[SE-0025] Adapt accessibility for fileprivate

Sources/XCTest/Private/PerformanceMeter.swift

@@ -91,7 +91,7 @@ public final class PerformanceMeter {
         return state == .measurementFinished || state == .measurementAborted
     }
 
-    private enum State {
+    fileprivate enum State {
         case iterationUnstarted
         case iterationStarted
         case iterationFinished

Sources/XCTest/Private/PrintObserver.swift

@@ -66,7 +66,7 @@ internal class PrintObserver: XCTestObservation {
         return formatter
     }()
 
-    private func printAndFlush(_ message: String) {
+    fileprivate func printAndFlush(_ message: String) {
         print(message)
         fflush(stdout)
     }

Sources/XCTest/Private/TestFiltering.swift

@@ -47,12 +47,12 @@ internal struct TestFiltering {
 }
 
 /// A selected test can be a single test case, or an entire class of test cases
-private struct SelectedTest {
+fileprivate struct SelectedTest {
     let testCaseClassName: String
     let testCaseMethodName: String?
 }
 
-private extension SelectedTest {
+fileprivate extension SelectedTest {
     init?(selectedTestName: String) {
         let components = selectedTestName.characters.split(separator: "/").map(String.init)
         switch components.count {

Sources/XCTest/Private/WallClockTimeMetric.swift

@@ -67,7 +67,7 @@ internal final class WallClockTimeMetric: PerformanceMetric {
 }
 
 
-private extension Collection where Index: IntegerLiteralConvertible, Iterator.Element == WallClockTimeMetric.Measurement {
+fileprivate extension Collection where Index: IntegerLiteralConvertible, Iterator.Element == WallClockTimeMetric.Measurement {
     var average: WallClockTimeMetric.Measurement {
         return self.reduce(0, combine: +) / Double(count.toIntMax())
     }

Sources/XCTest/Public/XCTAssert.swift

@@ -10,7 +10,7 @@
 //  XCTAssert.swift
 //
 
-private enum _XCTAssertion {
+fileprivate enum _XCTAssertion {
     case equal
     case equalWithAccuracy
     case greaterThan
@@ -46,7 +46,7 @@ private enum _XCTAssertion {
     }
 }
 
-private enum _XCTAssertionResult {
+fileprivate enum _XCTAssertionResult {
     case success
     case expectedFailure(String?)
     case unexpectedFailure(ErrorProtocol)

Sources/XCTest/Public/XCTestObservationCenter.swift

@@ -88,7 +88,7 @@ public class XCTestObservationCenter {
     }
 }
 
-private extension XCTestObservation {
+fileprivate extension XCTestObservation {
     var wrapper: ObjectWrapper<XCTestObservation> {
         return ObjectWrapper(object: self, objectIdentifier: ObjectIdentifier(self))
     }