small perfromance fixes

motivation: better performance

changes:
* cache manifest dependencies and target computations
* change several functions that return static data to computed properties

Author: tomerd

Sources/Basics/FileSystem/AbsolutePath.swift

@@ -268,7 +268,7 @@ extension AbsolutePath {
     }
 
     /// Returns the basename dropping any possible  extension.
-    public func basenameWithoutAnyExtension() -> String {
+    public var basenameWithoutAnyExtension: String {
         var basename = self.basename
         if let index = basename.firstIndex(of: ".") {
             basename.removeSubrange(index ..< basename.endIndex)
@@ -320,7 +320,7 @@ extension AbsolutePath {
 }
 
 extension AbsolutePath {
-    public func escapedPathString() -> String {
+    public var escapedPathString: String {
         self.pathString.replacingOccurrences(of: "\\", with: "\\\\")
     }
 }

Sources/Build/BuildDescription/ProductBuildDescription.swift

@@ -295,7 +295,7 @@ public final class ProductBuildDescription: SPMBuildCore.ProductBuildDescription
         args += try self.buildParameters.targetTripleArgs(for: self.product.targets[0])
 
         // Add arguments from declared build settings.
-        args += self.buildSettingsFlags()
+        args += self.buildSettingsFlags
 
         // Add AST paths to make the product debuggable. This array is only populated when we're
         // building for Darwin in debug configuration.
@@ -325,19 +325,19 @@ public final class ProductBuildDescription: SPMBuildCore.ProductBuildDescription
     }
 
     /// Returns the build flags from the declared build settings.
-    private func buildSettingsFlags() -> [String] {
+    private var buildSettingsFlags: [String] {
         var flags: [String] = []
 
         // Linked libraries.
-        let libraries = OrderedSet(staticTargets.reduce([]) {
-            $0 + buildParameters.createScope(for: $1).evaluate(.LINK_LIBRARIES)
+        let libraries = OrderedSet(self.staticTargets.reduce([]) {
+            $0 + self.buildParameters.createScope(for: $1).evaluate(.LINK_LIBRARIES)
         })
         flags += libraries.map { "-l" + $0 }
 
         // Linked frameworks.
         if self.buildParameters.targetTriple.supportsFrameworks {
-            let frameworks = OrderedSet(staticTargets.reduce([]) {
-                $0 + buildParameters.createScope(for: $1).evaluate(.LINK_FRAMEWORKS)
+            let frameworks = OrderedSet(self.staticTargets.reduce([]) {
+                $0 + self.buildParameters.createScope(for: $1).evaluate(.LINK_FRAMEWORKS)
             })
             flags += frameworks.flatMap { ["-framework", $0] }
         }

Sources/Build/BuildOperation.swift

@@ -669,7 +669,7 @@ public final class BuildOperation: PackageStructureDelegate, SPMBuildCore.BuildS
 
     public func packageStructureChanged() -> Bool {
         do {
-            _ = try plan()
+            _ = try self.plan()
         }
         catch Diagnostics.fatalError {
             return false

Sources/PackageFingerprint/FilePackageFingerprintStorage.swift

@@ -165,7 +165,7 @@ public struct FilePackageFingerprintStorage: PackageFingerprintStorage {
     }
 
     private func loadFromDisk(reference: FingerprintReference) throws -> PackageFingerprints {
-        let path = try self.directoryPath.appending(component: reference.fingerprintsFilename())
+        let path = try self.directoryPath.appending(component: reference.fingerprintsFilename)
 
         guard self.fileSystem.exists(path) else {
             return .init()
@@ -185,7 +185,7 @@ public struct FilePackageFingerprintStorage: PackageFingerprintStorage {
         }
 
         let buffer = try StorageModel.encode(packageFingerprints: fingerprints, encoder: self.encoder)
-        let path = try self.directoryPath.appending(component: reference.fingerprintsFilename())
+        let path = try self.directoryPath.appending(component: reference.fingerprintsFilename)
         try self.fileSystem.writeFileContents(path, data: buffer)
     }
 
@@ -382,25 +382,27 @@ extension Fingerprint.ContentType {
 }
 
 protocol FingerprintReference {
-    func fingerprintsFilename() throws -> String
+    var fingerprintsFilename: String { get throws }
 }
 
 extension PackageIdentity: FingerprintReference {
-    func fingerprintsFilename() -> String {
+    var fingerprintsFilename: String {
         "\(self.description).json"
     }
 }
 
 extension PackageReference: FingerprintReference {
-    func fingerprintsFilename() throws -> String {
-        guard case .remoteSourceControl(let sourceControlURL) = self.kind else {
-            throw StringError("Package kind [\(self.kind)] does not support fingerprints")
+    var fingerprintsFilename: String {
+        get throws {
+            guard case .remoteSourceControl(let sourceControlURL) = self.kind else {
+                throw StringError("Package kind [\(self.kind)] does not support fingerprints")
+            }
+            
+            let canonicalLocation = CanonicalPackageLocation(sourceControlURL.absoluteString)
+            // Cannot use hashValue because it is not consistent across executions
+            let locationHash = canonicalLocation.description.sha256Checksum.prefix(8)
+            return "\(self.identity.description)-\(locationHash).json"
         }
-
-        let canonicalLocation = CanonicalPackageLocation(sourceControlURL.absoluteString)
-        // Cannot use hashValue because it is not consistent across executions
-        let locationHash = canonicalLocation.description.sha256Checksum.prefix(8)
-        return "\(self.identity.description)-\(locationHash).json"
     }
 }
 

Sources/PackageGraph/GraphLoadingNode.swift

@@ -41,8 +41,8 @@ public struct GraphLoadingNode: Equatable, Hashable {
     }
 
     /// Returns the dependencies required by this node.
-    internal func requiredDependencies() -> [PackageDependency] {
-        return manifest.dependenciesRequired(for: productFilter)
+    internal var requiredDependencies: [PackageDependency] {
+        return self.manifest.dependenciesRequired(for: self.productFilter)
     }
 
     public func hash(into hasher: inout Hasher) {

Sources/PackageGraph/ModuleAliasTracker.swift

@@ -84,7 +84,7 @@ class ModuleAliasTracker {
     func trackTargetsPerProduct(product: Product,
                                 package: PackageIdentity) {
         let targetDeps = product.targets.map{$0.dependencies}.flatMap{$0}
-        var allTargetDeps = product.targets.map{$0.recursiveDependentTargets().map{$0.dependencies}}.flatMap{$0}.flatMap{$0}
+        var allTargetDeps = product.targets.map{$0.recursiveDependentTargets.map{$0.dependencies}}.flatMap{$0}.flatMap{$0}
         allTargetDeps.append(contentsOf: targetDeps)
         for dep in allTargetDeps {
             if case let .product(depRef, _) = dep {
@@ -158,7 +158,7 @@ class ModuleAliasTracker {
         }
 
         if let curDirectTargets = productToDirectTargets[productID] {
-            var relevantTargets = curDirectTargets.map{$0.recursiveDependentTargets()}.flatMap{$0}
+            var relevantTargets = curDirectTargets.map{$0.recursiveDependentTargets}.flatMap{$0}
             relevantTargets.append(contentsOf: curDirectTargets)
 
             for relTarget in relevantTargets {
@@ -198,7 +198,7 @@ class ModuleAliasTracker {
         }
 
         if let curDirectTargets = productToDirectTargets[productID] {
-            let depTargets = curDirectTargets.map{$0.recursiveDependentTargets()}.flatMap{$0}
+            let depTargets = curDirectTargets.map{$0.recursiveDependentTargets}.flatMap{$0}
             let depTargetAliases = toDictionary(depTargets.compactMap{$0.moduleAliases})
             let depChildTargets = dependencyProductTargets(of: depTargets)
             let depChildAliases = toDictionary(depChildTargets.compactMap{$0.moduleAliases})
@@ -255,7 +255,7 @@ class ModuleAliasTracker {
                 let unAliased = productTargets.contains{$0.moduleAliases == nil}
                 if unAliased {
                     for target in productTargets {
-                        let depAliases = target.recursiveDependentTargets().compactMap{$0.moduleAliases}.flatMap{$0}
+                        let depAliases = target.recursiveDependentTargets.compactMap{$0.moduleAliases}.flatMap{$0}
                         for (key, alias) in depAliases {
                             target.addModuleAlias(for: key, as: alias)
                         }
@@ -412,17 +412,17 @@ class ModuleAliasModel {
 
 extension Target {
     func dependsOn(productID: String) -> Bool {
-        return dependencies.contains { dep in
+        return self.dependencies.contains { dep in
             if case let .product(prodRef, _) = dep {
                 return prodRef.identity == productID
             }
             return false
         }
     }
 
-    func recursiveDependentTargets() -> [Target] {
+    var recursiveDependentTargets: [Target] {
         var list = [Target]()
-        var nextDeps = dependencies
+        var nextDeps = self.dependencies
         while !nextDeps.isEmpty {
             let nextTargets = nextDeps.compactMap{$0.target}
             list.append(contentsOf: nextTargets)

Sources/PackageGraph/PackageGraph+Loading.swift

@@ -46,7 +46,7 @@ extension PackageGraph {
             manifestMap[$0.key] = ($0.value, fileSystem)
         }
         let successors: (GraphLoadingNode) -> [GraphLoadingNode] = { node in
-            node.requiredDependencies().compactMap{ dependency in
+            node.requiredDependencies.compactMap{ dependency in
                 return manifestMap[dependency.identity].map { (manifest, fileSystem) in
                     GraphLoadingNode(identity: dependency.identity, manifest: manifest, productFilter: dependency.productFilter, fileSystem: fileSystem)
                 }
@@ -272,7 +272,7 @@ private func createResolvedPackages(
 
         // Establish the manifest-declared package dependencies.
         package.manifest.dependenciesRequired(for: packageBuilder.productFilter).forEach { dependency in
-            let dependencyPackageRef = dependency.createPackageRef()
+            let dependencyPackageRef = dependency.packageRef
 
             // Otherwise, look it up by its identity.
             if let resolvedPackage = packagesByIdentity[dependency.identity] {

Sources/PackageGraph/PackageGraphRoot.swift

@@ -88,7 +88,7 @@ public struct PackageGraphRoot {
 
         let depend = try dependencies.map{
             PackageContainerConstraint(
-                package: $0.createPackageRef(),
+                package: $0.packageRef,
                 requirement: try $0.toConstraintRequirement(),
                 products: $0.productFilter
             )

Sources/PackageGraph/PackageModel+Extensions.swift

@@ -14,7 +14,7 @@ import PackageModel
 
 extension PackageDependency {
     /// Create the package reference object for the dependency.
-    public func createPackageRef() -> PackageReference {
+    public var packageRef: PackageReference {
         let packageKind: PackageReference.Kind
         switch self {
         case .fileSystem(let settings):
@@ -38,7 +38,7 @@ extension Manifest {
     public func dependencyConstraints(productFilter: ProductFilter) throws -> [PackageContainerConstraint] {
         return try self.dependenciesRequired(for: productFilter).map({
             return PackageContainerConstraint(
-                package: $0.createPackageRef(),
+                package: $0.packageRef,
                 requirement: try $0.toConstraintRequirement(),
                 products: $0.productFilter)
         })