[PackageLoading] Recognize some Xcode filetypes

<rdar://problem/59725095>

Most of these can be now used when passing --build-system xcode

Author: aciidgh

Sources/PackageLoading/TargetSourcesBuilder.swift

@@ -66,7 +66,7 @@ public struct TargetSourcesBuilder {
         self.defaultLocalization = defaultLocalization
         self.diags = diags
         self.targetPath = path
-        self.rules = FileRuleDescription.builtinRules + additionalFileRules
+        self.rules = FileRuleDescription.builtinRules
         self.toolsVersion = toolsVersion
         self.fs = fs
         let excludedPaths = target.exclude.map{ path.appending(RelativePath($0)) }
@@ -515,13 +515,47 @@ public struct FileRuleDescription {
         )
     }()
 
+    /// File types related to the interface builder and storyboards.
+    public static var xib: FileRuleDescription = {
+        .init(
+            rule: .processResource,
+            toolsVersion: .vNext,
+            fileTypes: ["nib", "xib", "storyboard"]
+        )
+    }()
+
+    /// File types related to the asset catalog.
+    public static var assetCatalog: FileRuleDescription = {
+        .init(
+            rule: .processResource,
+            toolsVersion: .vNext,
+            fileTypes: ["xcassets"]
+        )
+    }()
+
+    /// File types related to the CoreData.
+    public static var coredata: FileRuleDescription = {
+        .init(
+            rule: .processResource,
+            toolsVersion: .vNext,
+            fileTypes: ["xcdatamodeld", "xcdatamodel", "xcmappingmodel"]
+        )
+    }()
+
     /// List of all the builtin rules.
     public static let builtinRules: [FileRuleDescription] = [
         swift,
         clang,
         asm,
         modulemap,
         header,
+    ] + xcbuildFileTypes
+
+    /// List of file types that requires the Xcode build system.
+    public static let xcbuildFileTypes: [FileRuleDescription] = [
+        xib,
+        assetCatalog,
+        coredata,
     ]
 }
 

Tests/PackageLoadingTests/PackageBuilderTests.swift

@@ -1895,6 +1895,34 @@ class PackageBuilderTests: XCTestCase {
             diagnostics.check(diagnostic: "manifest property 'defaultLocalization' not set; it is required in the presence of localized resources", behavior: .error)
         }
     }
+
+    func testXcodeResources() throws {
+        let fs = InMemoryFileSystem(emptyFiles:
+            "/Foo/Sources/Foo/foo.swift",
+            "/Foo/Sources/Foo/Foo.xcassets",
+            "/Foo/Sources/Foo/Foo.xib",
+            "/Foo/Sources/Foo/Foo.xcdatamodel"
+        )
+
+        let manifest = Manifest.createManifest(
+            name: "Foo",
+            v: .vNext,
+            targets: [
+                TargetDescription(name: "Foo"),
+            ]
+        )
+
+        PackageBuilderTester(manifest, path: AbsolutePath("/Foo"), in: fs) { result, diagnostics in
+            result.checkModule("Foo") { result in
+                result.checkSources(sources: ["foo.swift"])
+                result.checkResources(resources: [
+                    "/Foo/Sources/Foo/Foo.xib",
+                    "/Foo/Sources/Foo/Foo.xcdatamodel",
+                    "/Foo/Sources/Foo/Foo.xcassets",
+                ])
+            }
+        }
+    }
 }
 
 extension PackageModel.Product: ObjectIdentifierProtocol {}
@@ -2047,6 +2075,10 @@ final class PackageBuilderTester {
             checkSources(root: root, sources: paths, file: file, line: line)
         }
 
+        func checkResources(resources: [String], file: StaticString = #file, line: UInt = #line) {
+            XCTAssertEqual(Set(resources), Set(self.target.resources.map{ $0.path.pathString }), "unexpected resource files in \(target.name)", file: file, line: line)
+        }
+
         func check(targetDependencies depsToCheck: [String], file: StaticString = #file, line: UInt = #line) {
             XCTAssertEqual(Set(depsToCheck), Set(target.dependencies.compactMap { $0.target?.name }), "unexpected dependencies in \(target.name)", file: file, line: line)
         }