Change Counter update object to have amount property instead of inc

`amount` is more suitable in this case as the value can be negative in
case the counter was decremented.

Resolves PUB-1540

Author: VeskeR

README.md

@@ -747,11 +747,11 @@ await root.remove('name');
 
 await counter.increment(5);
 // LiveCounter new value: 5
-// LiveCounter update details: { update: { inc: 5 } }
+// LiveCounter update details: { update: { amount: 5 } }
 
 await counter.decrement(2);
 // LiveCounter new value: 3
-// LiveCounter update details: { update: { inc: -2 } }
+// LiveCounter update details: { update: { amount: -2 } }
 ```
 
 You can deregister subscription listeners as follows:

ably.d.ts

@@ -2415,7 +2415,7 @@ export declare interface LiveCounterUpdate extends LiveObjectUpdate {
     /**
      * The value by which the counter was incremented or decremented.
      */
-    inc: number;
+    amount: number;
   };
 }
 

src/plugins/objects/livecounter.ts

@@ -8,7 +8,7 @@ export interface LiveCounterData extends LiveObjectData {
 }
 
 export interface LiveCounterUpdate extends LiveObjectUpdate {
-  update: { inc: number };
+  update: { amount: number };
 }
 
 export class LiveCounter extends LiveObject<LiveCounterData, LiveCounterUpdate> {
@@ -291,7 +291,7 @@ export class LiveCounter extends LiveObject<LiveCounterData, LiveCounterUpdate>
 
   protected _updateFromDataDiff(prevDataRef: LiveCounterData, newDataRef: LiveCounterData): LiveCounterUpdate {
     const counterDiff = newDataRef.data - prevDataRef.data;
-    return { update: { inc: counterDiff } };
+    return { update: { amount: counterDiff } };
   }
 
   protected _mergeInitialDataFromCreateOperation(stateOperation: StateOperation): LiveCounterUpdate {
@@ -302,7 +302,7 @@ export class LiveCounter extends LiveObject<LiveCounterData, LiveCounterUpdate>
     this._dataRef.data += stateOperation.counter?.count ?? 0;
     this._createOperationIsMerged = true;
 
-    return { update: { inc: stateOperation.counter?.count ?? 0 } };
+    return { update: { amount: stateOperation.counter?.count ?? 0 } };
   }
 
   private _throwNoPayloadError(op: StateOperation): void {
@@ -332,6 +332,6 @@ export class LiveCounter extends LiveObject<LiveCounterData, LiveCounterUpdate>
 
   private _applyCounterInc(op: StateCounterOp): LiveCounterUpdate {
     this._dataRef.data += op.amount;
-    return { update: { inc: op.amount } };
+    return { update: { amount: op.amount } };
   }
 }

test/package/browser/template/src/index-objects.ts

@@ -57,7 +57,7 @@ globalThis.testAblyPackage = async function () {
   // same deal with nullish coalescing
   const value: number = counter?.value()!;
   const counterSubscribeResponse = counter?.subscribe(({ update }) => {
-    const shouldBeANumber: number = update.inc;
+    const shouldBeANumber: number = update.amount;
   });
   counterSubscribeResponse?.unsubscribe();
 

test/realtime/objects.test.js

@@ -778,7 +778,7 @@ define(['ably', 'shared_helper', 'chai', 'objects', 'objects_helper'], function
               root.get('counter').subscribe((update) => {
                 try {
                   expect(update).to.deep.equal(
-                    { update: { inc: -1 } },
+                    { update: { amount: -1 } },
                     'Check counter subscription callback is called with an expected update object after STATE_SYNC sequence with "tombstone=true"',
                   );
                   resolve();
@@ -1776,7 +1776,7 @@ define(['ably', 'shared_helper', 'chai', 'objects', 'objects_helper'], function
               root.get('counter').subscribe((update) => {
                 try {
                   expect(update).to.deep.equal(
-                    { update: { inc: -1 } },
+                    { update: { amount: -1 } },
                     'Check counter subscription callback is called with an expected update object after OBJECT_DELETE operation',
                   );
                   resolve();
@@ -3567,7 +3567,7 @@ define(['ably', 'shared_helper', 'chai', 'objects', 'objects_helper'], function
               counter.subscribe((update) => {
                 try {
                   expect(update).to.deep.equal(
-                    { update: { inc: 1 } },
+                    { update: { amount: 1 } },
                     'Check counter subscription callback is called with an expected update object for COUNTER_INC operation',
                   );
                   resolve();
@@ -3604,7 +3604,7 @@ define(['ably', 'shared_helper', 'chai', 'objects', 'objects_helper'], function
                 try {
                   const expectedInc = expectedCounterIncrements[currentUpdateIndex];
                   expect(update).to.deep.equal(
-                    { update: { inc: expectedInc } },
+                    { update: { amount: expectedInc } },
                     `Check counter subscription callback is called with an expected update object for ${currentUpdateIndex + 1} times`,
                   );