[Telemetry] Bug fix in codedError.data from trackException() (#14191

)

* Bug fix

* Simplify fix, add unit test

* Change files

* Nit: change test description

change/@react-native-windows-telemetry-990667a5-918a-4348-8861-ce4ad8fc7a47.json

@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "Fix bug in error telemetry collection.",
+  "packageName": "@react-native-windows/telemetry",
+  "email": "[email protected]",
+  "dependentChangeType": "patch"
+}

packages/@react-native-windows/telemetry/src/e2etest/telemetry.test.ts

@@ -22,6 +22,18 @@ import * as errorUtils from '../utils/errorUtils';
 import * as projectUtils from '../utils/projectUtils';
 import * as versionUtils from '../utils/versionUtils';
 
+class CustomTestError extends Error {
+  // Declare a mock errno field, so it is picked up by trackException() (see syscallExceptionFieldsToCopy)
+  // to copy it into codedError.data.
+  errno: string;
+
+  constructor(message: string) {
+    super(message);
+    this.name = 'CustomTestError';
+    this.errno = '123';
+  }
+}
+
 export class TelemetryTest extends Telemetry {
   protected static hasTestTelemetryProviders: boolean;
   protected static testTelemetryProvidersRan: boolean;
@@ -391,8 +403,16 @@ function verifyTestCommandTelemetryProcessor(
             : 'Unknown',
         );
 
+        // If the exception type is not CodedError but any data got copied into envelope.CodedError.data,
+        // for instance autolinking error info, build the expected CodedError.data.
+        let expectedCodedErrorData = {};
+        if (expectedError instanceof CustomTestError) {
+          expectedCodedErrorData = {errno: expectedError.errno};
+        }
+
         expect(codedError.data).toStrictEqual(
-          (expectedError as errorUtils.CodedError).data ?? {},
+          (expectedError as errorUtils.CodedError).data ??
+            expectedCodedErrorData,
         );
       } else {
         // If this is not error scenario, it must be a command successful event.
@@ -694,3 +714,29 @@ test.each(testTelemetryOptions)(
     });
   },
 );
+
+test.each(testTelemetryOptions)(
+  'A custom Error-based object with MS Build error info is copied into codedError.data appropriately by trackException()',
+  async options => {
+    await TelemetryTest.startTest(options);
+
+    const expectedError = new CustomTestError('some message');
+
+    // AI eats errors thrown in telemetry processors
+    const caughtErrors: Error[] = [];
+    TelemetryTest.addTelemetryInitializer(
+      verifyTestCommandTelemetryProcessor(
+        caughtErrors,
+        'Unknown',
+        expectedError,
+      ),
+    );
+
+    await runTestCommandE2E(() => testCommandBody(expectedError));
+
+    TelemetryTest.endTest(() => {
+      // Check if any errors were thrown
+      expect(caughtErrors).toHaveLength(0);
+    });
+  },
+);

packages/@react-native-windows/telemetry/src/telemetry.ts

@@ -463,7 +463,7 @@ export class Telemetry {
     const syscallExceptionFieldsToCopy = ['errno', 'syscall', 'code'];
     for (const f of syscallExceptionFieldsToCopy) {
       if ((error as any)[f]) {
-        codedErrorStruct.data.codedError.data[f] = (error as any)[f];
+        codedErrorStruct.data[f] = (error as any)[f];
       }
     }