A few bugfixes:

* #19583: Keying Sets list issues
Deleting a Keying Set (or a Keying Set Path) set the active index to 0, but that would mean that the first item would be selected but not visible.

* #19590: Keyframing properties of a modifier with more than one of it's type the property will highlight in all
- Modifiers now always have a unique name, so renaming a modifier should check that the name is unique. Most of the files changed in this commit were just to make sure that modifiers got unique names when they were created
- Modifiers path getter was wrapped a bit wrong (missing the "s around the name)

* Constraints Bugs
- Constraints renaming now also makes sure the names stay unique
- Fixed (or attempted to fix) compiler warnings about some enum declaration for distance constraint

source/blender/blenkernel/BKE_modifier.h

@@ -274,6 +274,8 @@ ModifierTypeInfo *modifierType_getInfo (ModifierType type);
 struct ModifierData  *modifier_new(int type);
 void          modifier_free(struct ModifierData *md);
 
+void 		  modifier_unique_name(struct ListBase *modifiers, struct ModifierData *md);
+
 void          modifier_copyData(struct ModifierData *md, struct ModifierData *target);
 int           modifier_dependsOnTime(struct ModifierData *md);
 int           modifier_supportsMapping(struct ModifierData *md);

source/blender/blenkernel/intern/modifier.c

@@ -34,6 +34,7 @@
 *
 */
 
+#include "stddef.h"
 #include "string.h"
 #include "stdarg.h"
 #include "math.h"
@@ -8761,7 +8762,8 @@ ModifierData *modifier_new(int type)
 {
 	ModifierTypeInfo *mti = modifierType_getInfo(type);
 	ModifierData *md = MEM_callocN(mti->structSize, mti->structName);
-
+	
+	// FIXME: we need to make the name always be unique somehow...
 	strcpy(md->name, mti->name);
 
 	md->type = type;
@@ -8786,6 +8788,15 @@ void modifier_free(ModifierData *md)
 	MEM_freeN(md);
 }
 
+void modifier_unique_name(ListBase *modifiers, ModifierData *md)
+{
+	if (modifiers && md) {
+		ModifierTypeInfo *mti = modifierType_getInfo(md->type);
+		
+		BLI_uniquename(modifiers, md, mti->name, '.', offsetof(ModifierData, name), sizeof(md->name));
+	}
+}
+
 int modifier_dependsOnTime(ModifierData *md) 
 {
 	ModifierTypeInfo *mti = modifierType_getInfo(md->type);

source/blender/blenkernel/intern/multires.c

@@ -142,6 +142,7 @@ void multiresModifier_join(Object *ob)
 				
 				mmd = (MultiresModifierData*)modifier_new(eModifierType_Multires);
 				BLI_insertlinkbefore(&base->object->modifiers, md, mmd);
+				modifier_unique_name(&base->object->modifiers, mmd);
 			}
 
 			if(mmd)

source/blender/blenloader/intern/readfile.c

@@ -4095,6 +4095,8 @@ static void direct_link_object(FileData *fd, Object *ob)
 
 		BLI_addhead(&ob->modifiers, hmd);
 		BLI_remlink(&ob->hooks, hook);
+		
+		modifier_unique_name(&ob->modifiers, hmd);
 
 		MEM_freeN(hook);
 	}
@@ -7659,6 +7661,8 @@ static void do_versions(FileData *fd, Library *lib, Main *main)
 						smd->flags |= eSubsurfModifierFlag_ControlEdges;
 					
 					BLI_addtail(&ob->modifiers, smd);
+					
+					modifier_unique_name(&ob->modifiers, smd);
 				}
 			}
 			

source/blender/editors/animation/keyingsets.c

@@ -177,9 +177,10 @@ static int remove_active_keyingset_exec (bContext *C, wmOperator *op)
 	
 	/* free KeyingSet's data, then remove it from the scene */
 	BKE_keyingset_free(ks);
-	
 	BLI_freelinkN(&scene->keyingsets, ks);
-	scene->active_keyingset= 0;
+	
+	/* the active one should now be the previously second-to-last one */
+	scene->active_keyingset--;
 	
 	return OPERATOR_FINISHED;
 }
@@ -258,8 +259,8 @@ static int remove_active_ks_path_exec (bContext *C, wmOperator *op)
 				BLI_freelinkN(&ks->paths, ksp);
 			}
 			
-			/* fix active path index */
+			/* the active path should now be the previously second-to-last active one */
-			ks->active_path= 0;
+			ks->active_path--;
 		}
 		else {
 			BKE_report(op->reports, RPT_ERROR, "No active Keying Set Path to remove");

source/blender/editors/interface/interface_templates.c

@@ -458,6 +458,8 @@ static void modifiers_convertToReal(bContext *C, void *ob_v, void *md_v)
 	nmd->mode &= ~eModifierMode_Virtual;
 
 	BLI_addhead(&ob->modifiers, nmd);
+	
+	modifier_unique_name(&ob->modifiers, nmd);
 
 	ob->partype = PAROBJECT;
 

source/blender/editors/object/object_edit.c

@@ -848,6 +848,7 @@ void special_editmenu(Scene *scene, View3D *v3d)
 								BooleanModifierData *bmd = NULL;
 								bmd = (BooleanModifierData *)modifier_new(eModifierType_Boolean);
 								BLI_addtail(&ob->modifiers, bmd);
+								modifier_unique_name(&ob->modifiers, bmd);
 								bmd->object = base_select->object;
 								bmd->modifier.mode |= eModifierMode_Realtime;
 								switch(nr){
@@ -978,9 +979,10 @@ static void object_flip_subdivison_particles(Scene *scene, Object *ob, int *set,
 			} 
 			else if(depth == 0 && *set != 0) {
 				SubsurfModifierData *smd = (SubsurfModifierData*) modifier_new(eModifierType_Subsurf);
-
+				
 				BLI_addtail(&ob->modifiers, smd);
-
+				modifier_unique_name(&ob->modifiers, smd);
+				
 				if (level!=-1) {
 					smd->levels = level;
 				}
@@ -1197,6 +1199,7 @@ static void copymenu_modifiers(Scene *scene, View3D *v3d, Object *ob)
 							nmd = modifier_new(md->type);
 							modifier_copyData(md, nmd);
 							BLI_addtail(&base->object->modifiers, nmd);
+							modifier_unique_name(&base->object->modifiers, nmd);
 						}
 
 						copy_object_particlesystems(base->object, ob);
@@ -1220,6 +1223,7 @@ static void copymenu_modifiers(Scene *scene, View3D *v3d, Object *ob)
 								
 								mdn = modifier_new(event);
 								BLI_addtail(&base->object->modifiers, mdn);
+								modifier_unique_name(&base->object->modifiers, mdn);
 
 								modifier_copyData(md, mdn);
 							}

source/blender/editors/object/object_hook.c

@@ -480,6 +480,7 @@ void add_hook(Scene *scene, View3D *v3d, int mode)
 				hmd = (HookModifierData*) modifier_new(eModifierType_Hook);
 				BLI_insertlinkbefore(&obedit->modifiers, md, hmd);
 				sprintf(hmd->modifier.name, "Hook-%s", ob->id.name+2);
+				modifier_unique_name(&obedit->modifiers, hmd);
 			}
 			else if (hmd->indexar) MEM_freeN(hmd->indexar); /* reassign, hook was set */
 		

source/blender/editors/object/object_modifier.c

@@ -76,7 +76,7 @@
 
 int ED_object_modifier_add(ReportList *reports, Scene *scene, Object *ob, int type)
 {
-	ModifierData *md;
+	ModifierData *md=NULL, *new_md=NULL;
 	ModifierTypeInfo *mti = modifierType_getInfo(type);
 
 	if(mti->flags&eModifierTypeFlag_Single) {
@@ -87,19 +87,28 @@ int ED_object_modifier_add(ReportList *reports, Scene *scene, Object *ob, int ty
 	}
 
 	if(type == eModifierType_ParticleSystem) {
+		/* don't need to worry about the new modifier's name, since that is set to the number
+		 * of particle systems which shouldn't have too many duplicates 
+		 */
 		object_add_particle_system(scene, ob);
 	}
 	else {
+		/* get new modifier data to add */
+		new_md= modifier_new(type);
+		
 		if(mti->flags&eModifierTypeFlag_RequiresOriginalData) {
 			md = ob->modifiers.first;
-
+			
 			while(md && modifierType_getInfo(md->type)->type==eModifierTypeType_OnlyDeform)
 				md = md->next;
-
+			
-			BLI_insertlinkbefore(&ob->modifiers, md, modifier_new(type));
+			BLI_insertlinkbefore(&ob->modifiers, md, new_md);
 		}
 		else
-			BLI_addtail(&ob->modifiers, modifier_new(type));
+			BLI_addtail(&ob->modifiers, new_md);
+		
+		/* make sure modifier data has unique name */
+		modifier_unique_name(&ob->modifiers, new_md);
 		
 		/* special cases */
 		if(type == eModifierType_Softbody) {
@@ -111,7 +120,7 @@ int ED_object_modifier_add(ReportList *reports, Scene *scene, Object *ob, int ty
 		else if(type == eModifierType_Collision) {
 			if(!ob->pd)
 				ob->pd= object_add_collision_fields(0);
-
+			
 			ob->pd->deflect= 1;
 			DAG_scene_sort(scene);
 		}
@@ -400,6 +409,7 @@ int ED_object_modifier_copy(ReportList *reports, Object *ob, ModifierData *md)
 	nmd = modifier_new(md->type);
 	modifier_copyData(md, nmd);
 	BLI_insertlink(&ob->modifiers, md, nmd);
+	modifier_unique_name(&ob->modifiers, nmd);
 
 	return 1;
 }

source/blender/makesrna/intern/rna_constraint.c

@@ -87,13 +87,6 @@ EnumPropertyItem constraint_ik_type_items[] ={
 	{0, NULL, 0, NULL, NULL},
 };
 
-EnumPropertyItem constraint_distance_items[] = {
-	{LIMITDIST_INSIDE, "LIMITDIST_INSIDE", 0, "Inside", ""},
-	{LIMITDIST_OUTSIDE, "LIMITDIST_OUTSIDE", 0, "Outside", ""},
-	{LIMITDIST_ONSURFACE, "LIMITDIST_ONSURFACE", 0, "On Surface", ""},
-	{0, NULL, 0, NULL, NULL}
-};
-
 #ifdef RNA_RUNTIME
 
 #include "BKE_action.h"
@@ -153,6 +146,24 @@ static StructRNA *rna_ConstraintType_refine(struct PointerRNA *ptr)
 	}
 }
 
+static void rna_Constraint_name_set(PointerRNA *ptr, const char *value)
+{
+	bConstraint *con= ptr->data;
+	
+	/* copy the new name into the name slot */
+	BLI_strncpy(con->name, value, sizeof(con->name));
+	
+	/* make sure name is unique */
+	if (ptr->id.data) {
+		Object *ob= ptr->id.data;
+		ListBase *list= get_active_constraints(ob);
+		
+		/* if we have the list, check for unique name, otherwise give up */
+		if (list)
+			unique_constraint_name(con, list); 
+	}
+}
+
 static char *rna_Constraint_path(PointerRNA *ptr)
 {
 	Object *ob= ptr->id.data;
@@ -291,6 +302,14 @@ static void rna_ActionConstraint_minmax_range(PointerRNA *ptr, float *min, float
 
 #else
 
+EnumPropertyItem constraint_distance_items[] = {
+	{LIMITDIST_INSIDE, "LIMITDIST_INSIDE", 0, "Inside", ""},
+	{LIMITDIST_OUTSIDE, "LIMITDIST_OUTSIDE", 0, "Outside", ""},
+	{LIMITDIST_ONSURFACE, "LIMITDIST_ONSURFACE", 0, "On Surface", ""},
+	{0, NULL, 0, NULL, NULL}
+};
+
+
 static void rna_def_constrainttarget(BlenderRNA *brna)
 {
 	StructRNA *srna;
@@ -1606,6 +1625,7 @@ void RNA_def_constraint(BlenderRNA *brna)
 	
 	/* strings */
 	prop= RNA_def_property(srna, "name", PROP_STRING, PROP_NONE);
+	RNA_def_property_string_funcs(prop, NULL, NULL, "rna_Constraint_name_set");
 	RNA_def_property_ui_text(prop, "Name", "");
 	RNA_def_struct_name_property(srna, prop);
 	

source/blender/makesrna/intern/rna_fluidsim.c

@@ -114,6 +114,7 @@ static void rna_FluidSettings_update_type(bContext *C, PointerRNA *ptr)
 			sprintf(psmd->modifier.name, "FluidParticleSystem" );
 			psmd->psys= psys;
 			BLI_addtail(&ob->modifiers, psmd);
+			modifier_unique_name(&ob->modifiers, psmd);
 		}
 	}
 	else {

source/blender/makesrna/intern/rna_modifier.c

@@ -85,6 +85,7 @@ EnumPropertyItem modifier_type_items[] ={
 #include "BKE_context.h"
 #include "BKE_depsgraph.h"
 #include "BKE_library.h"
+#include "BKE_modifier.h"
 
 static void rna_UVProject_projectors_begin(CollectionPropertyIterator *iter, PointerRNA *ptr)
 {
@@ -164,9 +165,23 @@ static StructRNA* rna_Modifier_refine(struct PointerRNA *ptr)
 	}
 }
 
+void rna_Modifier_name_set(PointerRNA *ptr, const char *value)
+{
+	ModifierData *md= ptr->data;
+	
+	/* copy the new name into the name slot */
+	BLI_strncpy(md->name, value, sizeof(md->name));
+	
+	/* make sure the name is truly unique */
+	if (ptr->id.data) {
+		Object *ob= ptr->id.data;
+		modifier_unique_name(&ob->modifiers, md);
+	}
+}
+
 static char *rna_Modifier_path(PointerRNA *ptr)
 {
-	return BLI_sprintfN("modifiers[%s]", ((ModifierData*)ptr->data)->name);  // XXX not unique
+	return BLI_sprintfN("modifiers[\"%s\"]", ((ModifierData*)ptr->data)->name);
 }
 
 static void rna_Modifier_update(bContext *C, PointerRNA *ptr)
@@ -1911,6 +1926,7 @@ void RNA_def_modifier(BlenderRNA *brna)
 	
 	/* strings */
 	prop= RNA_def_property(srna, "name", PROP_STRING, PROP_NONE);
+	RNA_def_property_string_funcs(prop, NULL, NULL, "rna_Modifier_name_set");
 	RNA_def_property_ui_text(prop, "Name", "Modifier name.");
 	RNA_def_struct_name_property(srna, prop);