Engine API: Migrate WITOverlayGenerator

Author: kateinoigakukun

Sources/WITOverlayGenerator/HostGenerators/HostExportFunction.swift

@@ -252,23 +252,28 @@ struct HostExportFunction {
         )
         var signature = try signatureTranslation.signature(function: function, name: ConvertCase.camelCase(kebab: name.apiSwiftName))
         let witParameters = signature.parameters.map(\.label)
-        signature.parameters.insert(("runtime", "Runtime"), at: 0)
         signature.hasThrows = true
         printer.write(line: signature.description + " {")
         try printer.indent {
             let optionsVar = builder.variable("options")
             printer.write(line: "let \(optionsVar) = CanonicalOptions._derive(from: instance, exportName: \"\(name.abiName)\")")
-            printer.write(line: "let \(context.contextVar) = CanonicalCallContext(options: \(optionsVar), instance: instance, runtime: runtime)")
+            printer.write(line: "let \(context.contextVar) = CanonicalCallContext(options: \(optionsVar), instance: instance)")
             // Suppress unused variable warning for "context"
             printer.write(line: "_ = \(context.contextVar)")
 
             let arguments = try printLowerArguments(
                 parameterNames: witParameters, coreSignature: coreSignature,
                 typeResolver: typeResolver, printer: printer
             )
-            var call = "try runtime.invoke(instance, function: \"\(name.abiName)\""
+            let functionVar = builder.variable("function")
+            printer.write(multiline: """
+            guard let \(functionVar) = instance.exports[function: \"\(name.abiName)\"] else {
+                throw CanonicalABIError(description: "Function \\"\(name.abiName)\\" not found in the instance")
+            }
+            """)
+            var call = "try \(functionVar)("
             if !arguments.isEmpty {
-                call += ", with: [\(arguments.map(\.description).joined(separator: ", "))]"
+                call += "[\(arguments.map(\.description).joined(separator: ", "))]"
             }
             call += ")"
             if coreSignature.isIndirectResult {

Sources/WasmKit/Component/CanonicalCall.swift

@@ -1,7 +1,13 @@
 @_exported import WasmTypes
 
-struct CanonicalABIError: Error, CustomStringConvertible {
-    let description: String
+/// Error type for canonical ABI operations.
+public struct CanonicalABIError: Error, CustomStringConvertible {
+    public let description: String
+
+    @_documentation(visibility: internal)
+    public init(description: String) {
+        self.description = description
+    }
 }
 
 /// Call context for `(canon lift)` or `(canon lower)` operations.
@@ -14,17 +20,14 @@ public struct CanonicalCallContext {
     public let options: CanonicalOptions
     /// The module instance that defines the lift/lower operation.
     public let instance: Instance
-    /// The executing `Runtime` instance
-    public let runtime: Runtime
     /// A reference to the guest memory.
     public var guestMemory: Memory {
         options.memory
     }
 
-    public init(options: CanonicalOptions, instance: Instance, runtime: Runtime) {
+    public init(options: CanonicalOptions, instance: Instance) {
         self.options = options
         self.instance = instance
-        self.runtime = runtime
     }
 
     /// Call `cabi_realloc` export with the given arguments.
@@ -56,9 +59,9 @@ extension CanonicalCallContext {
         return instance
     }
 
-    @available(*, deprecated, renamed: "init(options:instance:runtime:)")
+    @available(*, deprecated, renamed: "init(options:instance:)")
     public init(options: CanonicalOptions, moduleInstance: Instance, runtime: Runtime) {
-        self.init(options: options, instance: moduleInstance, runtime: runtime)
+        self.init(options: options, instance: moduleInstance)
     }
 }
 

Sources/WasmKit/Component/CanonicalOptions.swift

@@ -35,13 +35,13 @@ public struct CanonicalOptions {
     /// FIXME: This deriviation is wrong because the options should be determined by `(canon lift)` or `(canon lower)`
     /// in an encoded component at componetizing-time. (e.g. wit-component tool is one of the componetizers)
     /// Remove this temporary method after we will accept binary form of component file.
-    public static func _derive(from moduleInstance: Instance, exportName: String) -> CanonicalOptions {
-        guard case let .memory(memory) = moduleInstance.exports["memory"] else {
+    public static func _derive(from instance: Instance, exportName: String) -> CanonicalOptions {
+        guard case let .memory(memory) = instance.exports["memory"] else {
             fatalError("Missing required \"memory\" export")
         }
         return CanonicalOptions(
             memory: memory, stringEncoding: .utf8,
-            realloc: moduleInstance.exportedFunction(name: "cabi_realloc"),
-            postReturn: moduleInstance.exportedFunction(name: "cabi_post_\(exportName)"))
+            realloc: instance.exportedFunction(name: "cabi_realloc"),
+            postReturn: instance.exportedFunction(name: "cabi_post_\(exportName)"))
     }
 }

Sources/WasmKit/Execution/Runtime.swift

@@ -1,6 +1,7 @@
 import WasmParser
 
 /// A container to manage execution state of one or more module instances.
+@available(*, deprecated, message: "Use `Engine` instead")
 public final class Runtime {
     public let store: Store
     let engine: Engine
@@ -24,7 +25,6 @@ public final class Runtime {
     /// - Parameter hostModules: Host module names mapped to their corresponding ``HostModule`` definitions.
     /// - Parameter interceptor: An optional runtime interceptor to intercept execution of instructions.
     /// - Parameter configuration: An optional runtime configuration to customize the runtime behavior.
-    @available(*, deprecated)
     public init(
         hostModules: [String: HostModule] = [:],
         interceptor: EngineInterceptor? = nil,
@@ -44,9 +44,7 @@ public final class Runtime {
     func internType(_ type: FunctionType) -> InternedFuncType {
         return funcTypeInterner.intern(type)
     }
-}
 
-extension Runtime {
     public func instantiate(module: Module) throws -> Instance {
         return try module.instantiate(
             store: store,
@@ -137,9 +135,7 @@ extension Runtime {
 
         return result
     }
-}
 
-extension Runtime {
     @available(*, unavailable, message: "Runtime doesn't manage execution state anymore. Use Execution.step instead")
     public func step() throws {
         fatalError()

Sources/WasmKitWASI/WASIBridgeToHost+WasmKit.swift

@@ -47,6 +47,7 @@ extension WASIBridgeToHost {
         return 0
     }
 
+    @available(*, deprecated, message: "Use `Engine`-based API instead")
     public func start(_ instance: Instance, runtime: Runtime) throws -> UInt32 {
         return try start(instance)
     }

Tests/WITOverlayGeneratorTests/Runtime/RuntimeSmokeTests.swift

@@ -8,7 +8,7 @@ class RuntimeSmokeTests: XCTestCase {
         var harness = try RuntimeTestHarness(fixture: "Smoke")
         try harness.build(link: SmokeTestWorld.link(_:)) { (runtime, instance) in
             let component = SmokeTestWorld(instance: instance)
-            _ = try component.hello(runtime: runtime)
+            _ = try component.hello()
         }
     }
 }