Ensure tests representing containing types of suite types are synthesized if necessary

Resolves rdar://127770218

Author: stmontgomery

Sources/Testing/Parameterization/TypeInfo.swift

@@ -276,11 +276,15 @@ extension TypeInfo {
     }
     return nil
   }
+}
 
-  /// A sequence of instances of this type representing the types that
-  /// recursively contain it, starting with the immediate parent (if any.)
-  var allContainingTypeInfo: some Sequence<Self> {
-    sequence(first: self, next: \.containingTypeInfo).dropFirst()
+extension Test {
+  /// A sequence of ``TypeInfo`` instances representing the types that
+  /// recursively contain this test, if any.
+  var allContainingTypeInfo: some Sequence<TypeInfo> {
+    sequence(first: containingTypeInfo) { element in
+      element?.containingTypeInfo
+    }.compactMap { $0 }
   }
 }
 

Sources/Testing/Test+Discovery.swift

@@ -80,32 +80,23 @@ extension Test {
   ///
   /// - Parameters:
   ///   - tests: A dictionary of tests to amend.
-  ///
-  /// - Returns: The number of key-value pairs added to `tests`.
-  @discardableResult private static func _synthesizeSuiteTypes(into tests: inout [ID: Self]) -> Int {
-    let originalCount = tests.count
-
-    // Find any instances of Test in the input that are *not* suites. We'll be
-    // checking the containing types of each one.
-    for test in tests.values where !test.isSuite {
-      guard let suiteTypeInfo = test.containingTypeInfo else {
-        continue
-      }
-      let suiteID = ID(typeInfo: suiteTypeInfo)
-      if tests[suiteID] == nil {
-        tests[suiteID] = Test(traits: [], sourceLocation: test.sourceLocation, containingTypeInfo: suiteTypeInfo, isSynthesized: true)
-
-        // Also synthesize any ancestral suites that don't have tests.
-        for ancestralSuiteTypeInfo in suiteTypeInfo.allContainingTypeInfo {
-          let ancestralSuiteID = ID(typeInfo: ancestralSuiteTypeInfo)
-          if tests[ancestralSuiteID] == nil {
-            tests[ancestralSuiteID] = Test(traits: [], sourceLocation: test.sourceLocation, containingTypeInfo: ancestralSuiteTypeInfo, isSynthesized: true)
-          }
+  private static func _synthesizeSuiteTypes(into tests: inout [ID: Self]) {
+    // We won't have an accurate source location for synthesized suites, so use
+    // a "runtime inferred" sentinel value instead.
+    //
+    // FIXME: Consider either changing `Test.sourceLocation` to Optional (an
+    // API-breaking change) or modifying Runner.Plan so that it doesn't require
+    // an actual Test instance to represent synthesized parent suites.
+    lazy var inferredSourceLocation = SourceLocation(fileID: "<runtime-inferred>", filePath: "<runtime-inferred>", line: 0, column: 0)
+
+    for test in tests.values {
+      for ancestorTypeInfo in test.allContainingTypeInfo {
+        let ancestorSuiteID = ID(typeInfo: ancestorTypeInfo)
+        if tests[ancestorSuiteID] == nil {
+          tests[ancestorSuiteID] = Test(traits: [], sourceLocation: inferredSourceLocation, containingTypeInfo: ancestorTypeInfo)
         }
       }
     }
-
-    return tests.count - originalCount
   }
 }
 

Sources/Testing/Test.swift

@@ -192,29 +192,18 @@ public struct Test: Sendable {
     containingTypeInfo != nil && testCasesState == nil
   }
 
-  /// Whether or not this instance was synthesized at runtime.
-  ///
-  /// During test planning, suites that are not explicitly marked with the
-  /// `@Suite` attribute are synthesized from available type information before
-  /// being added to the plan. For such suites, the value of this property is
-  /// `true`.
-  @_spi(ForToolsIntegrationOnly)
-  public var isSynthesized = false
-
   /// Initialize an instance of this type representing a test suite type.
   init(
     displayName: String? = nil,
     traits: [any Trait],
     sourceLocation: SourceLocation,
     containingTypeInfo: TypeInfo,
-    isSynthesized: Bool = false
   ) {
     self.name = containingTypeInfo.unqualifiedName
     self.displayName = displayName
     self.traits = traits
     self.sourceLocation = sourceLocation
     self.containingTypeInfo = containingTypeInfo
-    self.isSynthesized = isSynthesized
   }
 
   /// Initialize an instance of this type representing a test function.

Tests/TestingTests/PlanTests.swift

@@ -421,6 +421,15 @@ struct PlanTests {
     #expect(plan.stepGraph.subgraph(at: typeInfo.fullyQualifiedNameComponents + CollectionOfOne("reserved1(reserved2:)")) != nil)
   }
 
+  @Test("Ancestor suite types without @Suite are synthesized")
+  func ancestorSuiteSynthesis() async {
+    let plan = await Runner.Plan(selecting: OutermostSuite.self)
+    let testNames = plan.steps.map(\.test.name)
+    #expect(testNames.contains("OutermostSuite"))
+    #expect(testNames.contains("ChildSuite"))
+    #expect(testNames.contains("example()"))
+  }
+
 #if !SWT_NO_SNAPSHOT_TYPES
   @Test("Test cases of a disabled test are not evaluated")
   func disabledTestCases() async throws {
@@ -478,3 +487,15 @@ private struct BasicRecursiveTrait: SuiteTrait, TestTrait, CustomStringConvertib
     self.description = description
   }
 }
+
+extension PlanTests {
+  // This fixture must not have an explicit `@Suite` attribute to validate suite
+  // synthesis, so it's nested within `PlanTests` to avoid polluting the
+  // top-level namespace. Its children can be `.hidden`, though.
+  private struct OutermostSuite {
+    @Suite(.hidden)
+    struct ChildSuite {
+      @Test func example() {}
+    }
+  }
+}

Tests/TestingTests/RunnerTests.swift

@@ -395,7 +395,7 @@ final class RunnerTests: XCTestCase {
       let runner = await Runner(configuration: configuration)
       let plan = runner.plan
 
-      XCTAssertEqual(plan.steps.count, 0)
+      XCTAssertEqual(plan.steps.count, 1)
     }
   }
 
@@ -501,7 +501,7 @@ final class RunnerTests: XCTestCase {
 
   func testPoundIfTrueTestFunctionRuns() async throws {
     let testStarted = expectation(description: "Test started")
-    testStarted.expectedFulfillmentCount = 4
+    testStarted.expectedFulfillmentCount = 5
     var configuration = Configuration()
     configuration.eventHandler = { event, _ in
       if case .testStarted = event.kind {
@@ -522,7 +522,7 @@ final class RunnerTests: XCTestCase {
 
   func testPoundIfFalseTestFunctionDoesNotRun() async throws {
     let testStarted = expectation(description: "Test started")
-    testStarted.expectedFulfillmentCount = 2
+    testStarted.expectedFulfillmentCount = 3
     var configuration = Configuration()
     configuration.eventHandler = { event, _ in
       if case .testStarted = event.kind {
@@ -545,7 +545,7 @@ final class RunnerTests: XCTestCase {
 
   func testPoundIfFalseElseTestFunctionRuns() async throws {
     let testStarted = expectation(description: "Test started")
-    testStarted.expectedFulfillmentCount = 4
+    testStarted.expectedFulfillmentCount = 5
     var configuration = Configuration()
     configuration.eventHandler = { event, _ in
       if case .testStarted = event.kind {
@@ -568,7 +568,7 @@ final class RunnerTests: XCTestCase {
 
   func testPoundIfFalseElseIfTestFunctionRuns() async throws {
     let testStarted = expectation(description: "Test started")
-    testStarted.expectedFulfillmentCount = 4
+    testStarted.expectedFulfillmentCount = 5
     var configuration = Configuration()
     configuration.eventHandler = { event, _ in
       if case .testStarted = event.kind {
@@ -606,9 +606,9 @@ final class RunnerTests: XCTestCase {
   func testNoasyncTestsAreCallable() async throws {
     let testStarted = expectation(description: "Test started")
 #if !SWT_NO_GLOBAL_ACTORS
-    testStarted.expectedFulfillmentCount = 6
+    testStarted.expectedFulfillmentCount = 7
 #else
-    testStarted.expectedFulfillmentCount = 5
+    testStarted.expectedFulfillmentCount = 6
 #endif
     var configuration = Configuration()
     configuration.eventHandler = { event, _ in
@@ -681,10 +681,10 @@ final class RunnerTests: XCTestCase {
     let testStarted = expectation(description: "Test started")
     let testSkipped = expectation(description: "Test skipped")
 #if SWT_TARGET_OS_APPLE
-    testStarted.expectedFulfillmentCount = 4
+    testStarted.expectedFulfillmentCount = 5
     testSkipped.expectedFulfillmentCount = 8
 #else
-    testStarted.expectedFulfillmentCount = 2
+    testStarted.expectedFulfillmentCount = 3
     testSkipped.expectedFulfillmentCount = 2
 #endif
     var configuration = Configuration()
@@ -782,7 +782,7 @@ final class RunnerTests: XCTestCase {
   func testAvailableWithSwiftVersion() async throws {
     let testStarted = expectation(description: "Test started")
     let testSkipped = expectation(description: "Test skipped")
-    testStarted.expectedFulfillmentCount = 3
+    testStarted.expectedFulfillmentCount = 4
     testSkipped.expectedFulfillmentCount = 2
     var configuration = Configuration()
     configuration.eventHandler = { event, _ in
@@ -808,7 +808,7 @@ final class RunnerTests: XCTestCase {
     }
 
     let testStarted = expectation(description: "Test started")
-    testStarted.expectedFulfillmentCount = 2
+    testStarted.expectedFulfillmentCount = 3
     var configuration = Configuration()
     configuration.eventHandler = { event, _ in
       if case .testStarted = event.kind {
@@ -919,9 +919,9 @@ final class RunnerTests: XCTestCase {
     let testStarted = expectation(description: "Test started")
     let testSkipped = expectation(description: "Test skipped")
 #if SWT_TARGET_OS_APPLE
-    testStarted.expectedFulfillmentCount = 4
+    testStarted.expectedFulfillmentCount = 5
 #else
-    testStarted.expectedFulfillmentCount = 3
+    testStarted.expectedFulfillmentCount = 4
 #endif
     testSkipped.isInverted = true
     var configuration = Configuration()