fix(SyncProcess): Apply skipErroneousActions broadly

to handle actions with missing mappings in the next sync run

Signed-off-by: Marcel Klehr <mklehr@gmx.net>

Author: marcelklehr

src/lib/Diff.ts

@@ -334,6 +334,16 @@ export default class Diff<
             targetLocation
           )
           if (action.type !== ActionType.CREATE && typeof action.payload.id !== 'undefined' && typeof newAction.payload.id === 'undefined') {
+            if (skipErroneousActions) {
+              // The action references an item that has no counterpart on the target, so it
+              // can't be applied (e.g. a MOVE of an item that no longer exists there). Drop
+              // it rather than throwing — the alternative (MappingFailureError) triggers a
+              // reset-cache + forceSync recovery that re-applies already-committed actions
+              // and duplicates them on non-atomic servers. A subsequent sync reconciles the
+              // item afresh if it's still relevant.
+              Logger.log('Failed to map id: ' + action.payload.id + ' — dropping action from plan as no longer valid')
+              return
+            }
             Logger.log(
               'payload.location = ' +
               action.payload.location +

src/lib/strategies/Default.ts

@@ -437,7 +437,10 @@ export default class SyncProcess {
       this.planStage3Server = {
         CREATE: this.serverPlanStage2.CREATE,
         UPDATE: this.serverPlanStage2.UPDATE,
-        MOVE: this.serverPlanStage2.MOVE.map(mappingsSnapshot, ItemLocation.SERVER),
+        // skipErroneousActions: a MOVE whose item can no longer be mapped to the target is
+        // unapplyable; drop it instead of throwing MappingFailureError (which would force a
+        // cache reset + from-scratch resync that duplicates on non-atomic servers).
+        MOVE: this.serverPlanStage2.MOVE.map(mappingsSnapshot, ItemLocation.SERVER, () => true, true),
         REMOVE: this.serverPlanStage2.REMOVE,
         REORDER: this.serverPlanStage2.REORDER,
       }
@@ -471,7 +474,8 @@ export default class SyncProcess {
       this.planStage3Local = {
         CREATE: this.localPlanStage2.CREATE,
         UPDATE: this.localPlanStage2.UPDATE,
-        MOVE: this.localPlanStage2.MOVE.map(mappingsSnapshot, ItemLocation.LOCAL),
+        // skipErroneousActions: see the server stage 3 plan above.
+        MOVE: this.localPlanStage2.MOVE.map(mappingsSnapshot, ItemLocation.LOCAL, () => true, true),
         REMOVE: this.localPlanStage2.REMOVE,
         REORDER: this.localPlanStage2.REORDER,
       }
@@ -539,13 +543,21 @@ export default class SyncProcess {
         mappingsSnapshot
       )
 
+      // skipErroneousActions: a REORDER targeting a folder that can no longer be mapped is
+      // moot (the folder was moved/removed); drop it instead of throwing MappingFailureError,
+      // which would force a cache reset + from-scratch resync that duplicates on non-atomic
+      // servers.
       this.localReorders = localReorders3.map(
         mappingsSnapshot,
-        ItemLocation.LOCAL
+        ItemLocation.LOCAL,
+        () => true,
+        true
       )
       this.serverReorders = serverReorders3.map(
         mappingsSnapshot,
-        ItemLocation.SERVER
+        ItemLocation.SERVER,
+        () => true,
+        true
       )
     }