Xcode 12.5 Beta Release Notes

Update your apps to use new features, and test your apps against API changes.

Overview

Xcode 12.5 Beta includes SDKs for iOS 14.5, iPadOS 14.5, tvOS 14.5, watchOS 7.4, and macOS Big Sur 11.3. The Xcode 12.5 Beta release supports on-device debugging for iOS 9 and later, tvOS 9 and later, and watchOS 2 and later. Xcode 12.5 Beta requires a Mac running macOS Big Sur 11 or later.

General

New Features

• The Reveal Build Products Folder item in the Product menu reveals the build products directory in Finder. (72248847)

Resolved Issues

• Fixed an issue where code completion, live issues, and other code-analysis features could produce incorrect results after a user moves a source file while an Xcode project is open. (57054858)

• Large workspaces now open faster. (70276306)

Apple Clang Compiler

New Features

• The _LIBCPP_RAW_ITERATORS macro has been removed from libc++ in favor of using wrapped iterators. (63088925)

Build System

New Features

• The build system no longer re-signs the hosting app target when building app-hosted test targets; instead it builds test targets before the app target’s sign task runs. This eliminates an extra codesign task, which speeds up builds for large apps with such test targets. (47322098)

• xcodebuild now supports the -archive flag when creating an XCFramework, providing a shorthand method for creating an XCFramework from one or more archives. (64725832)

  For example:

  xcodebuild -archive <archive_path1> -framework MyFramework.framework -archive <archive_path2> -framework MyFramework.framework -o <output_xcframework_path>
  

Known Issues

• Builds where Parallelize Build is turned off may hit a new dependency cycle when a hosted test target, which defines the TEST_HOST build setting, depends on targets other than the target that produces the host bundle (the one to which TEST_HOST refers). (73210420)

  Workaround: Turn on Parallelize Build in the scheme. If it’s not possible to turn on Parallelize Build, then in the Dependencies build phase of the hosted test target, move the target that produces the host bundle to the end of the list.

Resolved Issues

• The copy files build phase now properly signs code for embedded frameworks with a framework version that isn’t “A”. (55701162) (FB7323980)

• You can now manually reorder schemes. (61456142)

• xcodebuild no longer double-escapes the output of xcodebuild -showBuildSettings -json. (63554669)

• Preprocess and Assemble single-file actions now work correctly when analyze-while-building is enabled, and no longer display an empty property list in the source editor. (70811963)

Code Completion

New Features

• Code completion is more reliable in expressions that contain errors, and in expressions that are ambiguous without additional context. (71378252)

  For example, given:

  func test(a: Int, b: String) -> Int { ... }
  func test(a: Int, b: Int) -> String { ... }
  func test(a: (Int, Int) -> Int) -> Int { ... }
  

  Invoking code completion after test().prefix(3). suggests members of String. Invoking code completion after test(a: 2). suggests members of Int and String. Invoking code completion after $0. in the following block suggests members of Int:

  test {
    $0.
  }
  

Debugging

New Features

• When debugging C++ programs using libc++, LLDB now offers improved expression evaluation support for STL containers and algorithms.

  • You can call member functions of STL containers, even if they are never called in the target program.

  • LLDB can instantiate templated functions from the standard library. This includes algorithms such as std::sort, std::count, std::count_if, etc. (19866497)

Known Issues

• Xcode fails to launch apps when Nightstand Mode is enabled on Apple Watch. (61351690)

  Workaround: Disable Nightstand Mode by going to Settings > General > Nightstand Mode and toggling the switch off.

Instruments

New Features

• <(start|end)-pattern> elements in os-signpost-interval schema are now optional. This allows Custom Instruments to match signposts by name and other properties without needing to specify the expected message format. (43850670)

• Profiling XCTest with Instruments now automatically starts the recording, without a click on the record button. (50260328)

• Instruments can now import os_log and os_signpost data from the ktrace files that include logging-level data. (56037733)

• Custom Instruments can now specify statically defined sub-tracks without needing to be driven by table column data. (61367995)

• xctrace export now produces output in time-sorted order. (69804348)

• Table of Contents query for xctrace now exposes metadata information about the run. (71320853)

Resolved Issues

• Fixed an issue where xctrace wouldn’t pass a standard input to the launched process. (17842765)

• Fixed an issue where plot elements wouldn’t draw using the color column specified in a point schema. (71680467) (FB8913696)

Interface Builder

New Features

• You can now configure a Module for custom classes in the inspector for NSObjectController and similar objects. (35971498)

Resolved Issues

• NSButton’s “Image Only” Position setting now properly displays an image without a title at runtime. (16200971)

• Fixed an issue where the assistant editor wouldn’t display source code for a selected object’s custom Swift class if the class was annotated with @objc. (19623315)

• Fixed an issue where connect-to-source wouldn’t properly escape Swift keywords in Outlet and Action names. (22527929)

• Fixed an issue where Editor > Debug Selected Views failed to attach to @IBDesignable views for debugging. (45217745) (FB5645911)

• Added Dark Mode support for the connect-to-source bindings popover. (47583413) (FB5701084)

• Fixed iOS canvas appearance issues when importing project images with an unexpected scale. (63789933) (FB7719276)

• Fixed an issue where the assistant editor could open the wrong source file for a selected object’s custom class if duplicate class names existed in the project. (67362709)

• Fixed the canvas drifting when resizing the document outline. (67505701)

• Fixed an issue where selecting the custom color item from an inspector’s color popup menu wouldn’t open the system colors picker window. (69365980) (FB8727901)

• Selecting a view in the canvas and performing Select All (CMD+A) no longer selects the view’s layout guides. (69518746)

• Fixed an issue where certain connect-to-source popover labels didn’t show up in Dark Mode. (69713404)

• Fixed an issue where the custom colors swatch in an inspector’s color properties displayed an incorrectly offset focus indicator. (72370447)

Localization

New Features

• You can now use Xcode to localize applications into all ISO 639 languages. (46806165) (FB5359472)

• You can now use workspaces to export a collection of projects for localization, generating a single localization catalog for all projects in the workspace. As part of this change, options to import and export for localization are now in the Product menu instead of the Editor menu. You can also use xcodebuild -importLocalizations and xcodebuild -exportLocalizations with the -workspace option to export or import a workspace. (48548375)

• The new Localization Export Supported build setting lets you disable localization export for a specific target or project that doesn’t require localization. (66606145)

Resolved Issues

• Fixed an issue where the Application Language menu in the scheme editor doesn’t show all languages for which a project is localized. (28872507)

• *-InfoPlist.strings files are now renamed to InfoPlist.strings at build-time for bundles that require Info.plist localization. This is consistent with existing behavior that renames Info.plist files at build-time. (38686398)

• Exporting and importing for localization now produces an error if two files (ex: Main.strings and Main.storyboard) write translations to the same path. (39917359, 52412470) (FB6384066)

• Fixed an issue where exporting color sets for localization caused Xcode to crash (63934393)

• Fixed an issue where new-style multiline Swift string literals weren’t properly extracted for localization. (64652467) (FB7742731)

• Localizable keys in Info.plist files are now only automatically extracted on localization export for Application and App Extension targets. (66871236)

• Fixed an issue where strings were replaced with their keys at localization export if the .strings file was outside the directory hierarchy of the Xcode project. (69835864) (FB8761502)

Playgrounds

New Features

• A Playground in an app’s project can now access symbols from the app target. New playgrounds you create have this option on by default. To enable this functionality in existing playground documents, turn on the Import App Types option in the File Inspector. (66357893)

• Inline results for deeply nested Swift arrays and structs now display more information in Xcode Playgrounds. (67344623)

Resolved Issues

• Fixed an issue that could cause Xcode to show “No editor” when opening a Playground. (56484197)

Signing and Distribution

Known Issues

• When attempting to export a distribution certificates from Xcode, keyboard input may fail in the authentication field, making it impossible to authenticate with a password. (71011727) (FB8880845)

  Workaround: Export the certificate and private key using Keychain Access.

Simulator

New Features

• Simulator now supports recording video from within the app. Hold Option when clicking on the screenshot button in the toolbar (or press Command+R) to record a video. Click the red button to stop video recording. (63041314)

• Simulator can create animated GIFs from video recordings using the new Record Video feature. After recording a video, right-click on the video preview, then select Save as Animated GIF. To keep both the video file and the animated GIF, press and hold Option and select Save Copy as Animated GIF. You can adjust the dimensions and size of the generated GIFs in Simulator Preferences. (65089299)

Known Issues

• Apps that use WKWebView may crash in simulated devices running iOS 13.7 or earlier on a Mac with Apple silicon. (73375522)

Source Control

Resolved Issues

• Fixed an issue where some workspaces could fail to notice project file changes from source control operations until you quit and relaunched Xcode. (3920347)

StoreKit

New Features

• StoreKit Testing in Xcode now supports testing of non-renewing subscriptions. (59478394)

• The StoreKit Test framework is now availabe on watchOS. (68152552)

Swift

New Features

• Incremental compilation is faster in many cases. When you change code within the body of a struct, class, enum, protocol, or extension, Swift now recompiles far fewer files in that module than before. (51230617)

• Implicit member expressions now support chains of member accesses. (57295228)

  For example, this code is now valid:

  let milky: UIColor = .white.withAlphaComponent(0.5)
  let milky2: UIColor = .init(named: "white")!.withAlphaComponent(0.5)
  let milkyChance: UIColor? = .init(named: "white")?.withAlphaComponent(0.5)
  

  As is the case with the existing implicit member expression syntax, the resulting type of the chain must be the same as the (implicit) base, so it isn’t well-formed to write let cgMilky: CGColor = .white.withAlphaComponent(0.5).cgColor (unless appropriate white and withAlphaComponent members were defined on CGColor.).

  Members of a “chain” can be properties, method calls, subscript accesses, force unwraps, or optional chaining question marks. Furthermore, the type of each member along the chain is permitted to differ (again, as long as the base of the chain matches the resulting type) meaning the following successfully typechecks:

  struct Foo {
    static var foo = Foo()
    static var bar = Bar()
  
    var anotherFoo: Foo { Foo() }
    func getFoo() -> Foo { Foo() }
    var optionalFoo: Foo? { Foo() }
    subscript() -> Foo { Foo() }
  }
  
  struct Bar {
    var anotherFoo = Foo()
  }
  
  let _: Foo? = .bar.anotherFoo.getFoo().optionalFoo?.optionalFoo![]
  

• Swift includes more checks when bridging data from Objective-C. In particular, the runtime library aborts your program with a suitable error message if it detects a non-nullable pointer that contains a null value. (58650899)

• Property wrappers are now supported on local variables. (73377111)

• Functions, subscripts, and initializers may now have more than one variadic parameter, as long as all parameters that follow variadic parameters are labeled. (73676506)

  This makes declarations like the following valid:

  func foo(_ a: Int..., b: Double...) { }
  
  struct Bar {
    subscript(a: Int..., b b: Int...) -> [Int] { a + b }
  
    init(a: String..., b: Float...) { }
  }
  

Resolved Issues

• Function overloading now works in local contexts, making the following valid:

  func outer(x: Int, y: String) {
    func doIt(_: Int) {}
    func doIt(_: String) {}
  
    doIt(x)
    doIt(y)
  }
  

  In this code, the first doIt(_:) calls with an Int value, and the second with a String value. (29312676)

• The runtime and compiler support for Swift’s is, as?, and as! operators has been overhauled, providing more consistent and predictable behavior. (58991956)

• If your app (including loaded OS binaries) contains multiple redundant protocol conformances, Swift now uses the first one it finds in the first binary loaded (including in OS binaries). (72049977)

Swift Packages

New Features

• Swift packages that specify a 5.4 tools version can now explicitly declare targets as executable, which allows the use of the @main keyword in package code. (SE-0294, 47691185)

• Swift Package Manager caches package dependencies on a per-user basis, which reduces the amount of network traffic and increases performance of dependency resolution for subsequent uses of the same package. If needed, you can disable cache use in xcodebuild by using the new -disablePackageRepositoryCache flag. (72204929)

Testing

New Features

• XCTest now supports marking test failures as “expected”. Expected test failures don’t impact the overall pass/fail result of the suite containing the test. Xcode displays expected failures differently in the Test Navigator and Test Report, and highlights the line of code where the expected failure occurred along with an optional user description. Expected test failures provide a low-overhead tool for preserving the overall “green” state of a project’s test suite when there are failures which can’t be immediately resolved, ensuring that any new failures are clearly visible. In contrast to skipping a test with XCTSkip, a test with an expected failure still runs, reporting any unexpected changes. (13408632)

  To mark a failure as expected, call the new XCTExpectFailure API in a test before the code which produces the test failure, for example:

  XCTExpectFailure("…")
  // Perform test which currently fails
  

  Additionally, the scope of the expected failure can be limited by enclosing the failing code in a closure:

  // Arrange and act on the test subject
  
  XCTExpectFailure("…") {
      XCTAssert(…) // Failing assertion
  }
  
  // Continue test with further assertions etc.
  

  By default, if XCTExpectFailure is called but the test doesn’t record a failure, XCTest marks the test as having failed due to an “unmatched expected failure”. This can be suppressed for failures which occur non-deterministically, by passing XCTExpectFailure an XCTExpectedFailure.Options object as a parameter, with its isStrict property set to false:

  let options = XCTExpectedFailure.Options()
  options.isStrict = false
  XCTExpectFailure("…", options: options)
  // Perform test which sometimes fails
  

• Xcode now allows you to clean test results without having to re-open your workspace by selecting Clean Test Results from Xcode’s Product menu. (16527161)

• Xcode now supports XCTest unit and UI tests for watchOS apps. When creating a new watchOS app, check the Include tests checkbox to add a unit and UI test target to the newly created project. For an existing project, add a unit or UI test target via File > New > Target, and then add the test target to the Test action of the WatchKit App scheme. To run the tests, select a watch simulator or device from the run destinations menu in the toolbar, and then choose Product > Test. Note that testing is supported on watchOS 7.4 or later. (21395998)

• XCTest now automatically includes specialized subclasses of Swift generic test classes when running tests on macOS 11.3, iOS 14.5, tvOS 14.5, watchOS 7.4, or later OS versions. This allows you to use generics to improve reusability of test classes. (23493200)

• XCTest now includes XCTAssertIdentical(_:_:_:file:line:) and XCTAssertNotIdentical(_:_:_:file:line:) APIs to assert whether two object instances are identical (the same instance) and are stricter than XCTAssertEqual by using the === operator instead of == in Swift. (46137782)

Known Issues

• XCTest’s legacy Swift overlay library (libswiftXCTest.dylib) has been removed. Don’t use this library; instead use its replacement, libXCTestSwiftSupport.dylib. Any frameworks that link XCTest and encounter build issues due to this removed legacy library need to replace their manual framework or library search paths with the build setting ENABLE_TESTING_SEARCH_PATHS=YES, which automatically configures a target with the search paths needed to locate XCTest libraries. (70365050)

• XCTOSSignpostMetric’s methods unexpectedly throw an exception on watchOS. (72552791)

• XCUIElement’s adjust(toNormalizedSliderPosition:) method may adjust to the wrong value for sliders in Watch apps. (73100059)

• When a test target has Automatically include new tests disabled in a test plan or scheme, and tests for that test plan or scheme are run via xcodebuild test-without-building, each of the selected tests may run twice, which may lead to longer overall run times or timeouts in CI environments. (73230328)

  Workaround: Enable Automatically include new tests for affected test targets, or use test instead of test-without-building.

• UI tests running on iOS devices that use the arm64e architecture (including iPhone XS and later) fail to launch with a Symbol not found error. (73263692)

  Workaround: In the Xcode build settings for affected UI test targets, under Other Swift Flags (OTHER_SWIFT_FLAGS), add -runtime-compatibility-version none.

• Running specific test methods or classes written in Swift using the xctest or swift test command line tools doesn’t work on Apple platforms if those classes don’t explicitly customize their ObjC name using @objc(...). (73267118)

  Workaround: Run the entire test bundle, or customize affected classes’ names using @objc(...).

• When running unit tests for a Watch app, the tests may sometimes fail to start after the app has launched. (73478326)

  Workaround: Run the test again, or close the simulated device and try again.

Resolved Issues

• The message String parameter of XCTSkip.init(_:file:line:) no longer includes @autoclosure incorrectly. Unlike its conditional variants XCTSkipIf and XCTSkipUnless, XCTSkip’s initializer unconditionally evaluates its message string. (63827685)

• If a test times out (due to having Test Timeouts enabled in the active Test Plan), any content that the test emitted to standard out or standard error prior to the timeout is now included in the test log. (64591225)

• Xcode and xcodebuild now prevent the computer from sleeping while executing tests. (67493488)

• If code under test crashes, and Xcode is able to collect a crash report, the error message that Xcode generates in the Test Report and Test Log includes the crashing symbol, as well as the Application Specific Information field from the crash report. (69755517)