From bcb02fd994997df13fe4f41737590b39c467df8c Mon Sep 17 00:00:00 2001
From: Benjamin Fischer <61995275+c4spar@users.noreply.github.com>
Date: Wed, 27 Apr 2022 22:34:13 +0200
Subject: [PATCH] refactor(runtime): make `$.mainModule`, `$.args` &
 `$.startTime` readonly (#32)

---
 src/cli/lib/bootstrap.ts | 48 +++++++++++++++++++++++++++++++---------
 src/cli/lib/worker.ts    |  2 --
 src/cli/mod.ts           |  3 +--
 src/runtime/mod.ts       | 13 +++++------
 4 files changed, 43 insertions(+), 23 deletions(-)

diff --git a/src/cli/lib/bootstrap.ts b/src/cli/lib/bootstrap.ts
index 22be5b8..8e622d3 100644
--- a/src/cli/lib/bootstrap.ts
+++ b/src/cli/lib/bootstrap.ts
@@ -1,8 +1,9 @@
 import { $ } from "../../runtime/mod.ts";
 
+const startTime = Date.now();
+
 export interface BootstrapOptions {
   code?: string;
-  startTime?: number;
   mainModule?: string;
   args?: Array<string> | string;
   base64?: boolean;
@@ -14,19 +15,32 @@ export function base64Module(code: string) {
 }
 
 export function stringifyArgs(args: Array<string>) {
-  return args?.length
-    ? `$.args = JSON.parse(decodeURIComponent("${
+  if (!args?.length) {
+    return "";
+  }
+  let code = args?.length
+    ? `const args = JSON.parse(decodeURIComponent("${
       encodeURIComponent(JSON.stringify(args))
-    }"));`
-    : "";
+    }"));\n`
+    : "const args = [];\n";
+  code += `Object.defineProperty($, "args", { get: () => args });`;
+  return code;
+}
+
+export function stringifyMainModule(mainModule: string) {
+  return `Object.defineProperty($, "mainModule", { get: () => "${mainModule}" });`;
+}
+
+export function stringifyStartTime(startTime: number) {
+  return `Object.defineProperty($, "startTime", { get: () => ${startTime} });`;
 }
 
 export function bootstrap(options: BootstrapOptions): string {
   const code = [
     `import "${new URL("../../../mod.ts", import.meta.url)}";`,
     "{",
-    options.startTime ? `$.startTime = ${options.startTime};` : "",
-    options.mainModule ? `$.mainModule = "${options.mainModule}";` : "",
+    stringifyStartTime(startTime),
+    options.mainModule ? stringifyMainModule(options.mainModule) : "",
     options.verbose !== undefined ? `$.verbose = ${options.verbose};` : "",
     typeof options.args === "string"
       ? options.args
@@ -78,14 +92,26 @@ export interface ImportModuleOptions {
 }
 
 export async function importModule(options: ImportModuleOptions) {
-  $.mainModule = options.mainModule;
-  if (options.args) {
-    $.args = options.args;
-  }
+  const mainModule = options.mainModule;
+  Object.defineProperty($, "mainModule", {
+    get: () => mainModule,
+  });
+
+  const args = options.args ? [...options.args] : [];
+  Object.defineProperty($, "args", {
+    get: () => args,
+  });
+
   if (typeof options.verbose !== "undefined") {
     $.verbose = options.verbose;
   }
+
+  Object.defineProperty($, "startTime", {
+    get: (): number => startTime,
+  });
+
   await import($.mainModule);
+
   if ($.verbose) {
     console.log($.bold("time: %ss"), Math.round($.time) / 1000);
   }
diff --git a/src/cli/lib/worker.ts b/src/cli/lib/worker.ts
index 35885b3..ff45785 100644
--- a/src/cli/lib/worker.ts
+++ b/src/cli/lib/worker.ts
@@ -17,7 +17,6 @@ export interface SpawnWorkerOptions extends Omit<BootstrapOptions, "base64"> {
 
 export function spawnWorker({
   args,
-  startTime,
   mainModule,
   perms,
   verbose,
@@ -25,7 +24,6 @@ export function spawnWorker({
   new Worker(
     bootstrapModule({
       args,
-      startTime,
       mainModule,
       verbose,
       base64: true,
diff --git a/src/cli/mod.ts b/src/cli/mod.ts
index ef3612c..a082bdf 100755
--- a/src/cli/mod.ts
+++ b/src/cli/mod.ts
@@ -1,5 +1,5 @@
 import { VERSION } from "../../version.ts";
-import { $, path } from "../runtime/mod.ts";
+import { path } from "../runtime/mod.ts";
 import { bundleCommand } from "./bundle.ts";
 import { compileCommand } from "./compile.ts";
 import {
@@ -107,7 +107,6 @@ export function dzx() {
             mainModule,
             args,
             verbose,
-            startTime: $.startTime,
           });
         } else {
           await importModule({ mainModule, args, verbose });
diff --git a/src/runtime/mod.ts b/src/runtime/mod.ts
index 9dbd862..91d047d 100644
--- a/src/runtime/mod.ts
+++ b/src/runtime/mod.ts
@@ -19,17 +19,17 @@ export { ProcessError } from "./process_error.ts";
 export { ProcessOutput } from "./process_output.ts";
 
 export type $ = typeof exec & typeof colors & {
-  shell: string;
-  prefix: string;
-  mainModule: string;
+  get mainModule(): string;
+  get args(): Array<string>;
   get verbose(): number;
   set verbose(value: boolean | number);
+  get startTime(): number;
+  shell: string;
+  prefix: string;
   stdout: NonNullable<Deno.RunOptions["stdout"]>;
   stderr: NonNullable<Deno.RunOptions["stderr"]>;
-  args: Array<string>;
   quote: typeof shq;
   throwErrors: boolean;
-  startTime: number;
   time: number;
 };
 
@@ -43,13 +43,10 @@ Object.setPrototypeOf($, Object.getPrototypeOf(colors));
 $._stack = [];
 $.shell = "/bin/bash";
 $.prefix = "set -euo pipefail;";
-$.mainModule = Deno.mainModule;
 $.stdout = "piped";
 $.stderr = "piped";
-$.args = [];
 $.quote = shq;
 $.throwErrors = false;
-$.startTime = Date.now();
 
 let _verbose = 1;
 Object.defineProperty($, "verbose", {