Parse the TargetResolver from assemblies

Example/KnitExample.xcodeproj/project.pbxproj

@@ -239,7 +239,7 @@
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "/usr/bin/xcrun --sdk macosx swift run knit gen \\\n--assembly-input-path KnitExample/KnitExampleAssembly.swift \\\n--assembly-input-path KnitExample/KnitExampleUserAssembly.swift \\\n--type-safety-extensions-output-path KnitExample/KnitDITypeSafety.swift \\\n--unit-test-output-path KnitExampleTests/KnitDIRegistrationTests.swift\n";
+			shellScript = "/usr/bin/xcrun --sdk macosx swift run knit-cli gen \\\n--assembly-input-path KnitExample/KnitExampleAssembly.swift \\\n--assembly-input-path KnitExample/KnitExampleUserAssembly.swift \\\n--type-safety-extensions-output-path KnitExample/KnitDITypeSafety.swift \\\n--unit-test-output-path KnitExampleTests/KnitDIRegistrationTests.swift\n";
 		};
 /* End PBXShellScriptBuildPhase section */
 

Example/KnitExample.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved

@@ -14,8 +14,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-syntax.git",
       "state" : {
-        "revision" : "2c49d66d34dfd6f8130afdba889de77504b58ec0",
-        "version" : "508.0.1"
+        "revision" : "6ad4ea24b01559dde0773e3d091f1b9e36175036",
+        "version" : "509.0.2"
       }
     },
     {

Sources/KnitCodeGen/AssemblyParsing.swift

@@ -2,7 +2,11 @@ import Foundation
 import SwiftSyntax
 import SwiftParser
 
-public func parseAssemblies(at paths: [String]) throws -> ConfigurationSet {
+public func parseAssemblies(
+    at paths: [String],
+    defaultTargetResolver: String,
+    useTargetResolver: Bool
+) throws -> ConfigurationSet {
     var configs = [Configuration]()
     for path in paths {
         let url = URL(fileURLWithPath: path, isDirectory: false)
@@ -15,7 +19,12 @@ public func parseAssemblies(at paths: [String]) throws -> ConfigurationSet {
             throw AssemblyParsingError.fileReadError(error, path: path)
         }
         let syntaxTree = Parser.parse(source: source)
-        let configuration = try parseSyntaxTree(syntaxTree, errorsToPrint: &errorsToPrint)
+        let configuration = try parseSyntaxTree(
+            syntaxTree,
+            errorsToPrint: &errorsToPrint,
+            defaultTargetResolver: defaultTargetResolver,
+            useTargetResolver: useTargetResolver
+        )
         configs.append(configuration)
         printErrors(errorsToPrint, filePath: path, syntaxTree: syntaxTree)
     }
@@ -24,7 +33,9 @@ public func parseAssemblies(at paths: [String]) throws -> ConfigurationSet {
 
 func parseSyntaxTree(
     _ syntaxTree: SyntaxProtocol,
-    errorsToPrint: inout [Error]
+    errorsToPrint: inout [Error],
+    defaultTargetResolver: String,
+    useTargetResolver: Bool
 ) throws -> Configuration {
     let assemblyFileVisitor = AssemblyFileVisitor()
     assemblyFileVisitor.walk(syntaxTree)
@@ -36,11 +47,19 @@ func parseSyntaxTree(
     errorsToPrint.append(contentsOf: assemblyFileVisitor.assemblyErrors)
     errorsToPrint.append(contentsOf: assemblyFileVisitor.registrationErrors)
 
+    let targetResolver: String
+    if useTargetResolver {
+        targetResolver = assemblyFileVisitor.targetResolver ?? defaultTargetResolver
+    } else {
+        targetResolver = defaultTargetResolver
+    }
+
     return Configuration(
         name: name,
         registrations: assemblyFileVisitor.registrations,
         registrationsIntoCollections: assemblyFileVisitor.registrationsIntoCollections,
-        imports: assemblyFileVisitor.imports
+        imports: assemblyFileVisitor.imports,
+        targetResolver: targetResolver
     )
 }
 
@@ -67,6 +86,10 @@ private class AssemblyFileVisitor: SyntaxVisitor {
         return classDeclVisitor?.registrationErrors ?? []
     }
 
+    var targetResolver: String? {
+        return classDeclVisitor?.targetResolver
+    }
+
     init() {
         super.init(viewMode: .fixedUp)
     }
@@ -116,6 +139,8 @@ private class ClassDeclVisitor: SyntaxVisitor {
 
     private(set) var registrationErrors = [Error]()
 
+    private(set) var targetResolver: String?
+
     init(viewMode: SyntaxTreeViewMode, directives: KnitDirectives) {
         self.directives = directives
         super.init(viewMode: viewMode)
@@ -138,6 +163,15 @@ private class ClassDeclVisitor: SyntaxVisitor {
         return .skipChildren
     }
 
+    override func visit(_ node: TypeAliasDeclSyntax) -> SyntaxVisitorContinueKind {
+        if node.name.text == "TargetResolver",
+           let identifier = node.initializer.value.as(IdentifierTypeSyntax.self) {
+            self.targetResolver = identifier.name.text
+        }
+
+        return .skipChildren
+    }
+
 }
 
 extension NamedDeclSyntax {

Sources/KnitCodeGen/Configuration.swift

@@ -10,17 +10,20 @@ public struct Configuration: Encodable {
     public var registrationsIntoCollections: [RegistrationIntoCollection]
 
     public var imports: [ImportDeclSyntax] = []
+    public var targetResolver: String
 
     public init(
         name: String,
         registrations: [Registration],
         registrationsIntoCollections: [RegistrationIntoCollection],
-        imports: [ImportDeclSyntax] = []
+        imports: [ImportDeclSyntax] = [],
+        targetResolver: String
     ) {
         self.name = name
         self.registrations = registrations
         self.registrationsIntoCollections = registrationsIntoCollections
         self.imports = imports
+        self.targetResolver = targetResolver
     }
 
     public enum CodingKeys: CodingKey {
@@ -35,7 +38,7 @@ public extension Configuration {
     func makeTypeSafetySourceFile() throws -> SourceFileSyntax {
         return try TypeSafetySourceFile.make(
             assemblyName: "\(name)Assembly",
-            extensionTarget: "Resolver",
+            extensionTarget: targetResolver,
             registrations: registrations
         )
     }

Sources/KnitCommand/GenCommand.swift

@@ -40,12 +40,23 @@ struct GenCommand: ParsableCommand {
                   """)
     var jsonDataOutputPath: String?
 
+    // This flag was added to allow backwards compatibility. This may prove to be unnecessary.
+    @Flag(help: "When parsing assembly files, generate type safe methods against the target resolver")
+    var useTargetResolver: Bool = false
+
+    @Option(help: "Default type to extend when generating Resolver type safety methods")
+    var defaultExtensionTargetResolver = "Resolver"
+
     public init() {}
 
     public func run() throws {
         let parsedConfig: ConfigurationSet
         do {
-            parsedConfig = try parseAssemblies(at: assemblyInputPath)
+            parsedConfig = try parseAssemblies(
+                at: assemblyInputPath,
+                defaultTargetResolver: defaultExtensionTargetResolver,
+                useTargetResolver: useTargetResolver
+            )
             if let jsonDataOutputPath {
                 let data = try JSONEncoder().encode(parsedConfig.assemblies)
                 try data.write(to: URL(fileURLWithPath: jsonDataOutputPath))

Tests/KnitCodeGenTests/AssemblyParsingTests.swift

@@ -177,6 +177,7 @@ final class AssemblyParsingTests: XCTestCase {
 
         let config = try assertParsesSyntaxTree(sourceFile)
         XCTAssertEqual(config.name, "Example")
+        XCTAssertEqual(config.targetResolver, "Resolver")
         XCTAssertEqual(
             config.registrations,
             [
@@ -244,17 +245,47 @@ final class AssemblyParsingTests: XCTestCase {
         )
     }
 
+    func testCustomResolver() throws {
+        let sourceFile: SourceFileSyntax = """
+            class MyAssembly: Assembly {
+                typealias TargetResolver = TestResolver
+            }
+        """
+
+        let config = try assertParsesSyntaxTree(sourceFile)
+        XCTAssertEqual(config.name, "My")
+        XCTAssertEqual(config.targetResolver, "TestResolver")
+    }
+
+    func testCustomResolverWhenDisabled() throws {
+        let sourceFile: SourceFileSyntax = """
+            class MyAssembly: Assembly {
+                typealias TargetResolver = TestResolver
+            }
+        """
+
+        let config = try assertParsesSyntaxTree(sourceFile, useTargetResolver: false)
+        XCTAssertEqual(config.name, "My")
+        XCTAssertEqual(config.targetResolver, "Resolver")
+    }
+
 }
 
 private func assertParsesSyntaxTree(
     _ sourceFile: SourceFileSyntax,
     assertErrorsToPrint assertErrorsCallback: (([Error]) -> Void)? = nil,
+    useTargetResolver: Bool = true,
     file: StaticString = #filePath,
     line: UInt = #line
 ) throws -> Configuration {
     var errorsToPrint = [Error]()
 
-    let configuration = try parseSyntaxTree(sourceFile, errorsToPrint: &errorsToPrint)
+    let configuration = try parseSyntaxTree(
+        sourceFile,
+        errorsToPrint: &errorsToPrint,
+        defaultTargetResolver: "Resolver",
+        useTargetResolver: useTargetResolver
+    )
 
     if let assertErrorsCallback {
         assertErrorsCallback(errorsToPrint)

Tests/KnitCodeGenTests/ConfigurationSetTests.swift

@@ -147,7 +147,8 @@ private enum Factory {
         ],
         imports: [
             .init(moduleName: "Dependency1")
-        ]
+        ],
+        targetResolver: "Resolver"
     )
 
     static let config2 = Configuration(
@@ -160,7 +161,8 @@ private enum Factory {
         registrationsIntoCollections: [],
         imports: [
             .init(moduleName: "Dependency2")
-        ]
+        ],
+        targetResolver: "Resolver"
     )
 
     static let config3 = Configuration(
@@ -171,6 +173,7 @@ private enum Factory {
         registrationsIntoCollections: [],
         imports: [
             .init(moduleName: "Dependency2")
-        ]
+        ],
+        targetResolver: "Resolver"
     )
 }

Tests/KnitCodeGenTests/UnitTestSourceFileTests.swift

@@ -213,7 +213,8 @@ private extension UnitTestSourceFile {
             name: name,
             registrations: registrations,
             registrationsIntoCollections: registrationsIntoCollections,
-            imports: importDecls
+            imports: importDecls,
+            targetResolver: "Resolver"
         )
         return try UnitTestSourceFile.make(configuration: configuration)
     }