fix(sync): sync feature layer changes

This commits adds a way to differenciate "end of edit" events that are
triggered rightfully and the one which are triggered during the deletion
of a feature.

Also, directly call the `sync.upsert()` method after the move happened.

umap/static/umap/js/umap.features.js

@@ -15,7 +15,18 @@ U.FeatureMixin = {
   onCommit: function () {
     // When the layer is a remote layer, we don't want to sync the creation of the
     // points via the websocket, as the other peers will get them themselves.
-    if (this.datalayer.isRemoteLayer()) return
+    if (this.datalayer?.isRemoteLayer()) return
+
+    // The "endEdit" event is triggered at the end of an edition,
+    // and will trigger the sync.
+    // In the case of a deletion (or a change of layer), we don't want this
+    // event triggered to cause a sync event, as it would reintroduce
+    // deleted features.
+    // The `._marked_for_deletion` private property is here to track this status.
+    if (this._marked_for_deletion == true) {
+      this._marked_for_deletion = false
+      return
+    }
     this.sync.upsert(this.toGeoJSON())
   },
 
@@ -23,13 +34,10 @@ U.FeatureMixin = {
     return this.toGeoJSON().geometry
   },
 
-  syncDelete: function () {
-    this.sync.delete()
-  },
-
   initialize: function (map, latlng, options, id) {
     this.map = map
     this.sync = map.sync_engine.proxy(this)
+    this._mark_for_deletion = false
 
     if (typeof options === 'undefined') {
       options = {}
@@ -271,14 +279,12 @@ U.FeatureMixin = {
     }
     return false
   },
+
   del: function (sync) {
     this.isDirty = true
     this.map.closePopup()
     if (this.datalayer) {
-      this.datalayer.removeLayer(this)
-      this.disconnectFromDataLayer(this.datalayer)
-
-      if (sync !== false) this.syncDelete()
+      this.datalayer.removeLayer(this, sync)
     }
   },
 
@@ -321,7 +327,9 @@ U.FeatureMixin = {
       this.datalayer.isDirty = true
       this.datalayer.removeLayer(this)
     }
+
     datalayer.addLayer(this)
+    this.sync.upsert(this.toGeoJSON())
     datalayer.isDirty = true
     this._redraw()
   },
@@ -499,6 +507,7 @@ U.FeatureMixin = {
   onRemove: function (map) {
     this.parentClass.prototype.onRemove.call(this, map)
     if (this.map.editedFeature === this) {
+      this._marked_for_deletion = true
       this.endEdit()
       this.map.editPanel.close()
     }

umap/static/umap/js/umap.layer.js

@@ -896,8 +896,9 @@ U.DataLayer = L.Evented.extend({
     if (this.hasDataLoaded()) this.fire('datachanged')
   },
 
-  removeLayer: function (feature) {
+  removeLayer: function (feature, sync) {
     const id = L.stamp(feature)
+    if (sync !== false) feature.sync.delete()
     this.layer.removeLayer(feature)
     feature.disconnectFromDataLayer(this)
     this._index.splice(this._index.indexOf(id), 1)