Implement import.meta

Closes #26.

.changeset/honest-geckos-lie.md

@@ -0,0 +1,5 @@
+---
+'nxjs-runtime': patch
+---
+
+Implement `import.meta`

apps/tests/package.json

@@ -5,7 +5,7 @@
   "type": "module",
   "description": "nx.js API tests",
   "scripts": {
-    "build": "esbuild --bundle --target=es2020 src/main.ts --outfile=romfs/main.js",
+    "build": "esbuild --bundle --target=es2020 --format=esm src/main.ts --outfile=romfs/main.js",
     "nro": "nxjs-pack"
   },
   "license": "MIT",

apps/tests/src/import.ts

@@ -0,0 +1,20 @@
+import { suite } from 'uvu';
+import * as assert from 'uvu/assert';
+
+const test = suite('import');
+
+test('`import.meta.url` is a string', () => {
+	assert.type(import.meta.url, 'string');
+
+	// This should match the esbuild bundle output file name
+	assert.equal(new URL(import.meta.url).href, Switch.entrypoint);
+});
+
+test('`import.meta.main` is a boolean', () => {
+	assert.type(import.meta.main, 'boolean');
+
+	// This should be `true` since esbuild is used to bundle
+	assert.equal(import.meta.main, true);
+});
+
+test.run();

apps/tests/src/main.ts

@@ -1,5 +1,6 @@
 import './canvas';
 import './fetch';
 import './form-data';
+import './import';
 import './switch';
 import './wasm';

apps/tests/tsconfig.json

@@ -1,6 +1,7 @@
 {
   "compilerOptions": {
     "target": "ES2020",
+    "module": "ES2020",
     "moduleResolution": "Bundler",
     "noEmit": true,
     "forceConsistentCasingInFileNames": true,

packages/runtime/src/index.ts

@@ -79,6 +79,24 @@ import './navigator';
 import * as WebAssembly from './wasm';
 def('WebAssembly', WebAssembly);
 
+/**
+ * The `import.meta` meta-property exposes context-specific metadata to a JavaScript module.
+ * It contains information about the module, such as the module's URL.
+ */
+export interface ImportMeta {
+	/**
+	 * Contains the absolute URL of the JavaScript module that is being executed.
+	 *
+	 * @example "romfs:/main.js"
+	 */
+	url: string;
+	/**
+	 * Set to `true` when the JavaScript module that is being executed is the
+	 * entrypoint file of the application.
+	 */
+	main: boolean;
+}
+
 function touchIsEqual(a: Touch, b: Touch) {
 	return (
 		a.screenX === b.screenX &&

source/main.c

@@ -384,6 +384,23 @@ static JSValue js_get_internal_promise_state(JSContext *ctx, JSValueConst this_v
     return arr;
 }
 
+int nx_module_set_import_meta(JSContext *ctx, JSValueConst func_val,
+                              const char *url, JS_BOOL is_main)
+{
+    JSModuleDef *m = JS_VALUE_GET_PTR(func_val);
+    JSValue meta_obj = JS_GetImportMeta(ctx, m);
+    if (JS_IsException(meta_obj))
+        return -1;
+    JS_DefinePropertyValueStr(ctx, meta_obj, "url",
+                              JS_NewString(ctx, url),
+                              JS_PROP_C_W_E);
+    JS_DefinePropertyValueStr(ctx, meta_obj, "main",
+                              JS_NewBool(ctx, is_main),
+                              JS_PROP_C_W_E);
+    JS_FreeValue(ctx, meta_obj);
+    return 0;
+}
+
 void nx_process_pending_jobs(JSRuntime *rt)
 {
     JSContext *ctx;
@@ -578,12 +595,22 @@ int main(int argc, char *argv[])
     JS_SetPropertyStr(ctx, switch_obj, "argv", argv_array);
 
     // Run the user code
-    JSValue user_code_result = JS_Eval(ctx, user_code, user_code_size, js_path, JS_EVAL_TYPE_GLOBAL);
+    JSValue user_code_result = JS_Eval(ctx, user_code, user_code_size, js_path, JS_EVAL_TYPE_MODULE | JS_EVAL_FLAG_COMPILE_ONLY);
     if (JS_IsException(user_code_result))
     {
         print_js_error(ctx);
         had_error = 1;
     }
+    else
+    {
+        nx_module_set_import_meta(ctx, user_code_result, js_path, true);
+        user_code_result = JS_EvalFunction(ctx, user_code_result);
+        if (JS_IsException(user_code_result))
+        {
+            print_js_error(ctx);
+            had_error = 1;
+        }
+    }
     JS_FreeValue(ctx, user_code_result);
     free(user_code);
     if (js_path_needs_free)