[Darwin] Fix for MTRDevice attribute report omitting errors (#26592)

Author: jtung-apple

src/darwin/Framework/CHIP/MTRDevice.mm

@@ -912,7 +912,8 @@ - (NSArray *)_getAttributesToReportWithReportedValues:(NSArray<NSDictionary<NSSt
         NSError * attributeError = attributeReponseValue[MTRErrorKey];
 
         // sanity check either data value or error must exist
-        if (!attributeDataValue && attributeError) {
+        if (!attributeDataValue && !attributeError) {
+            MTR_LOG_INFO("%@ report %@ no data value or error: %@", self, attributePath, attributeReponseValue);
             continue;
         }
 

src/darwin/Framework/CHIPTests/MTRDeviceTests.m

@@ -1506,6 +1506,19 @@ - (void)test017_TestMTRDeviceBasics
     // nonexistent attribute
     [self waitForExpectations:@[ expectedValueReportedExpectation, expectedValueRemovedExpectation ] timeout:5 enforceOrder:YES];
 
+    // Test if errors are properly received
+    XCTestExpectation * attributeReportErrorExpectation = [self expectationWithDescription:@"Attribute read error"];
+    delegate.onAttributeDataReceived = ^(NSArray<NSDictionary<NSString *, id> *> * data) {
+        for (NSDictionary<NSString *, id> * attributeReponseValue in data) {
+            if (attributeReponseValue[MTRErrorKey]) {
+                [attributeReportErrorExpectation fulfill];
+            }
+        }
+    };
+    // use the nonexistent attribute and expect read error
+    [device readAttributeWithEndpointID:testEndpointID clusterID:testClusterID attributeID:testAttributeID params:nil];
+    [self waitForExpectations:@[ attributeReportErrorExpectation ] timeout:10];
+
     // reset the onAttributeDataReceived to validate the following resubscribe test
     delegate.onAttributeDataReceived = ^(NSArray<NSDictionary<NSString *, id> *> * data) {
         attributeReportsReceived += data.count;