Implement __SKIP_BUILD setting to prune test runners from builds for apple platforms

Author: owenv

Sources/SWBCore/Settings/BuiltinMacros.swift

@@ -1300,6 +1300,8 @@ public final class BuiltinMacros {
     // Info.plist Keys - Sticker Packs
     public static let INFOPLIST_KEY_NSStickerSharingLevel = BuiltinMacros.declareEnumMacro("INFOPLIST_KEY_NSStickerSharingLevel") as EnumMacroDeclaration<StickerSharingLevel>
 
+    public static let __SKIP_BUILD = BuiltinMacros.declareBooleanMacro("__SKIP_BUILD")
+
     // MARK: Built-in Macro Initialization
 
     private static var initialized = false
@@ -2391,7 +2393,8 @@ public final class BuiltinMacros {
         ENABLE_XOJIT_PREVIEWS,
         BUILD_ACTIVE_RESOURCES_ONLY,
         ENABLE_ONLY_ACTIVE_RESOURCES,
-        ENABLE_PLAYGROUND_RESULTS
+        ENABLE_PLAYGROUND_RESULTS,
+        __SKIP_BUILD
     ]
 
     /// Force initialization of entitlements macros.

Sources/SWBCore/TargetDependencyResolver.swift

@@ -553,18 +553,24 @@ fileprivate extension TargetDependencyResolver {
             delegate.emit(.init(behavior: .error, location: .unknown, data: .init("The 'Skip Dependencies' option is deprecated and can no longer be used.")))
         }
 
-        // Apply the requested dependency scope to the graph.
+        // Prune targets from the graph as needed.
+        var keptTargets: OrderedSet<ConfiguredTarget>
+        var removedTargets: OrderedSet<ConfiguredTarget>
+
+        // First, determine targets to be removed based on the dependency scope.
         switch buildRequest.dependencyScope {
         case .workspace:
             // If dependencies are scoped to the workspace, no pruning is required.
+            keptTargets = allTargets
+            removedTargets = []
             break
         case .buildRequest:
             if buildRequest.skipDependencies {
                 delegate.emit(.init(behavior: .error, location: .unknown, data: .init("The 'Skip Dependencies' option is deprecated and cannot be combined with dependency scopes.")))
             }
             // First, partition the targets into those we're keeping, and those we're removing.
-            var keptTargets: OrderedSet<ConfiguredTarget> = []
-            var removedTargets: OrderedSet<ConfiguredTarget> = []
+            keptTargets = []
+            removedTargets = []
             let requestedTargetGUIDs = Set(buildRequest.buildTargets.map(\.target.guid))
             var extraRequestedTargetGUIDs: Set<String> = []
             var potentialExtraRequestedPackageTargetGUIDs: Set<String> = []
@@ -594,8 +600,18 @@ fileprivate extension TargetDependencyResolver {
                     removedTargets.append(configuredTarget)
                 }
             }
+        }
+
+        // Then, remove targets based on the value of the __SKIP_BUILD setting.
+        let targetsToRemoveBasedOnSettings = keptTargets.filter { configuredTarget in
+            let settings = buildRequestContext.getCachedSettings(configuredTarget.parameters, target: configuredTarget.target)
+            return settings.globalScope.evaluate(BuiltinMacros.__SKIP_BUILD)
+        }
+        keptTargets.subtract(targetsToRemoveBasedOnSettings)
+        removedTargets.append(contentsOf: targetsToRemoveBasedOnSettings)
 
-            // For each removed target, identify all kept targets reachable by traversing only edges which originate at a removed target.
+        // For each removed target, identify all kept targets reachable by traversing only edges which originate at a removed target.
+        if !removedTargets.isEmpty {
             var reachableKeptTargetsByRemovedTarget: [ConfiguredTarget: OrderedSet<ConfiguredTarget>] = [:]
             do {
                 func visit(_ configuredTarget: ConfiguredTarget) {

Tests/SWBCoreTests/DependencyScopingTests.swift

@@ -100,6 +100,77 @@ import Foundation
         }
     }
 
+    @Test(.requireSDKs(.macOS))
+    func skipBuildSetting() async throws {
+        let core = try await getCore()
+
+        let workspace = try TestWorkspace(
+            "Workspace",
+            projects: [
+                TestProject(
+                    "P1",
+                    groupTree: TestGroup(
+                        "G1",
+                        children: [
+                            TestFile("S1.c"),
+                        ]
+                    ),
+                    buildConfigurations: [
+                        TestBuildConfiguration("Debug", buildSettings: [:]),
+                    ],
+                    targets: [
+                        TestStandardTarget(
+                            "T1",
+                            type: .framework,
+                            buildConfigurations: [
+                                TestBuildConfiguration("Debug", buildSettings: ["PRODUCT_NAME": "$(TARGET_NAME)", "__SKIP_BUILD": "YES"]),
+                            ],
+                            buildPhases: [
+                                TestSourcesBuildPhase(["S1.c"])
+                            ],
+                            dependencies: ["T2"]
+                        ),
+                        TestStandardTarget(
+                            "T2",
+                            type: .framework,
+                            buildConfigurations: [
+                                TestBuildConfiguration("Debug", buildSettings: ["PRODUCT_NAME": "$(TARGET_NAME)"]),
+                            ],
+                            buildPhases: [
+                                TestSourcesBuildPhase(["S1.c"])
+                            ],
+                            dependencies: ["T3"]
+                        ),
+                        TestStandardTarget(
+                            "T3",
+                            type: .framework,
+                            buildConfigurations: [
+                                TestBuildConfiguration("Debug", buildSettings: ["PRODUCT_NAME": "$(TARGET_NAME)"]),
+                            ],
+                            buildPhases: [
+                                TestSourcesBuildPhase(["S1.c"])
+                            ]
+                        )
+                    ]
+                ),
+            ]
+        ).load(core)
+        let workspaceContext = WorkspaceContext(core: core, workspace: workspace, processExecutionCache: .sharedForTesting)
+
+        // Configure the targets and create a BuildRequest.
+        let buildParameters = BuildParameters(configuration: "Debug")
+        let t1 = BuildRequest.BuildTargetInfo(parameters: buildParameters, target: workspace.target(named: "T1")!)
+        let t2 = BuildRequest.BuildTargetInfo(parameters: buildParameters, target: workspace.target(named: "T2")!)
+        do {
+            let buildRequest = BuildRequest(parameters: buildParameters, buildTargets: [t1], dependencyScope: .workspace, continueBuildingAfterErrors: true, useParallelTargets: false, useImplicitDependencies: true, useDryRun: false)
+            let buildRequestContext = BuildRequestContext(workspaceContext: workspaceContext)
+            let delegate = EmptyTargetDependencyResolverDelegate(workspace: workspaceContext.workspace)
+            let buildGraph = await TargetGraphFactory(workspaceContext: workspaceContext, buildRequest: buildRequest, buildRequestContext: buildRequestContext, delegate: delegate).graph(type: .dependency)
+            #expect(buildGraph.allTargets.map({ $0.target.name }) == ["T3", "T2"])
+            delegate.checkNoDiagnostics()
+        }
+    }
+
     @Test(.requireSDKs(.macOS))
     func buildRequestScopeRemovingInteriorTarget() async throws {
         let core = try await getCore()