cmsj · ghostflyby · Dec 28, 2025
diff --git a/Hammerspoon 2.xcodeproj/project.pbxproj b/Hammerspoon 2.xcodeproj/project.pbxproj
@@ -11,13 +11,14 @@
 		4F488B302E97E79800A2B5F4 /* Sparkle in Frameworks */ = {isa = PBXBuildFile; productRef = 4F488B2F2E97E79800A2B5F4 /* Sparkle */; };
 		4F59E3502EFC986100954462 /* hammerspoon.d.ts in Resources */ = {isa = PBXBuildFile; fileRef = 4F59E34F2EFC985500954462 /* hammerspoon.d.ts */; };
 		4F59E3512EFC986100954462 /* api.json in Resources */ = {isa = PBXBuildFile; fileRef = 4F59E34E2EFC984900954462 /* api.json */; };
+		EC3BA53B2F013CE0001291A0 /* InternalESModuleForSwiftJavaScriptCore in Frameworks */ = {isa = PBXBuildFile; productRef = EC3BA53A2F013CE0001291A0 /* InternalESModuleForSwiftJavaScriptCore */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
 		4F5641912E8333840099EB4C /* PBXContainerItemProxy */ = {
 			isa = PBXContainerItemProxy;
 			containerPortal = 4F56417B2E8333830099EB4C /* Project object */;
-			proxyType = 1;
+			proxyType = 0;
 			remoteGlobalIDString = 4F5641822E8333830099EB4C;
 			remoteInfo = "Hammerspoon 2";
 		};
@@ -59,6 +60,7 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				EC3BA53B2F013CE0001291A0 /* InternalESModuleForSwiftJavaScriptCore in Frameworks */,
 				4F488B302E97E79800A2B5F4 /* Sparkle in Frameworks */,
 				4F463EA02EA7A669000A2135 /* AXSwift in Frameworks */,
 			);
@@ -151,6 +153,7 @@
 			packageProductDependencies = (
 				4F488B2F2E97E79800A2B5F4 /* Sparkle */,
 				4F463E9F2EA7A669000A2135 /* AXSwift */,
+				EC3BA53A2F013CE0001291A0 /* InternalESModuleForSwiftJavaScriptCore */,
 			);
 			productName = "Hammerspoon 2";
 			productReference = 4F5641832E8333830099EB4C /* Hammerspoon 2.app */;
@@ -210,6 +213,7 @@
 			packageReferences = (
 				4F488B2E2E97E79800A2B5F4 /* XCRemoteSwiftPackageReference "Sparkle" */,
 				4F463E9E2EA7A669000A2135 /* XCRemoteSwiftPackageReference "AXSwift" */,
+				EC3BA5392F013CE0001291A0 /* XCRemoteSwiftPackageReference "InternalESModuleForSwiftJavaScriptCore" */,
 			);
 			preferredProjectObjectVersion = 77;
 			productRefGroup = 4F5641842E8333830099EB4C /* Products */;
@@ -261,7 +265,6 @@
 /* Begin PBXTargetDependency section */
 		4F5641922E8333840099EB4C /* PBXTargetDependency */ = {
 			isa = PBXTargetDependency;
-			target = 4F5641822E8333830099EB4C /* Hammerspoon 2 */;
 			targetProxy = 4F5641912E8333840099EB4C /* PBXContainerItemProxy */;
 		};
 /* End PBXTargetDependency section */
@@ -576,6 +579,14 @@
 				minimumVersion = 2.8.0;
 			};
 		};
+		EC3BA5392F013CE0001291A0 /* XCRemoteSwiftPackageReference "InternalESModuleForSwiftJavaScriptCore" */ = {
+			isa = XCRemoteSwiftPackageReference;
+			repositoryURL = "https://github.com/ghostflyby/InternalESModuleForSwiftJavaScriptCore";
+			requirement = {
+				kind = exactVersion;
+				version = 1.0.1;
+			};
+		};
 /* End XCRemoteSwiftPackageReference section */
 
 /* Begin XCSwiftPackageProductDependency section */
@@ -589,6 +600,11 @@
 			package = 4F488B2E2E97E79800A2B5F4 /* XCRemoteSwiftPackageReference "Sparkle" */;
 			productName = Sparkle;
 		};
+		EC3BA53A2F013CE0001291A0 /* InternalESModuleForSwiftJavaScriptCore */ = {
+			isa = XCSwiftPackageProductDependency;
+			package = EC3BA5392F013CE0001291A0 /* XCRemoteSwiftPackageReference "InternalESModuleForSwiftJavaScriptCore" */;
+			productName = InternalESModuleForSwiftJavaScriptCore;
+		};
 /* End XCSwiftPackageProductDependency section */
 	};
 	rootObject = 4F56417B2E8333830099EB4C /* Project object */;

diff --git a/Hammerspoon 2.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved b/Hammerspoon 2.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved
diff --git a/Hammerspoon 2/Engine/JSEngine.swift b/Hammerspoon 2/Engine/JSEngine.swift
@@ -6,6 +6,7 @@
 //
 
 import Foundation
+import InternalESModuleForSwiftJavaScriptCore
 import JavaScriptCore
 
 @_documentation(visibility: private)
@@ -15,6 +16,7 @@ class JSEngine {
     private(set) var id = UUID()
     private var vm: JSVirtualMachine?
     private var context: JSContext?
+    private var moduleLoader: MultiRootFSModuleLoader?
 
     // MARK: - Engine JavaScript component
     private func injectEngineJS() {
@@ -28,39 +30,11 @@ class JSEngine {
         }
     }
 
-    private func injectRequire() {
-        guard let context else {
-            AKError("require(): Cannot set require() before context is available. This is a bug.")
-            return
-        }
-
-        let require: @convention(block) (String) -> (JSValue?) = { path in
-            let expandedPath = NSString(string: path).expandingTildeInPath
-
-            // Return void or throw an error here.
-            guard FileManager.default.fileExists(atPath: expandedPath) else {
-                AKError("require(): \(expandedPath) could not be found. Current working directory is \(FileManager.default.currentDirectoryPath)")
-                return nil
-            }
-
-            let fileURL = URL(fileURLWithPath: expandedPath)
-
-            guard let fileContent = try? String(contentsOfFile: expandedPath, encoding: .utf8) else {
-                AKError("require(): Unable to read \(expandedPath)")
-                return nil
-            }
-
-            return context.evaluateScript(fileContent, withSourceURL: fileURL)
-        }
-
-        context.setObject(require, forKeyedSubscript: "require" as NSString)
-    }
-
     // MARK: - JSContext Managing
     private func createContext() throws(HammerspoonError) {
         AKTrace("createContext()")
         vm = JSVirtualMachine()
-        guard vm != nil else {
+        guard let vm else {
             throw HammerspoonError(.vmCreation, msg: "Unknown error (vm)")
         }
 
@@ -72,14 +46,21 @@ class JSEngine {
         id = UUID()
         context.name = "Hammerspoon \(id)"
 
+        var baseURLs = [
+            URL(fileURLWithPath: FileManager.default.currentDirectoryPath, isDirectory: true)
+        ]
+        if let bundleURL = Bundle.main.resourceURL {
+            baseURLs.append(bundleURL)
+        }
+        let moduleLoader = MultiRootFSModuleLoader(virtualMachine: vm, baseURLs: baseURLs)
+        self.moduleLoader = moduleLoader
+        context.moduleLoaderDelegate = moduleLoader
+
         // This is our startup sequence.
 
         // First ensure the console namespace is populated
         self["console"] = ConsoleModule()
 
-        // Now ensure that require() exists
-        injectRequire()
-
         // Inject custom types we want to bridge between JS and Swift
         context.injectTypeBridges()
 
@@ -93,13 +74,16 @@ class JSEngine {
     private func deleteContext() {
         AKTrace("deleteContext()")
 
-        if let hs = self["hs"] as? JSValue, let moduleRoot = hs.toObjectOf(ModuleRoot.self) as? ModuleRoot {
+        if let hs = self["hs"] as? JSValue,
+            let moduleRoot = hs.toObjectOf(ModuleRoot.self) as? ModuleRoot
+        {
             moduleRoot.shutdown()
             self["hs"] = nil
         }
 
         context = nil
         vm = nil
+        moduleLoader = nil
     }
 }
 
@@ -125,8 +109,39 @@ extension JSEngine: JSEngineProtocol {
             throw HammerspoonError(.jsEvalURLKind, msg: "Refusing to eval remote URL")
         }
 
-        let script = try String(contentsOf: url, encoding: .utf8)
-        return context?.evaluateScript(script, withSourceURL: url)
+        guard let context else {
+            throw HammerspoonError(.unknown, msg: "JavaScript context is not available")
+        }
+        do {
+            guard let module = try moduleLoader?.module(for: url) else {
+                throw HammerspoonError(.jsModuleEvaluation, msg: "Unable to resolve module URL")
+            }
+            return try context.evaluate(esModule: module)
+        } catch {
+            throw HammerspoonError(.jsModuleEvaluation, msg: "\(error)")
+        }
+
+    }
+
+    @discardableResult func evalFromURL(_ url: URL) async throws -> Any? {
+        guard url.isFileURL else {
+            throw HammerspoonError(.jsEvalURLKind, msg: "Refusing to eval remote URL")
+        }
+
+        guard let context else {
+            throw HammerspoonError(.unknown, msg: "JavaScript context is not available")
+        }
+        do {
+            guard let module = try moduleLoader?.module(for: url) else {
+                throw HammerspoonError(.jsModuleEvaluation, msg: "Unable to resolve module URL")
+            }
+            let promise = try context.evaluate(esModule: module)
+            try await awaitPromise(promise, in: context)
+            return promise
+        } catch {
+            throw HammerspoonError(.jsModuleEvaluation, msg: "\(error)")
+        }
+
     }
 
     func resetContext() throws {
@@ -140,5 +155,29 @@ extension JSEngine: JSEngineProtocol {
     func hasContext() -> Bool {
         return vm != nil || context != nil
     }
+
+    private func awaitPromise(_ value: JSValue, in context: JSContext) async throws {
+        guard value.hasProperty("then") else {
+            throw PromiseAwaitError.invalidPromise
+        }
+        return try await withCheckedThrowingContinuation { continuation in
+            let resolve: @convention(block) (JSValue) -> Void = { _ in
+                continuation.resume()
+            }
+            let reject: @convention(block) (JSValue) -> Void = { error in
+                let message = error.toString() ?? "Promise rejected"
+                continuation.resume(throwing: PromiseAwaitError.rejected(message))
+            }
+            let resolveValue = JSValue(object: resolve, in: context)
+            let rejectValue = JSValue(object: reject, in: context)
+            _ = value.invokeMethod(
+                "then", withArguments: [resolveValue as Any, rejectValue as Any])
+        }
+    }
 }
 
+@_documentation(visibility: private)
+enum PromiseAwaitError: Error {
+    case invalidPromise
+    case rejected(String)
+}
diff --git a/Hammerspoon 2/Engine/MultiRootFSModuleLoader.swift b/Hammerspoon 2/Engine/MultiRootFSModuleLoader.swift
@@ -0,0 +1,126 @@
+//
+//  MultiRootFSModuleLoader.swift
+//  Hammerspoon 2
+//
+//  Created by Codex on 28/12/2025.
+//
+
+import Foundation
+import InternalESModuleForSwiftJavaScriptCore
+import JavaScriptCore
+
+@_documentation(visibility: private)
+final class MultiRootFSModuleLoader: ESModuleLoaderDelegate {
+    private let virtualMachine: JSVirtualMachine
+    private var baseRoots: [URL]
+    private var moduleCache: [URL: ESModuleScript] = [:]
+
+    init(virtualMachine: JSVirtualMachine, baseURLs: [URL]) {
+        self.virtualMachine = virtualMachine
+        self.baseRoots = baseURLs.map { $0.standardizedFileURL }
+    }
+
+    func module(for url: URL) throws -> ESModuleScript? {
+        guard let moduleURL = resolveModuleURL(url: url) else {
+            return nil
+        }
+
+        if let cached = moduleCache[moduleURL] {
+            return cached
+        }
+
+        let source = try String(contentsOf: moduleURL, encoding: .utf8)
+        let module = try ESModuleScript(
+            withSource: source,
+            andSourceURL: moduleURL,
+            andBytecodeCache: nil,
+            inVirtualMachine: virtualMachine
+        )
+        moduleCache[moduleURL] = module
+        return module
+    }
+
+    func fetchModule(
+        in context: JSContext,
+        identifier: String,
+        resolve: @escaping (ESModuleScript) -> Void,
+        reject: @escaping (JSValue) -> Void
+    ) {
+        guard let moduleURL = resolveModuleURL(identifier: identifier) else {
+            reject(
+                JSValue(
+                    newErrorFromMessage: "Unable to resolve module identifier: \(identifier)",
+                    in: context))
+            return
+        }
+
+        do {
+            guard let module = try module(for: moduleURL) else {
+                reject(
+                    JSValue(
+                        newErrorFromMessage: "Unable to resolve module URL: \(moduleURL.path)",
+                        in: context))
+                return
+            }
+            resolve(module)
+        } catch {
+            reject(
+                JSValue(
+                    newErrorFromMessage: "Unable to load module \(moduleURL.path): \(error)",
+                    in: context))
+        }
+    }
+
+    private func resolveModuleURL(identifier: String) -> URL? {
+        let candidate: URL
+        if let url = URL(string: identifier), url.scheme != nil {
+            guard url.isFileURL else {
+                return nil
+            }
+            candidate = url
+        } else {
+            let expandedPath = NSString(string: identifier).expandingTildeInPath
+            if expandedPath.hasPrefix("/") {
+                candidate = URL(fileURLWithPath: expandedPath)
+            } else {
+                for root in baseRoots {
+                    let probe = URL(fileURLWithPath: expandedPath, relativeTo: root)
+                        .standardizedFileURL
+                    if isWithinAllowedRoots(probe)
+                        && FileManager.default.fileExists(atPath: probe.path)
+                    {
+                        return probe
+                    }
+                }
+                return nil
+            }
+        }
+
+        let normalized = candidate.standardizedFileURL
+        return isWithinAllowedRoots(normalized) ? normalized : nil
+    }
+
+    private func resolveModuleURL(url: URL) -> URL? {
+        guard url.isFileURL else {
+            return nil
+        }
+        let normalized = url.standardizedFileURL
+        return isWithinAllowedRoots(normalized) ? normalized : nil
+    }
+
+    private func isWithinAllowedRoots(_ url: URL) -> Bool {
+        let path = url.path
+        for root in baseRoots {
+            let rootPath = root.path
+            let prefix = rootPath.hasSuffix("/") ? rootPath : rootPath + "/"
+            if path == rootPath || path.hasPrefix(prefix) {
+                return true
+            }
+        }
+        return false
+    }
+
+    func willEvaluateModule(at key: URL) {
+
+    }
+}