Add XCTUnwrap(_:case:) test helper. (#95)

* Add XCTUnwrap(_:case:) test helper.

* wip

* wip

* wip

* wip

* wip

* wip

* wip

* wip

* wip

* wip

* Update Package.swift

* Update XCTUnwrap.swift

* Update XCTUnwrapTests.swift

* skip

* Update .github/workflows/ci.yml

* wip

* Update XCTUnwrap.swift

* Update Sources/CasePaths/XCTUnwrap.swift

Co-authored-by: Stephen Celis <stephen@stephencelis.com>

.github/workflows/ci.yml

@@ -13,32 +13,13 @@ concurrency:
  cancel-in-progress: true
 
 jobs:
- macos-11:
- name: MacOS 11
- runs-on: macos-11
+ macos-12:
+ name: MacOS 12
+ runs-on: macos-12
  strategy:
  matrix:
  xcode:
- - 12.5.1
- - '13.0'
- steps:
- - uses: actions/checkout@v2
- - name: Select Xcode ${{ matrix.xcode }}
- run: sudo xcode-select -s /Applications/Xcode_${{ matrix.xcode }}.app
- - name: Print Swift version
- run: swift --version
- - name: Run tests
- run: make test-swift
-
- macos-10-15:
- name: MacOS 10.15
- runs-on: macos-10.15
- strategy:
- matrix:
- xcode:
- - 11.3
- - 11.7
- - 12.4
+ - '14.2'
  steps:
  - uses: actions/checkout@v2
  - name: Select Xcode ${{ matrix.xcode }}

Makefile

@@ -5,16 +5,14 @@ test-linux:
  --rm \
  -v "$(PWD):$(PWD)" \
  -w "$(PWD)" \
- swift:5.3 \
+ swift:5.5 \
  bash -c 'make test-swift'
 
 test-swift:
  swift test \
- --enable-test-discovery \
  --parallel
  swift test \
  -c release \
- --enable-test-discovery \
  --parallel
 
 format:

Package.resolved

@@ -27,6 +27,15 @@
  "revision": "3303b164430d9a7055ba484c8ead67a52f7b74f6",
  "version": "1.0.0"
  }
+ },
+ {
+ "package": "xctest-dynamic-overlay",
+ "repositoryURL": "https://github.com/pointfreeco/xctest-dynamic-overlay.git",
+ "state": {
+ "branch": null,
+ "revision": "a9daebf0bf65981fd159c885d504481a65a75f02",
+ "version": "0.8.0"
+ }
  }
  ]
  },

Package.swift

@@ -1,27 +1,37 @@
-// swift-tools-version:5.2
+// swift-tools-version:5.5
 
 import PackageDescription
 
 let package = Package(
  name: "swift-case-paths",
+ platforms: [
+ .iOS(.v13),
+ .macOS(.v10_15),
+ .tvOS(.v13),
+ .watchOS(.v6),
+ ],
  products: [
  .library(
  name: "CasePaths",
  targets: ["CasePaths"]
  )
  ],
  dependencies: [
- .package(name: "Benchmark", url: "https://github.com/google/swift-benchmark", from: "0.1.0")
+ .package(name: "Benchmark", url: "https://github.com/google/swift-benchmark", from: "0.1.0"),
+ .package(url: "https://github.com/pointfreeco/xctest-dynamic-overlay", from: "0.8.0"),
  ],
  targets: [
  .target(
- name: "CasePaths"
+ name: "CasePaths",
+ dependencies: [
+ .product(name: "XCTestDynamicOverlay", package: "xctest-dynamic-overlay"),
+ ]
  ),
  .testTarget(
  name: "CasePathsTests",
  dependencies: ["CasePaths"]
  ),
- .target(
+ .executableTarget(
  name: "swift-case-paths-benchmark",
  dependencies: [
  "CasePaths",

Sources/CasePaths/XCTUnwrap.swift

@@ -0,0 +1,38 @@
+import Foundation
+@_spi(CurrentTestCase) import XCTestDynamicOverlay
+
+/// Asserts that an enum value matches a particular case and returns the associated value.
+///
+/// - Parameters:
+/// - expression: An enum value.
+/// - extract: A closure that attempts to extract a particular case from the enum. You can supply
+/// a case path literal here, like '/Enum.case'.
+/// - message: An optional description of a failure.
+/// - Returns: The unwrapped associated value from the matched case of the enum.
+public func XCTUnwrap<Root, Case>(
+ _ expression: @autoclosure () throws -> Root,
+ case extract: (Root) -> Case?,
+ _ message: @autoclosure () -> String = "",
+ file: StaticString = #file,
+ line: UInt = #line
+) throws -> Case {
+ guard let value = try extract(expression())
+ else {
+ #if canImport(ObjectiveC)
+ _ = XCTCurrentTestCase?.perform(Selector(("setContinueAfterFailure:")), with: false)
+ #endif
+ let message = message()
+ XCTFail(
+ """
+ XCTUnwrap failed: expected non-nil value of type "\(Case.self)"\
+ \(message.isEmpty ? "" : " - " + message)
+ """,
+ file: file,
+ line: line
+ )
+ throw UnwrappingCase()
+ }
+ return value
+}
+
+private struct UnwrappingCase: Error {}

Tests/CasePathsTests/XCTUnwrapTests.swift

@@ -0,0 +1,37 @@
+#if DEBUG && (os(iOS) || os(macOS) || os(tvOS) || os(watchOS))
+ import CasePaths
+ import XCTest
+
+ final class XCTUnwrapTests: XCTestCase {
+ func testXCTUnwrapFailure() throws {
+ try XCTSkipIf(ProcessInfo.processInfo.environment["CI"] != nil)
+
+ XCTExpectFailure {
+ $0.compactDescription == """
+ XCTUnwrap failed: expected non-nil value of type "Error"
+ """
+ }
+ _ = try XCTUnwrap(Result<Int, Error>.success(2), case: /Result.failure)
+ }
+
+ func testXCTUnwrapFailure_WithMessage() throws {
+ try XCTSkipIf(ProcessInfo.processInfo.environment["CI"] != nil)
+
+ XCTExpectFailure {
+ $0.compactDescription == """
+ XCTUnwrap failed: expected non-nil value of type "Error" - Should be success
+ """
+ }
+ _ = try XCTUnwrap(Result<Int, Error>.success(2), case: /Result.failure, "Should be success")
+ }
+
+ func testXCTUnwrapPass() throws {
+ try XCTSkipIf(ProcessInfo.processInfo.environment["CI"] != nil)
+
+ XCTAssertEqual(
+ try XCTUnwrap(Result<Int, Error>.success(2), case: /Result.success),
+ 2
+ )
+ }
+ }
+#endif