Conditional target dependencies manifest api

Sources/Build/BuildPlan.swift

@@ -88,7 +88,10 @@ extension BuildParameters {
 
     /// Returns the scoped view of build settings for a given target.
     fileprivate func createScope(for target: ResolvedTarget) -> BuildSettings.Scope {
-        return BuildSettings.Scope(target.underlyingTarget.buildSettings, boundCondition: (currentPlatform, configuration))
+        return BuildSettings.Scope(
+            target.underlyingTarget.buildSettings,
+            environment: BuildEnvironment(platform: currentPlatform, configuration: configuration)
+        )
     }
 }
 

Sources/PackageDescription4/BuildSettings.swift

@@ -45,7 +45,7 @@ public struct BuildConfiguration: Encodable {
 ///             .define("ENABLE_SOMETHING", .when(configuration: .release)),
 ///         ],
 ///         linkerSettings: [
-///             .linkLibrary("openssl", .when(platforms: [.linux])),
+///             .linkedLibrary("openssl", .when(platforms: [.linux])),
 ///         ]
 ///     ),
 public struct BuildSettingCondition: Encodable {
@@ -228,7 +228,7 @@ public struct SwiftSetting: Encodable {
     /// Use compilation conditions to only compile statements if a certain condition is true.
     /// For example, the Swift compiler will only compile the
     /// statements inside the `#if` block when `ENABLE_SOMETHING` is defined:
-    ///     
+    ///
     ///     #if ENABLE_SOMETHING
     ///        ...
     ///     #endif

Sources/PackageDescription4/Package.swift

@@ -452,6 +452,7 @@ extension Target.Dependency: Encodable {
         case type
         case name
         case package
+        case condition
     }
 
     private enum Kind: String, Codable {
@@ -477,16 +478,19 @@ extension Target.Dependency: Encodable {
         }
       #else
         switch self {
-        case ._targetItem(let name):
+        case ._targetItem(let name, let condition):
             try container.encode(Kind.target, forKey: .type)
             try container.encode(name, forKey: .name)
-        case ._productItem(let name, let package):
+            try container.encode(condition, forKey: .condition)
+        case ._productItem(let name, let package, let condition):
             try container.encode(Kind.product, forKey: .type)
             try container.encode(name, forKey: .name)
             try container.encode(package, forKey: .package)
-        case ._byNameItem(let name):
+            try container.encode(condition, forKey: .condition)
+        case ._byNameItem(let name, let condition):
             try container.encode(Kind.byName, forKey: .type)
             try container.encode(name, forKey: .name)
+            try container.encode(condition, forKey: .condition)
         }
       #endif
     }

Sources/PackageDescription4/Target.swift

@@ -33,9 +33,9 @@ public final class Target {
         case productItem(name: String, package: String?)
         case byNameItem(name: String)
       #else
-        case _targetItem(name: String)
-        case _productItem(name: String, package: String?)
-        case _byNameItem(name: String)
+        case _targetItem(name: String, condition: BuildSettingCondition?)
+        case _productItem(name: String, package: String?, condition: BuildSettingCondition?)
+        case _byNameItem(name: String, condition: BuildSettingCondition?)
       #endif
     }
 
@@ -490,11 +490,12 @@ extension Target.Dependency {
     ///
     /// - parameters:
     ///   - name: The name of the target.
+    @available(_PackageDescription, obsoleted: 5.2)
     public static func target(name: String) -> Target.Dependency {
       #if PACKAGE_DESCRIPTION_4
         return .targetItem(name: name)
       #else
-        return ._targetItem(name: name)
+        return ._targetItem(name: name, condition: nil)
       #endif
     }
 
@@ -508,36 +509,61 @@ extension Target.Dependency {
       #if PACKAGE_DESCRIPTION_4
         return .productItem(name: name, package: package)
       #else
-        return ._productItem(name: name, package: package)
+        return ._productItem(name: name, package: package, condition: nil)
       #endif
     }
 
+    /// Creates a by-name dependency that resolves to either a target or a product but
+    /// after the package graph has been loaded.
+    ///
+    /// - parameters:
+    ///   - name: The name of the dependency, either a target or a product.
+    @available(_PackageDescription, obsoleted: 5.2)
+    public static func byName(name: String) -> Target.Dependency {
+      #if PACKAGE_DESCRIPTION_4
+        return .byNameItem(name: name)
+      #else
+        return ._byNameItem(name: name, condition: nil)
+      #endif
+    }
+
+  #if !PACKAGE_DESCRIPTION_4
+    /// Creates a dependency on a target in the same package.
+    ///
+    /// - parameters:
+    ///   - name: The name of the target.
+    ///   - condition: The condition under which the dependency is exercised.
+    @available(_PackageDescription, introduced: 5.2)
+    public static func target(name: String, condition: BuildSettingCondition? = nil) -> Target.Dependency {
+        return ._targetItem(name: name, condition: condition)
+    }
+
     /// Creates a dependency on a product from a package dependency.
     ///
     /// - parameters:
     ///   - name: The name of the product.
     ///   - package: The name of the package.
+    ///   - condition: The condition under which the dependency is exercised.
     @available(_PackageDescription, introduced: 5.2)
-    public static func product(name: String, package: String) -> Target.Dependency {
-      #if PACKAGE_DESCRIPTION_4
-        return .productItem(name: name, package: package)
-      #else
-        return ._productItem(name: name, package: package)
-      #endif
+    public static func product(
+        name: String,
+        package: String,
+        condition: BuildSettingCondition? = nil
+    ) -> Target.Dependency {
+        return ._productItem(name: name, package: package, condition: condition)
     }
 
     /// Creates a by-name dependency that resolves to either a target or a product but
     /// after the package graph has been loaded.
     ///
     /// - parameters:
     ///   - name: The name of the dependency, either a target or a product.
-    public static func byName(name: String) -> Target.Dependency {
-      #if PACKAGE_DESCRIPTION_4
-        return .byNameItem(name: name)
-      #else
-        return ._byNameItem(name: name)
-      #endif
+    ///   - condition: The condition under which the dependency is exercised.
+    @available(_PackageDescription, introduced: 5.2)
+    public static func byName(name: String, condition: BuildSettingCondition? = nil) -> Target.Dependency {
+        return ._byNameItem(name: name, condition: condition)
     }
+  #endif
 }
 
 // MARK: ExpressibleByStringLiteral
@@ -552,7 +578,7 @@ extension Target.Dependency: ExpressibleByStringLiteral {
       #if PACKAGE_DESCRIPTION_4
         self = .byNameItem(name: value)
       #else
-        self = ._byNameItem(name: value)
+        self = ._byNameItem(name: value, condition: nil)
       #endif
     }
 }

Sources/PackageLoading/ManifestLoader.swift

@@ -275,14 +275,14 @@ public final class ManifestLoader: ManifestLoaderProtocol {
                 for targetDependency in target.dependencies {
                     // If this is a target dependency (or byName that references a target), we don't need to check.
                     if case .target = targetDependency { continue }
-                    if case .byName(let name) = targetDependency, targetNames.contains(name) { continue }
+                    if case .byName(let name, _) = targetDependency, targetNames.contains(name) { continue }
 
                     // If we can't find the package dependency it references, the manifest is invalid.
                     if manifest.packageDependency(referencedBy: targetDependency) == nil {
                         let packageName: String
                         switch targetDependency {
-                        case .product(_, package: let name?),
-                             .byName(let name):
+                        case .product(_, package: let name?, _),
+                             .byName(let name, _):
                             packageName = name
                         default:
                             fatalError("Invalid case: this shouldn't be a target, or a product with no name")

Sources/PackageLoading/PackageBuilder.swift

@@ -526,14 +526,14 @@ public final class PackageBuilder {
             guard let target = targetMap[$0.name] else { return [] }
             return target.dependencies.compactMap({
                 switch $0 {
-                case .target(let name):
+                case .target(let name, _):
                     // Since we already checked above that all referenced targets
                     // has to present, we always expect this target to be present in
                     // potentialModules dictionary.
                     return potentialModuleMap[name]!
                 case .product:
                     return nil
-                case .byName(let name):
+                case .byName(let name, _):
                     // By name dependency may or may not be a target dependency.
                     return potentialModuleMap[name]
                 }
@@ -559,12 +559,12 @@ public final class PackageBuilder {
             let deps: [Target] = targetMap[potentialModule.name].map({
                 $0.dependencies.compactMap({
                     switch $0 {
-                    case .target(let name):
+                    case .target(let name, _):
                         // We don't create an object for targets which have no sources.
                         if emptyModules.contains(name) { return nil }
                         return targets[name]!
 
-                    case .byName(let name):
+                    case .byName(let name, _):
                         // We don't create an object for targets which have no sources.
                         if emptyModules.contains(name) { return nil }
                         return targets[name]
@@ -583,10 +583,10 @@ public final class PackageBuilder {
                 switch $0 {
                 case .target:
                     return nil
-                case .byName(let name):
+                case .byName(let name, _):
                     // If this dependency was not found locally, it is a product dependency.
                     return potentialModuleMap[name] == nil ? (name, nil) : nil
-                case .product(let name, let package):
+                case .product(let name, let package, _):
                     return (name, package)
                 }
             }) ?? []
@@ -788,13 +788,12 @@ public final class PackageBuilder {
             assignment.value = setting.value
 
             if let config = setting.condition?.config.map({ BuildConfiguration(rawValue: $0)! }) {
-                let condition = BuildSettings.ConfigurationCondition(config)
+                let condition = ConfigurationCondition(configuration: config)
                 assignment.conditions.append(condition)
             }
 
             if let platforms = setting.condition?.platformNames.map({ platformRegistry.platformByName[$0]! }), !platforms.isEmpty {
-                var condition = BuildSettings.PlatformsCondition()
-                condition.platforms = platforms
+                let condition = PlatformsCondition(platforms: platforms)
                 assignment.conditions.append(condition)
             }
 
@@ -1116,7 +1115,7 @@ private extension Manifest {
         let names = targets.flatMap({ target in
             [target.name] + target.dependencies.compactMap({
                 switch $0 {
-                case .target(let name):
+                case .target(let name, _):
                     return name
                 case .byName, .product:
                     return nil

Sources/PackageLoading/PackageDescription4Loader.swift

@@ -150,11 +150,7 @@ extension ManifestBuilder {
     func parseBuildSetting(_ json: JSON, tool: TargetBuildSettingDescription.Tool) throws -> TargetBuildSettingDescription.Setting {
         let json = try json.getJSON("data")
         let name = try TargetBuildSettingDescription.SettingName(rawValue: json.get("name"))!
-
-        var condition: TargetBuildSettingDescription.Condition?
-        if let conditionJSON = try? json.getJSON("condition") {
-            condition = try parseCondition(conditionJSON)
-        }
+        let condition = try (try? json.getJSON("condition")).flatMap(ManifestConditionDescription.init(v4:))
 
         let value = try json.get([String].self, forKey: "value")
 
@@ -176,14 +172,6 @@ extension ManifestBuilder {
 
     /// Looks for Xcode-style build setting macros "$()".
     private static let invalidValueRegex = try! RegEx(pattern: #"(\$\(.*?\))"#)
-
-    func parseCondition(_ json: JSON) throws -> TargetBuildSettingDescription.Condition {
-        let platformNames: [String]? = try? json.getArray("platforms").map({ try $0.get("name") })
-        return .init(
-            platformNames: platformNames ?? [],
-            config: try? json.get("config").get("config")
-        )
-    }
 }
 
 extension SystemPackageProviderDescription {
@@ -332,20 +320,32 @@ extension TargetDescription.TargetType {
 extension TargetDescription.Dependency {
     fileprivate init(v4 json: JSON) throws {
         let type = try json.get(String.self, forKey: "type")
+        let condition = try (try? json.getJSON("condition")).flatMap(ManifestConditionDescription.init(v4:))
 
         switch type {
         case "target":
-            self = try .target(name: json.get("name"))
+            self = try .target(name: json.get("name"), condition: condition)
 
         case "product":
             let name = try json.get(String.self, forKey: "name")
-            self = .product(name: name, package: json.get("package"))
+            self = .product(name: name, package: json.get("package"), condition: condition)
 
         case "byname":
-            self = try .byName(name: json.get("name"))
+            self = try .byName(name: json.get("name"), condition: condition)
 
         default:
             fatalError()
         }
     }
 }
+
+extension ManifestConditionDescription {
+    fileprivate init?(v4 json: JSON) throws {
+        if case .null = json { return nil }
+        let platformNames: [String]? = try? json.getArray("platforms").map({ try $0.get("name") })
+        self.init(
+            platformNames: platformNames ?? [],
+            config: try? json.get("config").get("config")
+        )
+    }
+}