Merge pull request #1192 from ddunbar/stable-ids

[Xcodeproj] Assign stable object IDs to critical objects.

Author: ddunbar

Sources/Xcodeproj/XcodeProjectModel.swift

@@ -75,8 +75,8 @@ public struct Xcode {
 
         /// Creates and adds a new target (which does not initially have any
         /// build phases).
-        public func addTarget(productType: Target.ProductType?, name: String) -> Target {
-            let target = Target(productType: productType, name: name)
+        public func addTarget(objectID: String? = nil, productType: Target.ProductType?, name: String) -> Target {
+            let target = Target(objectID: objectID, productType: productType, name: name)
             targets.append(target)
             return target
         }
@@ -119,10 +119,12 @@ public struct Xcode {
 
     /// A reference to a file system entity (a file, folder, etc).
     public class FileReference: Reference {
+        var objectID: String?
         var fileType: String?
 
-        init(path: String, pathBase: RefPathBase = .groupDir, name: String? = nil, fileType: String? = nil) {
+        init(path: String, pathBase: RefPathBase = .groupDir, name: String? = nil, fileType: String? = nil, objectID: String? = nil) {
             super.init(path: path, pathBase: pathBase, name: name)
+            self.objectID = objectID
             self.fileType = fileType
         }
     }
@@ -150,16 +152,18 @@ public struct Xcode {
             path: String,
             pathBase: RefPathBase = .groupDir,
             name: String? = nil,
-            fileType: String? = nil
+            fileType: String? = nil,
+            objectID: String? = nil
         ) -> FileReference {
-            let fref = FileReference(path: path, pathBase: pathBase, name: name, fileType: fileType)
+            let fref = FileReference(path: path, pathBase: pathBase, name: name, fileType: fileType, objectID: objectID)
             subitems.append(fref)
             return fref
         }
     }
 
     /// An Xcode target, representing a single entity to build.
     public class Target {
+        var objectID: String?
         var name: String
         var productName: String
         var productType: ProductType?
@@ -176,7 +180,8 @@ public struct Xcode {
             case unitTest = "com.apple.product-type.bundle.unit-test"
             var asString: String { return rawValue }
         }
-        init(productType: ProductType?, name: String) {
+        init(objectID: String?, productType: ProductType?, name: String) {
+            self.objectID = objectID
             self.name = name
             self.productType = productType
             self.productName = name

Sources/Xcodeproj/XcodeProjectModelSerialization.swift

@@ -470,19 +470,19 @@ fileprivate class PropertyListSerializer {
     /// dictionary is what gets written to the property list.
     var idsToDicts = [String: PropertyList]()
 
-    /// Returns the identifier for the object, assigning one if needed.
+    /// Returns the quoted identifier for the object, assigning one if needed.
     func id(of object: PropertyListSerializable) -> String {
         // We need a "serialized object ref" wrapper for the `objsToIds` map.
         let serObjRef = SerializedObjectRef(object)
         if let id = objsToIds[serObjRef] {
-            return id
+            return "\"\(id)\""
         }
         // We currently always assign identifiers starting at 1 and going up.
         // FIXME: This is a suboptimal format for object identifier strings;
         // for debugging purposes they should at least sort in numeric order.
-        let id = "OBJ_\(objsToIds.count + 1)"
+        let id = object.objectID ?? "OBJ_\(objsToIds.count + 1)"
         objsToIds[serObjRef] = id
-        return id
+        return "\"\(id)\""
     }
 
     /// Serializes `object` by asking it to construct a plist dictionary and
@@ -546,13 +546,24 @@ fileprivate protocol PropertyListSerializable: class {
     /// matters.  So this is acceptable for now in the interest of getting it
     /// done.
 
+    /// A custom ID to use for the instance, if enabled.
+    ///
+    /// This ID must be unique across the entire serialized graph.
+    var objectID: String? { get }
+    
     /// Should create and return a property list dictionary of the object's
     /// attributes.  This function may also use the serializer's `serialize()`
     /// function to serialize other objects, and may use `id(of:)` to access
     /// ids of objects that either have or will be serialized.
     func serialize(to serializer: PropertyListSerializer) -> [String: PropertyList]
 }
 
+extension PropertyListSerializable {
+    var objectID: String? {
+        return nil
+    }
+}
+
 /// A very simple representation of a property list.  Note that the `identifier`
 /// enum is not strictly necessary, but useful to semantically distinguish the
 /// strings that represents object identifiers from those that are just data.

Sources/Xcodeproj/pbxproj().swift

@@ -194,6 +194,20 @@ func xcodeProject(
     // Determine the list of external package dependencies, if any.
     let externalPackages = graph.packages.filter({ !graph.rootPackages.contains($0) })
 
+    // Build a backmap of targets and products to packages.
+    var packagesByTarget = [ResolvedTarget: ResolvedPackage]()
+    for package in graph.packages {
+        for target in package.targets {
+            packagesByTarget[target] = package
+        }
+    }
+    var packagesByProduct = [ResolvedProduct: ResolvedPackage]()
+    for package in graph.packages {
+        for product in package.products {
+            packagesByProduct[product] = package
+        }
+    }
+    
     // To avoid creating multiple groups for the same path, we keep a mapping
     // of the paths we've seen and the corresponding groups we've created.
     var srcPathsToGroups: [AbsolutePath: Xcode.Group] = [:]
@@ -351,7 +365,10 @@ func xcodeProject(
         }
 
         // Create a Xcode target for the target.
-        let xcodeTarget = project.addTarget(productType: productType, name: target.name)
+        let package = packagesByTarget[target]!
+        let xcodeTarget = project.addTarget(
+            objectID: "\(package.name)::\(target.name)",
+            productType: productType, name: target.name)
 
         // Set the product name to the C99-mangled form of the target name.
         xcodeTarget.productName = target.c99name
@@ -427,7 +444,7 @@ func xcodeProject(
         targetSettings.common.FRAMEWORK_SEARCH_PATHS = ["$(inherited)", "$(PLATFORM_DIR)/Developer/Library/Frameworks"]
 
         // Add a file reference for the target's product.
-        let productRef = productsGroup.addFileReference(path: target.productPath.asString, pathBase: .buildDir)
+        let productRef = productsGroup.addFileReference(path: target.productPath.asString, pathBase: .buildDir, objectID: "\(package.name)::\(target.name)::Product")
 
         // Set that file reference as the target's product reference.
         xcodeTarget.productReference = productRef
@@ -556,7 +573,10 @@ func xcodeProject(
         // Go on to next product if we already have a target with the same name.
         if targetNames.contains(product.name) { continue }
         // Otherwise, create an aggreate target.
-        let aggregateTarget = project.addTarget(productType: nil, name: product.name)
+        let package = packagesByProduct[product]!
+        let aggregateTarget = project.addTarget(
+            objectID: "\(package.name)::\(product.name)::ProductTarget",
+            productType: nil, name: product.name)
         // Add dependencies on the targets created for each of the dependencies.
         for target in product.targets {
             // Find the target that corresponds to the target.  There might not