Bug2442 residual: Review AudacityException classes...

... Have copy constructors only (no moves); disallow all assignments

src/AudacityException.cpp

@@ -53,21 +53,6 @@ MessageBoxException::MessageBoxException( const MessageBoxException& that )
    that.moved = true;
 }
 
-MessageBoxException &MessageBoxException::operator = ( MessageBoxException &&that )
-{
-   caption = that.caption;
-   if ( this != &that ) {
-      AudacityException::operator=( std::move(that) );
-      if (!moved)
-         wxAtomicDec( sOutstandingMessages );
-
-      moved = that.moved;
-      that.moved = true;
-   }
-
-   return *this;
-}
-
 MessageBoxException::~MessageBoxException()
 {
    if (!moved)

src/AudacityException.h

@@ -33,10 +33,14 @@ public:
 
 protected:
    // Make this protected to prevent slicing copies
-   AudacityException( AudacityException&& ) {}
    AudacityException( const AudacityException& ) = default;
-   AudacityException &operator = (AudacityException &&) { return *this;}
+
-   AudacityException &operator = ( const AudacityException & ) PROHIBITED;
+   // Don't allow moves of this class or subclasses
+   // see https://bugzilla.audacityteam.org/show_bug.cgi?id=2442
+   AudacityException( AudacityException&& ) = delete;
+
+   // Disallow assignment
+   AudacityException &operator = ( const AudacityException & ) = delete;
 };
 
 /// \brief A subclass of AudacityException whose delayed handler action displays
@@ -56,7 +60,6 @@ protected:
    ~MessageBoxException() override;
 
    MessageBoxException( const MessageBoxException& );
-   MessageBoxException &operator = ( MessageBoxException && );
 
    // Format a default error message for this exception.
    virtual TranslatableString ErrorMessage() const = 0;

src/InconsistencyException.h

@@ -32,16 +32,6 @@ public:
       , file{ that.file }
       , line{ that.line }
    {}
-   InconsistencyException &operator = (InconsistencyException &&that)
-   {
-      if (this != &that) {
-         MessageBoxException::operator= (std::move(that));
-         func = that.func;
-         file = that.file;
-         line = that.line;
-      }
-      return *this;
-   }
 
    ~InconsistencyException() override;
 

src/Sequence.cpp

@@ -1835,39 +1835,38 @@ void Sequence::ConsistencyCheck
     sampleCount mNumSamples, const wxChar *whereStr,
     bool WXUNUSED(mayThrow))
 {
-   bool bError = false;
    // Construction of the exception at the appropriate line of the function
    // gives a little more discrimination
-   InconsistencyException ex;
+   Optional<InconsistencyException> ex;
 
    unsigned int numBlocks = mBlock.size();
 
    unsigned int i;
    sampleCount pos = from < numBlocks ? mBlock[from].start : mNumSamples;
    if ( from == 0 && pos != 0 )
-      ex = CONSTRUCT_INCONSISTENCY_EXCEPTION, bError = true;
+      ex.emplace( CONSTRUCT_INCONSISTENCY_EXCEPTION );
 
-   for (i = from; !bError && i < numBlocks; i++) {
+   for (i = from; !ex && i < numBlocks; i++) {
       const SeqBlock &seqBlock = mBlock[i];
       if (pos != seqBlock.start)
-         ex = CONSTRUCT_INCONSISTENCY_EXCEPTION, bError = true;
+         ex.emplace( CONSTRUCT_INCONSISTENCY_EXCEPTION );
 
       if ( seqBlock.f ) {
          const auto length = seqBlock.f->GetLength();
          if (length > maxSamples)
-            ex = CONSTRUCT_INCONSISTENCY_EXCEPTION, bError = true;
+            ex.emplace( CONSTRUCT_INCONSISTENCY_EXCEPTION );
          pos += length;
       }
       else
-         ex = CONSTRUCT_INCONSISTENCY_EXCEPTION, bError = true;
+         ex.emplace( CONSTRUCT_INCONSISTENCY_EXCEPTION );
    }
-   if ( !bError && pos != mNumSamples )
+   if ( !ex && pos != mNumSamples )
-      ex = CONSTRUCT_INCONSISTENCY_EXCEPTION, bError = true;
+      ex.emplace( CONSTRUCT_INCONSISTENCY_EXCEPTION );
 
-   if ( bError )
+   if ( ex )
    {
       wxLogError(wxT("*** Consistency check failed at %d after %s. ***"),
-                 ex.GetLine(), whereStr);
+                 ex->GetLine(), whereStr);
       wxString str;
       DebugPrintf(mBlock, mNumSamples, &str);
       wxLogError(wxT("%s"), str);
@@ -1876,7 +1875,7 @@ void Sequence::ConsistencyCheck
                  wxT("Undo the failed operation(s), then export or save your work and quit."));
 
       //if (mayThrow)
-         //throw ex;
+         //throw *ex;
       //else
          wxASSERT(false);
    }

src/UserException.h

@@ -21,12 +21,6 @@ class UserException final : public AudacityException
 public:
    UserException() {}
 
-   UserException(UserException &&that)
-      : AudacityException{ std::move( that ) }
-   {}
-
-   UserException& operator= (UserException&&) PROHIBITED;
-
    ~UserException() override;
 
    void DelayedHandlerAction() override;

src/blockfile/NotYetAvailableException.h

@@ -18,9 +18,6 @@ class NotYetAvailableException final : public FileException
 public:
    NotYetAvailableException( const wxFileName &fileName )
       : FileException{ Cause::Read, fileName } {}
-   NotYetAvailableException(NotYetAvailableException &&that)
-      : FileException( std::move( that ) ) {}
-   NotYetAvailableException& operator= (NotYetAvailableException&&) PROHIBITED;
    ~NotYetAvailableException();
 
 protected: