One less delegating ctor of SnapManager, move code to TimeShiftHandle

src/Snap.cpp

@@ -69,65 +69,6 @@ SnapPointArray FindCandidates( const TrackList &tracks )
    }
    return candidates;
 }
-
-SnapPointArray FindCandidates(
-   const TrackList &tracks,
-   const TrackClipArray *clipExclusions, const TrackArray *trackExclusions )
-{
-   // Special case restricted candidates for time shift
-   SnapPointArray candidates;
-   auto trackRange =
-      tracks.Any()
-         - [&](const Track *pTrack){
-            return trackExclusions &&
-               make_iterator_range( *trackExclusions ).contains( pTrack );
-         };
-   trackRange.Visit(
-      [&](const LabelTrack *labelTrack) {
-         for (int i = 0, cnt = labelTrack->GetNumLabels(); i < cnt; ++i)
-         {
-            const LabelStruct *label = labelTrack->GetLabel(i);
-            const double t0 = label->getT0();
-            const double t1 = label->getT1();
-            candidates.emplace_back(t0, labelTrack);
-            if (t1 != t0)
-               candidates.emplace_back(t1, labelTrack);
-         }
-      },
-      [&](const WaveTrack *waveTrack) {
-         for (const auto &clip: waveTrack->GetClips())
-         {
-            if (clipExclusions)
-            {
-               bool skip = false;
-               for (size_t j = 0, cnt = clipExclusions->size(); j < cnt; ++j)
-               {
-                  if ((*clipExclusions)[j].track == waveTrack &&
-                      (*clipExclusions)[j].clip == clip.get())
-                  {
-                     skip = true;
-                     break;
-                  }
-               }
-
-               if (skip)
-                  continue;
-            }
-
-            candidates.emplace_back(clip->GetStartTime(), waveTrack);
-            candidates.emplace_back(clip->GetEndTime(), waveTrack);
-         }
-      }
-#ifdef USE_MIDI
-      ,
-      [&](const NoteTrack *track) {
-         candidates.emplace_back(track->GetStartTime(), track);
-         candidates.emplace_back(track->GetEndTime(), track);
-      }
-#endif
-   );
-   return candidates;
-}
 }
 
 SnapManager::SnapManager(const AudacityProject &project,
@@ -141,19 +82,6 @@ SnapManager::SnapManager(const AudacityProject &project,
 {
 }
 
-SnapManager::SnapManager(const AudacityProject &project,
-                         const TrackList &tracks,
-                         const ZoomInfo &zoomInfo,
-                         bool noTimeSnap,
-                         int pixelTolerance,
-                         const TrackClipArray *clipExclusions,
-                         const TrackArray *trackExclusions)
-   : SnapManager{ project,
-      FindCandidates( tracks, clipExclusions, trackExclusions ),
-      zoomInfo, noTimeSnap, pixelTolerance }
-{
-}
-
 SnapManager::~SnapManager()
 {
 }

src/Snap.h

@@ -89,13 +89,6 @@ public:
                bool noTimeSnap = false,
                int pixelTolerance = kPixelTolerance);
 
-   SnapManager(const AudacityProject &project,
-               const TrackList &tracks,
-               const ZoomInfo &zoomInfo,
-               bool noTimeSnap,
-               int pixelTolerance,
-               const TrackClipArray *clipExclusions = NULL,
-               const TrackArray *trackExclusions = NULL);
    ~SnapManager();
 
    // The track may be NULL.

src/tracks/ui/TimeShiftHandle.cpp

@@ -350,6 +350,64 @@ void TimeShiftHandle::DoSlideHorizontal
       DoOffset( state, &capturedTrack, state.hSlideAmount );
 }
 
+#include "LabelTrack.h"
+namespace {
+SnapPointArray FindCandidates(
+   const TrackList &tracks,
+   const TrackClipArray &clipExclusions, const TrackArray &trackExclusions )
+{
+   // Special case restricted candidates for time shift
+   SnapPointArray candidates;
+   auto trackRange =
+      tracks.Any()
+         - [&](const Track *pTrack){
+            return
+               make_iterator_range( trackExclusions ).contains( pTrack );
+         };
+   trackRange.Visit(
+      [&](const LabelTrack *labelTrack) {
+         for (const auto &label : labelTrack->GetLabels())
+         {
+            const double t0 = label.getT0();
+            const double t1 = label.getT1();
+            candidates.emplace_back(t0, labelTrack);
+            if (t1 != t0)
+               candidates.emplace_back(t1, labelTrack);
+         }
+      },
+      [&](const WaveTrack *waveTrack) {
+         for (const auto &clip: waveTrack->GetClips())
+         {
+            bool skip = false;
+            for (const auto &exclusion : clipExclusions)
+            {
+               if (exclusion.track == waveTrack &&
+                   exclusion.clip == clip.get())
+               {
+                  skip = true;
+                  break;
+               }
+            }
+
+            if (skip)
+               continue;
+
+            candidates.emplace_back(clip->GetStartTime(), waveTrack);
+            candidates.emplace_back(clip->GetEndTime(), waveTrack);
+         }
+      }
+#ifdef USE_MIDI
+      ,
+      [&](const NoteTrack *track) {
+         candidates.emplace_back(track->GetStartTime(), track);
+         candidates.emplace_back(track->GetEndTime(), track);
+      }
+#endif
+   );
+   return candidates;
+}
+}
+
 UIHandle::Result TimeShiftHandle::Click
 (const TrackPanelMouseEvent &evt, AudacityProject *pProject)
 {
@@ -415,12 +473,12 @@ UIHandle::Result TimeShiftHandle::Click
    mRect = rect;
    mClipMoveState.mMouseClickX = event.m_x;
    mSnapManager =
-   std::make_shared<SnapManager>(*trackList.GetOwner(), trackList,
+   std::make_shared<SnapManager>(*trackList.GetOwner(),
-          viewInfo,
+       FindCandidates( trackList,
-          true, // don't snap to time
+         mClipMoveState.capturedClipArray, mClipMoveState.trackExclusions),
-          kPixelTolerance,
+       viewInfo,
-          &mClipMoveState.capturedClipArray,
+       true, // don't snap to time
-          &mClipMoveState.trackExclusions);
+       kPixelTolerance);
    mClipMoveState.snapLeft = -1;
    mClipMoveState.snapRight = -1;
    mSnapPreferRightEdge =