realtime effect processing
+   /** Allow effects to disable saving the state at run time */
+   void SetSkipStateFlag(bool flag);
+   bool GetSkipStateFlag();
+
+   // Realtime effect processing
    bool RealtimeIsActive();
    bool RealtimeIsSuspended();
    void RealtimeAddEffect(Effect *effect);
@@ -135,6 +139,10 @@ private:
    wxArrayInt mRealtimeChans;
    wxArrayDouble mRealtimeRates;
 
+   // Set true if we want to skip pushing state 
+   // after processing at effect run time.
+   bool mSkipStateFlag;
+
 #if defined(EXPERIMENTAL_EFFECTS_RACK)
    EffectRack *mRack;
 

src/effects/NoiseReduction.cpp

@@ -39,6 +39,7 @@
 #include "../Audacity.h"
 #include "../Experimental.h"
 #include "NoiseReduction.h"
+#include "EffectManager.h"
 
 #include "../ShuttleGui.h"
 #include "../Prefs.h"
@@ -1616,6 +1617,9 @@ void EffectNoiseReduction::Dialog::EnableDisableSensitivityControls()
 
 void EffectNoiseReduction::Dialog::OnGetProfile(wxCommandEvent & WXUNUSED(event))
 {
+   // Project has not be changed so skip pushing state
+   EffectManager::Get().SetSkipStateFlag(true);
+
    if (!TransferDataFromWindow())
       return;
 

src/effects/nyquist/Nyquist.cpp

@@ -437,6 +437,9 @@ bool NyquistEffect::CheckWhetherSkipEffect()
 bool NyquistEffect::Process()
 {
    bool success = true;
+   mProjectChanged = false;
+   EffectManager & em = EffectManager::Get();
+   em.SetSkipStateFlag(false);
 
    if (mExternal) {
       mProgress->Hide();
@@ -622,6 +625,8 @@ bool NyquistEffect::Process()
          if (mCurLen > NYQ_MAX_LEN) {
             wxMessageBox(_("Selection too long for Nyquist code.\nMaximum allowed selection is 2147483647 samples\n(about 13.5 hours at 44100 Hz sample rate)."),
                          _("Nyquist Error"), wxOK | wxCENTRE);
+            if (!mProjectChanged)
+               em.SetSkipStateFlag(true);
             return false;
          }
 
@@ -721,6 +726,9 @@ bool NyquistEffect::Process()
 
    mDebug = false;
 
+   if (!mProjectChanged)
+      em.SetSkipStateFlag(true);
+
    return success;
 }
 
@@ -1091,6 +1099,7 @@ bool NyquistEffect::ProcessOne()
    }
 
    if (rval == nyx_labels) {
+      mProjectChanged = true;
       unsigned int numLabels = nyx_get_num_labels();
       unsigned int l;
       LabelTrack *ltrack = NULL;
@@ -1233,7 +1242,7 @@ bool NyquistEffect::ProcessOne()
       delete mOutputTrack[i];
       mOutputTrack[i] = NULL;
    }
-
+   mProjectChanged = true;
    return true;
 }
 

src/effects/nyquist/Nyquist.h

@@ -199,6 +199,7 @@ private:
    bool              mEnablePreview;
    bool              mDebug;
    bool              mRedirectOutput;
+   bool              mProjectChanged;
    wxString          mDebugOutput;
 
    int               mVersion;