Merge pull request #1 from Shepherd-Dog/feature/handleModuleStability2

 Consider module stability when building frameworks

Source/CarthageKit/Xcode.swift

@@ -134,12 +134,36 @@ internal func isSwiftFramework(_ frameworkURL: URL) -> Bool {
 internal func checkSwiftFrameworkCompatibility(_ frameworkURL: URL, usingToolchain toolchain: String?) -> SignalProducer<URL, SwiftVersionError> {
 	return SignalProducer.combineLatest(swiftVersion(usingToolchain: toolchain), frameworkSwiftVersion(frameworkURL))
 		.attemptMap { localSwiftVersion, frameworkSwiftVersion in
-			return localSwiftVersion == frameworkSwiftVersion
+			return localSwiftVersion == frameworkSwiftVersion || isModuleStableAPI(localSwiftVersion, frameworkSwiftVersion, frameworkURL)
 				? .success(frameworkURL)
 				: .failure(.incompatibleFrameworkSwiftVersions(local: localSwiftVersion, framework: frameworkSwiftVersion))
 		}
 }
 
+/// Determines whether a local swift version and a framework combination are considered module stable
+internal func isModuleStableAPI(_ localSwiftVersion: String,
+								_ frameworkSwiftVersion: String,
+								_ frameworkURL: URL) -> Bool {
+	guard let localSwiftVersionNumber = determineMajorMinorVersion(localSwiftVersion),
+		let frameworkSwiftVersionNumber = determineMajorMinorVersion(frameworkSwiftVersion),
+		let swiftModuleURL = frameworkURL.swiftmoduleURL() else { return false }
+
+	let hasSwiftInterfaceFile = try? FileManager.default.contentsOfDirectory(at: swiftModuleURL,
+																			 includingPropertiesForKeys: nil,
+																			 options: []).first { (url) -> Bool in
+			return url.lastPathComponent.contains("swiftinterface")
+		} != nil
+
+	return localSwiftVersionNumber >= 5.1 && frameworkSwiftVersionNumber >= 5.1 && hasSwiftInterfaceFile == true
+}
+
+/// Attempts to return a `Double` representing the major/minor version components parsed from a given swift version, otherwise returns `nil`.
+private func determineMajorMinorVersion(_ swiftVersion: String) -> Double? {
+	guard let range = swiftVersion.range(of: "^(\\d+)\\.(\\d+)", options: .regularExpression) else { return nil }
+
+	return Double(swiftVersion[range])
+}
+
 /// Emits the framework URL if it is compatible with the build environment and errors if not.
 internal func checkFrameworkCompatibility(_ frameworkURL: URL, usingToolchain toolchain: String?) -> SignalProducer<URL, SwiftVersionError> {
 	if isSwiftFramework(frameworkURL) {

Tests/CarthageKitTests/XcodeSpec.swift

@@ -98,6 +98,33 @@ class XcodeSpec: QuickSpec {
 
 				expect(result?.value) == "4.1-dev (LLVM 0fcc19c0d8, Clang 1696f82ad2, Swift 691139445e)"
 			}
+
+			it("should determine when a module-stable Swift framework is incompatible") {
+				let localSwiftVersion = "5.0 (swiftlang-1001.0.69.5 clang-1001.0.46.3)"
+				let frameworkVersion = "5.1.2 (swiftlang-1100.0.278 clang-1100.0.33.9)"
+				let frameworkURL = Bundle(for: type(of: self)).url(forResource: "ModuleStableBuiltWithSwift5.1.2.framework", withExtension: nil)!
+				let result = isModuleStableAPI(localSwiftVersion, frameworkVersion, frameworkURL)
+
+				expect(result).to(beFalse())
+			}
+
+			it("should determine when a non-module-stable Swift framework is incompatible") {
+				let localSwiftVersion = "5.1 (swiftlang-1100.0.270.13 clang-1100.0.33.7)"
+				let frameworkVersion = "5.1.2 (swiftlang-1100.0.278 clang-1100.0.33.9)"
+				let frameworkURL = Bundle(for: type(of: self)).url(forResource: "NonModuleStableBuiltWithSwift5.1.2.framework", withExtension: nil)!
+				let result = isModuleStableAPI(localSwiftVersion, frameworkVersion, frameworkURL)
+
+				expect(result).to(beFalse())
+			}
+
+			it("should determine when a module-stable Swift framework is compatible") {
+				let localSwiftVersion = "5.1 (swiftlang-1100.0.270.13 clang-1100.0.33.7)"
+				let frameworkVersion = "5.1.2 (swiftlang-1100.0.278 clang-1100.0.33.9)"
+				let frameworkURL = Bundle(for: type(of: self)).url(forResource: "ModuleStableBuiltWithSwift5.1.2.framework", withExtension: nil)!
+				let result = isModuleStableAPI(localSwiftVersion, frameworkVersion, frameworkURL)
+
+				expect(result).to(beTrue())
+			}
 		}
 
 		describe("locateProjectsInDirectory:") {

script/copy-fixtures

@@ -12,7 +12,7 @@ fi
 current=$(cd "$(dirname $0)" && pwd)
 destination="$1"
 
-for fixture in "carthage-fixtures-ReactiveCocoaLayout-master" "CartfileOnly" "CartfilePrivateOnly" "NoCartfile" "SchemeDiscoverySampleForCarthage-0.2" "Swell-0.5.0" "SampleMultipleSubprojects" "SampleGitSubmodule" "DependencyTest" "WorkspaceWithDependency" "DynamicAndStatic" "WorkspaceWithDependency" "FilterBogusFrameworks" "NoSharedSchemesTest" "CleanupTest"
+for fixture in "carthage-fixtures-ReactiveCocoaLayout-master" "CartfileOnly" "CartfilePrivateOnly" "NoCartfile" "SchemeDiscoverySampleForCarthage-0.2" "Swell-0.5.0" "SampleMultipleSubprojects" "SampleGitSubmodule" "DependencyTest" "WorkspaceWithDependency" "DynamicAndStatic" "WorkspaceWithDependency" "FilterBogusFrameworks" "NoSharedSchemesTest" "CleanupTest" "ModuleStableBuiltWithSwift5.1.2" "NonModuleStableBuiltWithSwift5.1.2"
 do
     rm -Rf "$destination/__MACOSX"
     rm -Rf "$destination/$fixture"