source/blender/blenkernel/BKE_nla.h

@@ -36,10 +36,10 @@ struct PropertyRNA;
 /* Data Management */
 
 /**
- * Remove the given NLA strip from the NLA track it occupies, free the strip's data,
+ * Frees the given NLA strip, and calls #BKE_nlastrip_remove_and_free to
- * and the strip itself.
+ * remove and free all children strips.
  */
-void BKE_nlastrip_free(ListBase *strips, struct NlaStrip *strip, bool do_id_user);
+void BKE_nlastrip_free(struct NlaStrip *strip, bool do_id_user);
 /**
  * Remove the given NLA track from the set of NLA tracks, free the track's data,
  * and the track itself.
@@ -94,10 +94,22 @@ void BKE_nla_tracks_copy_from_adt(struct Main *bmain,
 struct NlaTrack *BKE_nlatrack_add(struct AnimData *adt,
                                   struct NlaTrack *prev,
                                   bool is_liboverride);
+
 /**
  * Create a NLA Strip referencing the given Action.
  */
 struct NlaStrip *BKE_nlastrip_new(struct bAction *act);
+
+/*
+ * Removes the given NLA strip from the list of strips provided.
+ */
+void BKE_nlastrip_remove(ListBase *strips, struct NlaStrip *strip);
+
+/*
+ * Removes the given NLA strip from the list of strips provided, and frees it's memory.
+ */
+void BKE_nlastrip_remove_and_free(ListBase *strips, struct NlaStrip *strip, const bool do_id_user);
+
 /**
  * Add new NLA-strip to the top of the NLA stack - i.e.
  * into the last track if space, or a new one otherwise.
@@ -139,13 +151,9 @@ void BKE_nlastrips_sort_strips(ListBase *strips);
 void BKE_nlastrips_add_strip_unsafe(ListBase *strips, struct NlaStrip *strip);
 
 /**
- * \brief NULL checks incoming strip and verifies no overlap / invalid
+ *  NULL checks incoming strip and verifies no overlap / invalid
- * configuration against other strips in NLA Track.
+ *  configuration against other strips in NLA Track before calling
- *
+ *  #BKE_nlastrips_add_strip_unsafe.
- * \param strips:
- * \param strip:
- * \return true
- * \return false
  */
 bool BKE_nlastrips_add_strip(ListBase *strips, struct NlaStrip *strip);
 
@@ -215,11 +223,16 @@ bool BKE_nlatrack_has_space(struct NlaTrack *nlt, float start, float end);
 void BKE_nlatrack_sort_strips(struct NlaTrack *nlt);
 
 /**
- * Add the given NLA-Strip to the given NLA-Track, assuming that it
+ * Add the given NLA-Strip to the given NLA-Track.
- * isn't currently attached to another one.
+ * Calls #BKE_nlastrips_add_strip to check if strip can be added.
  */
 bool BKE_nlatrack_add_strip(struct NlaTrack *nlt, struct NlaStrip *strip, bool is_liboverride);
 
+/**
+ * Remove the NLA-Strip from the given NLA-Track.
+ */
+void BKE_nlatrack_remove_strip(struct NlaTrack *track, struct NlaStrip *strip);
+
 /**
  * Get the extents of the given NLA-Track including gaps between strips,
  * returning whether this succeeded or not

source/blender/blenkernel/intern/nla.c

@@ -61,7 +61,7 @@ static void nla_tweakmode_find_active(const ListBase /* NlaTrack */ *nla_tracks,
 
 /* Freeing ------------------------------------------- */
 
-void BKE_nlastrip_free(ListBase *strips, NlaStrip *strip, bool do_id_user)
+void BKE_nlastrip_free(NlaStrip *strip, const bool do_id_user)
 {
   NlaStrip *cs, *csn;
 
@@ -73,7 +73,7 @@ void BKE_nlastrip_free(ListBase *strips, NlaStrip *strip, bool do_id_user)
   /* free child-strips */
   for (cs = strip->strips.first; cs; cs = csn) {
     csn = cs->next;
-    BKE_nlastrip_free(&strip->strips, cs, do_id_user);
+    BKE_nlastrip_remove_and_free(&strip->strips, cs, do_id_user);
   }
 
   /* remove reference to action */
@@ -81,10 +81,6 @@ void BKE_nlastrip_free(ListBase *strips, NlaStrip *strip, bool do_id_user)
     id_us_min(&strip->act->id);
   }
 
-  /* free remapping info */
-  // if (strip->remap)
-  //  BKE_animremap_free();
-
   /* free own F-Curves */
   BKE_fcurves_free(&strip->fcurves);
 
@@ -92,12 +88,7 @@ void BKE_nlastrip_free(ListBase *strips, NlaStrip *strip, bool do_id_user)
   free_fmodifiers(&strip->modifiers);
 
   /* free the strip itself */
-  if (strips) {
-    BLI_freelinkN(strips, strip);
-  }
-  else {
   MEM_freeN(strip);
-  }
 }
 
 void BKE_nlatrack_free(ListBase *tracks, NlaTrack *nlt, bool do_id_user)
@@ -112,7 +103,7 @@ void BKE_nlatrack_free(ListBase *tracks, NlaTrack *nlt, bool do_id_user)
   /* free strips */
   for (strip = nlt->strips.first; strip; strip = stripn) {
     stripn = strip->next;
-    BKE_nlastrip_free(&nlt->strips, strip, do_id_user);
+    BKE_nlastrip_remove_and_free(&nlt->strips, strip, do_id_user);
   }
 
   /* free NLA track itself now */
@@ -875,7 +866,7 @@ void BKE_nlastrips_clear_metastrip(ListBase *strips, NlaStrip *strip)
   }
 
   /* free the meta-strip now */
-  BKE_nlastrip_free(strips, strip, true);
+  BKE_nlastrip_remove_and_free(strips, strip, true);
 }
 
 void BKE_nlastrips_clear_metas(ListBase *strips, bool only_sel, bool only_temp)
@@ -1190,6 +1181,12 @@ bool BKE_nlatrack_add_strip(NlaTrack *nlt, NlaStrip *strip, const bool is_libove
   return BKE_nlastrips_add_strip(&nlt->strips, strip);
 }
 
+void BKE_nlatrack_remove_strip(NlaTrack *track, NlaStrip *strip)
+{
+  BLI_assert(track);
+  BKE_nlastrip_remove(&track->strips, strip);
+}
+
 bool BKE_nlatrack_get_bounds(NlaTrack *nlt, float bounds[2])
 {
   NlaStrip *strip;
@@ -1318,6 +1315,18 @@ NlaStrip *BKE_nlastrip_find_active(NlaTrack *nlt)
   return nlastrip_find_active(&nlt->strips);
 }
 
+void BKE_nlastrip_remove(ListBase *strips, NlaStrip *strip)
+{
+  BLI_assert(strips);
+  BLI_remlink(strips, strip);
+}
+
+void BKE_nlastrip_remove_and_free(ListBase *strips, NlaStrip *strip, const bool do_id_user)
+{
+  BKE_nlastrip_remove(strips, strip);
+  BKE_nlastrip_free(strip, do_id_user);
+}
+
 void BKE_nlastrip_set_active(AnimData *adt, NlaStrip *strip)
 {
   NlaTrack *nlt;

source/blender/blenkernel/intern/nla_test.cc

@@ -1,6 +1,8 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later
  * Copyright 2023 Blender Foundation. All rights reserved. */
 
+#include "BLI_listbase.h"
+
 #include "BKE_nla.h"
 
 #include "DNA_anim_types.h"
@@ -20,19 +22,19 @@ TEST(nla_strip, BKE_nlastrip_recalculate_blend)
   strip.start = 1;
   strip.end = 10;
 
-  /* Scaling a strip up doesn't affect the blend in/out value */
+  /* Scaling a strip up doesn't affect the blend in/out value. */
   strip.end = 20;
   BKE_nlastrip_recalculate_blend(&strip);
   EXPECT_FLOAT_EQ(strip.blendin, 4.0);
   EXPECT_FLOAT_EQ(strip.blendout, 5.0);
 
-  /* Scaling a strip down affects the blend-in value before the blend-out value  */
+  /* Scaling a strip down affects the blend-in value before the blend-out value.  */
   strip.end = 7;
   BKE_nlastrip_recalculate_blend(&strip);
   EXPECT_FLOAT_EQ(strip.blendin, 1.0);
   EXPECT_FLOAT_EQ(strip.blendout, 5.0);
 
-  /* Scaling a strip down to nothing updates the blend in/out values accordingly  */
+  /* Scaling a strip down to nothing updates the blend in/out values accordingly.  */
   strip.end = 1.1;
   BKE_nlastrip_recalculate_blend(&strip);
   EXPECT_FLOAT_EQ(strip.blendin, 0.0);
@@ -63,4 +65,31 @@ TEST(nla_strip, BKE_nlastrips_add_strip)
   EXPECT_TRUE(BKE_nlastrips_add_strip(&strips, &strip2));
 }
 
+TEST(nla_track, BKE_nlatrack_remove_strip)
+{
+  NlaTrack track{};
+  ListBase strips{};
+  NlaStrip strip1{};
+  strip1.start = 0;
+  strip1.end = 10;
+
+  NlaStrip strip2{};
+  strip2.start = 11;
+  strip2.end = 20;
+
+  // Add NLA strips to the NLATrack.
+  BKE_nlastrips_add_strip(&strips, &strip1);
+  BKE_nlastrips_add_strip(&strips, &strip2);
+  track.strips = strips;
+
+  // ensure we have 2 strips in the track.
+  EXPECT_EQ(2, BLI_listbase_count(&track.strips));
+
+  BKE_nlatrack_remove_strip(&track, &strip2);
+  EXPECT_EQ(1, BLI_listbase_count(&track.strips));
+  // ensure the correct strip was removed.
+  EXPECT_EQ(-1, BLI_findindex(&track.strips, &strip2));
+}
+
 }  // namespace blender::bke::tests
+

source/blender/editors/space_action/action_data.c

@@ -586,7 +586,7 @@ void ED_animedit_unlink_action(
 
             if (strip->act == act) {
               /* Remove this strip, and the track too if it doesn't have anything else */
-              BKE_nlastrip_free(&nlt->strips, strip, true);
+              BKE_nlastrip_remove_and_free(&nlt->strips, strip, true);
 
               if (nlt->strips.first == NULL) {
                 BLI_assert(nstrip == NULL);

source/blender/editors/space_nla/nla_edit.c

@@ -1305,15 +1305,15 @@ static int nlaedit_delete_exec(bContext *C, wmOperator *UNUSED(op))
       if (strip->flag & NLASTRIP_FLAG_SELECT) {
         /* if a strip either side of this was a transition, delete those too */
         if ((strip->prev) && (strip->prev->type == NLASTRIP_TYPE_TRANSITION)) {
-          BKE_nlastrip_free(&nlt->strips, strip->prev, true);
+          BKE_nlastrip_remove_and_free(&nlt->strips, strip->prev, true);
         }
         if ((nstrip) && (nstrip->type == NLASTRIP_TYPE_TRANSITION)) {
           nstrip = nstrip->next;
-          BKE_nlastrip_free(&nlt->strips, strip->next, true);
+          BKE_nlastrip_remove_and_free(&nlt->strips, strip->next, true);
         }
 
         /* finally, delete this strip */
-        BKE_nlastrip_free(&nlt->strips, strip, true);
+        BKE_nlastrip_remove_and_free(&nlt->strips, strip, true);
       }
     }
   }
@@ -1824,7 +1824,7 @@ static int nlaedit_move_up_exec(bContext *C, wmOperator *UNUSED(op))
         if (BKE_nlatrack_has_space(nltn, strip->start, strip->end)) {
           /* remove from its current track, and add to the one above
            * (it 'should' work, so no need to worry) */
-          BLI_remlink(&nlt->strips, strip);
+          BKE_nlatrack_remove_strip(nlt, strip);
           BKE_nlatrack_add_strip(nltn, strip, is_liboverride);
         }
       }
@@ -1916,7 +1916,7 @@ static int nlaedit_move_down_exec(bContext *C, wmOperator *UNUSED(op))
         if (BKE_nlatrack_has_space(nltp, strip->start, strip->end)) {
           /* remove from its current track, and add to the one above
            * (it 'should' work, so no need to worry) */
-          BLI_remlink(&nlt->strips, strip);
+          BKE_nlatrack_remove_strip(nlt, strip);
           BKE_nlatrack_add_strip(nltp, strip, is_liboverride);
         }
       }

source/blender/editors/transform/transform_convert_nla.c

@@ -457,7 +457,7 @@ static void recalcData_nla(TransInfo *t)
           if (BKE_nlatrack_has_space(track, strip->start, strip->end) &&
               !BKE_nlatrack_is_nonlocal_in_liboverride(tdn->id, track)) {
             /* move strip to this track */
-            BLI_remlink(&tdn->nlt->strips, strip);
+            BKE_nlatrack_remove_strip(tdn->nlt, strip);
             BKE_nlatrack_add_strip(track, strip, is_liboverride);
 
             tdn->nlt = track;
@@ -477,7 +477,7 @@ static void recalcData_nla(TransInfo *t)
           if (BKE_nlatrack_has_space(track, strip->start, strip->end) &&
               !BKE_nlatrack_is_nonlocal_in_liboverride(tdn->id, track)) {
             /* move strip to this track */
-            BLI_remlink(&tdn->nlt->strips, strip);
+            BKE_nlatrack_remove_strip(tdn->nlt, strip);
             BKE_nlatrack_add_strip(track, strip, is_liboverride);
 
             tdn->nlt = track;

source/blender/makesrna/intern/rna_nla.c

@@ -544,7 +544,7 @@ static NlaStrip *rna_NlaStrip_new(ID *id,
         reports,
         RPT_ERROR,
         "Unable to add strip (the track does not have any space to accommodate this new strip)");
-    BKE_nlastrip_free(NULL, strip, true);
+    BKE_nlastrip_free(strip, true);
     return NULL;
   }
 
@@ -595,7 +595,7 @@ static void rna_NlaStrip_remove(
     return;
   }
 
-  BKE_nlastrip_free(&track->strips, strip, true);
+  BKE_nlastrip_remove_and_free(&track->strips, strip, true);
   RNA_POINTER_INVALIDATE(strip_ptr);
 
   WM_event_add_notifier(C, NC_ANIMATION | ND_NLA | NA_REMOVED, NULL);