feat(runtime-adapters): Enable TypeScript decorator support for Deno and Bun runtimes and add decorator tests

bunfig.toml

@@ -0,0 +1,13 @@
+# Bun configuration for tstest
+# This enables TypeScript decorator support in Bun runtime
+
+[build]
+target = "bun"
+
+[test]
+preload = []
+
+# Enable decorators for Bun's TypeScript transpiler
+# This ensures user code with decorators works when executed via Bun
+[transpiler]
+experimentalDecorators = true

changelog.md

@@ -1,5 +1,14 @@
 # Changelog
 
+## 2025-11-17 - 2.8.0 - feat(runtime-adapters)
+Enable TypeScript decorator support for Deno and Bun runtimes and add decorator tests
+
+- Add bunfig.toml to enable experimentalDecorators for Bun runtime
+- Add deno.json to enable experimentalDecorators and set target/lib for Deno
+- Update Bun runtime adapter to note bunfig.toml discovery so Bun runs with decorator support
+- Update Deno runtime adapter to auto-detect deno.json / deno.jsonc and pass configPath in default options
+- Add integration tests for decorators (test/decorator.all.ts) to verify decorator support across runtimes
+
 ## 2025-10-26 - 2.7.0 - feat(tapbundle_protocol)
 Add package export for tapbundle_protocol to expose protocol utilities
 

deno.json

@@ -0,0 +1,8 @@
+{
+  "compilerOptions": {
+    "experimentalDecorators": true,
+    "lib": ["ES2022", "DOM"],
+    "target": "ES2022"
+  },
+  "nodeModulesDir": true
+}

test/decorator.all.ts

@@ -0,0 +1,91 @@
+import { tap, expect } from '../ts_tapbundle/index.js';
+
+/**
+ * Simple class decorator for testing decorator support across runtimes
+ */
+function testDecorator(target: any) {
+  target.decoratorApplied = true;
+  target.decoratorData = 'Decorator was applied successfully';
+  return target;
+}
+
+/**
+ * Method decorator for testing
+ */
+function logMethod(target: any, propertyKey: string, descriptor: PropertyDescriptor) {
+  const originalMethod = descriptor.value;
+  descriptor.value = function (...args: any[]) {
+    const result = originalMethod.apply(this, args);
+    return `[logged] ${result}`;
+  };
+  return descriptor;
+}
+
+/**
+ * Parameter decorator for testing
+ */
+function validateParam(target: any, propertyKey: string, parameterIndex: number) {
+  // Mark that parameter validation decorator was applied
+  if (!target.decoratedParams) {
+    target.decoratedParams = {};
+  }
+  if (!target.decoratedParams[propertyKey]) {
+    target.decoratedParams[propertyKey] = [];
+  }
+  target.decoratedParams[propertyKey].push(parameterIndex);
+}
+
+/**
+ * Test class with decorators
+ */
+@testDecorator
+class TestClass {
+  public name: string = 'test';
+
+  @logMethod
+  public greet(message: string): string {
+    return `Hello, ${message}!`;
+  }
+
+  public getValue(): number {
+    return 42;
+  }
+
+  public testParams(@validateParam value: string): string {
+    return value;
+  }
+}
+
+// Tests
+tap.test('Class decorator should be applied', async () => {
+  expect((TestClass as any).decoratorApplied).toEqual(true);
+  expect((TestClass as any).decoratorData).toEqual('Decorator was applied successfully');
+});
+
+tap.test('Method decorator should modify method behavior', async () => {
+  const instance = new TestClass();
+  const result = instance.greet('World');
+  expect(result).toEqual('[logged] Hello, World!');
+});
+
+tap.test('Regular methods should work normally', async () => {
+  const instance = new TestClass();
+  expect(instance.getValue()).toEqual(42);
+  expect(instance.name).toEqual('test');
+});
+
+tap.test('Parameter decorator should be applied', async () => {
+  const decoratedParams = (TestClass.prototype as any).decoratedParams;
+  expect(decoratedParams).toBeDefined();
+  expect(decoratedParams.testParams).toBeDefined();
+  expect(decoratedParams.testParams).toContain(0);
+});
+
+tap.test('Decorator metadata preservation', async () => {
+  const instance = new TestClass();
+  expect(instance instanceof TestClass).toEqual(true);
+  expect(instance.constructor.name).toEqual('TestClass');
+  expect(instance.testParams('hello')).toEqual('hello');
+});
+
+export default tap.start();

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@git.zone/tstest',
-  version: '2.7.0',
+  version: '2.8.0',
   description: 'a test utility to run tests that match test/**/*.ts'
 }

ts/tstest.classes.runtime.bun.ts

@@ -69,6 +69,9 @@ export class BunRuntimeAdapter extends RuntimeAdapter {
 
     const args: string[] = ['run'];
 
+    // Note: Bun automatically discovers bunfig.toml in the current directory
+    // This ensures TypeScript decorator support is enabled if bunfig.toml is present
+
     // Add extra args
     if (mergedOptions.extraArgs && mergedOptions.extraArgs.length > 0) {
       args.push(...mergedOptions.extraArgs);

ts/tstest.classes.runtime.deno.ts

@@ -31,8 +31,20 @@ export class DenoRuntimeAdapter extends RuntimeAdapter {
    * Get default Deno options
    */
   protected getDefaultOptions(): DenoOptions {
+    // Auto-detect deno.json or deno.jsonc config file for TypeScript decorator support
+    let configPath: string | undefined;
+    const denoJsonPath = plugins.path.join(process.cwd(), 'deno.json');
+    const denoJsoncPath = plugins.path.join(process.cwd(), 'deno.jsonc');
+
+    if (plugins.smartfile.fs.fileExistsSync(denoJsonPath)) {
+      configPath = denoJsonPath;
+    } else if (plugins.smartfile.fs.fileExistsSync(denoJsoncPath)) {
+      configPath = denoJsoncPath;
+    }
+
     return {
       ...super.getDefaultOptions(),
+      configPath,
       permissions: [
         '--allow-read',
         '--allow-env',