Skip building static frameworks by checking Mach-O type

Source/CarthageKit/Xcode.swift

@@ -468,6 +468,52 @@ public enum ProductType: String {
 	}
 }
 
+/// Describes the type of Mach-O files.
+/// See https://developer.apple.com/library/mac/documentation/DeveloperTools/Reference/XcodeBuildSettingRef/1-Build_Setting_Reference/build_setting_ref.html#//apple_ref/doc/uid/TP40003931-CH3-SW73.
+public enum MachOType: String {
+	/// Executable binary.
+	case Executable = "mh_executable"
+
+	/// Bundle binary.
+	case Bundle = "mh_bundle"
+
+	/// Relocatable object file.
+	case Object = "mh_object"
+
+	/// Dynamic library binary.
+	case Dylib = "mh_dylib"
+
+	/// Static library binary.
+	case Staticlib = "staticlib"
+
+	/// Attempts to parse a Mach-O type from a string returned from `xcodebuild`.
+	public static func fromString(string: String) -> Result<MachOType, CarthageError> {
+		return Result(self.init(rawValue: string), failWith: .ParseError(description: "unexpected Mach-O type \"\(string)\""))
+	}
+}
+
+/// Describes the type of frameworks.
+private enum FrameworkType {
+	/// A dynamic framework.
+	case Dynamic
+
+	/// A static framework.
+	case Static
+
+	init?(productType: ProductType, machOType: MachOType) {
+		switch (productType, machOType) {
+		case (.Framework, .Dylib):
+			self = .Dynamic
+
+		case (.Framework, .Staticlib):
+			self = .Static
+
+		case _:
+			return nil
+		}
+	}
+}
+
 /// A map of build settings and their values, as generated by Xcode.
 public struct BuildSettings {
 	/// The target to which these settings apply.
@@ -586,6 +632,16 @@ public struct BuildSettings {
 		}
 	}
 
+	/// Attempts to determine the MachOType specified in these build settings.
+	public var machOType: Result<MachOType, CarthageError> {
+		return self["MACH_O_TYPE"].flatMap(MachOType.fromString)
+	}
+
+	/// Attempts to determine the FrameworkType identified by these build settings.
+	private var frameworkType: Result<FrameworkType?, CarthageError> {
+		return (productType &&& machOType).map(FrameworkType.init)
+	}
+
 	/// Attempts to determine the URL to the built products directory.
 	public var builtProductsDirectoryURL: Result<NSURL, CarthageError> {
 		return self["BUILT_PRODUCTS_DIR"].map { productsDir in
@@ -728,31 +784,31 @@ private func mergeModuleIntoModule(sourceModuleDirectoryURL: NSURL, _ destinatio
 		}
 }
 
-/// Determines whether the specified product type should be built automatically.
-private func shouldBuildProductType(productType: ProductType) -> Bool {
-	return productType == .Framework
+/// Determines whether the specified framework type should be built automatically.
+private func shouldBuildFrameworkType(frameworkType: FrameworkType?) -> Bool {
+	return frameworkType == .Dynamic
 }
 
 /// Determines whether the given scheme should be built automatically.
 private func shouldBuildScheme(buildArguments: BuildArguments, _ forPlatforms: Set<Platform>) -> SignalProducer<Bool, CarthageError> {
 	precondition(buildArguments.scheme != nil)
 
 	return BuildSettings.loadWithArguments(buildArguments)
-		.flatMap(.Concat) { settings -> SignalProducer<ProductType, CarthageError> in
-			let productType = SignalProducer(result: settings.productType)
+		.flatMap(.Concat) { settings -> SignalProducer<FrameworkType?, CarthageError> in
+			let frameworkType = SignalProducer(result: settings.frameworkType)
 
 			if forPlatforms.isEmpty {
-				return productType
+				return frameworkType
 					.flatMapError { _ in .empty }
 			} else {
 				return settings.buildSDKs
 					.filter { forPlatforms.contains($0.platform) }
-					.flatMap(.Merge) { _ in productType }
+					.flatMap(.Merge) { _ in frameworkType }
 					.flatMapError { _ in .empty }
 			}
 		}
-		.filter(shouldBuildProductType)
-		// If we find any framework target, we should indeed build this scheme.
+		.filter(shouldBuildFrameworkType)
+		// If we find any dynamic framework target, we should indeed build this scheme.
 		.map { _ in true }
 		// Otherwise, nope.
 		.concat(SignalProducer(value: false))
@@ -908,9 +964,9 @@ public func buildScheme(scheme: String, withConfiguration configuration: String,
 
 				return BuildSettings.loadWithArguments(argsForLoading)
 					.filter { settings in
-						// Only copy build products for the product types we care about.
-						if let productType = settings.productType.value {
-							return shouldBuildProductType(productType)
+						// Only copy build products for the framework type we care about.
+						if let frameworkType = settings.frameworkType.value {
+							return shouldBuildFrameworkType(frameworkType)
 						} else {
 							return false
 						}