testWhenBatchFails_thenIntervalIncreases fails when expectation.fulfill called multiple times

Author: BennettSmith

Tests/ExportersTests/PersistenceExporter/Export/DataExportWorkerTests.swift

@@ -138,6 +138,7 @@ class DataExportWorkerTests: XCTestCase {
 
     func testWhenBatchFails_thenIntervalIncreases() {
         let delayChangeExpectation = expectation(description: "Export delay is increased")
+
         let mockDelay = MockDelay { command in
             if case .increase = command {
                 delayChangeExpectation.fulfill()
@@ -146,11 +147,20 @@ class DataExportWorkerTests: XCTestCase {
             }
         }
 
-        let exportExpectation = self.expectation(description: "value exported")
-        
+        let exportExpectation = expectation(description: "value exported")
+
+        // The onExport closure is called more than once as part of test execution
+        // It does not seem to be called the same number of times on each test run.
+        // Setting `assertForOverFulfill` to `false` works around the XCTestExpectation
+        // error that fails the test.
+        // "API violation - multiple calls made to -[XCTestExpectation fulfill] for value exported."
+        exportExpectation.assertForOverFulfill = false
+
         var mockDataExporter = DataExporterMock(exportStatus: .mockWith(needsRetry: true))
-        
-        mockDataExporter.onExport = { data in exportExpectation.fulfill() }
+
+        mockDataExporter.onExport = { data in
+            exportExpectation.fulfill()
+        }
 
         // When
         let fileReader = FileReaderMock()