From 16038b8f82d0f3f610d97d721c39d6585fe90295 Mon Sep 17 00:00:00 2001
From: Benjamin Lupton <b@lupton.cc>
Date: Thu, 25 Jun 2020 21:18:01 +1000
Subject: [PATCH] fix(std/node/process): env, argv exports (#6455)

The promise approach still required permissions to be specified
at initialisation, rather than at request.

Using a Proxy instance solves this permission issue.

The Proxy instance approach also eliminates the need for the
await. Achieving direct compatibility with Node.js.

/ref pr #6392
/ref commit d16337cc9c59732fe81655482e08b72d844472e6
---
 std/node/process.ts      | 51 ++++++++++++++++++++++------------------
 std/node/process_test.ts |  8 +++----
 2 files changed, 32 insertions(+), 27 deletions(-)

diff --git a/std/node/process.ts b/std/node/process.ts
index 12cd1b4a94..ce5f828c07 100644
--- a/std/node/process.ts
+++ b/std/node/process.ts
@@ -28,7 +28,7 @@ export const versions = {
 };
 
 /** https://nodejs.org/api/process.html#process_process */
-// @deprecated exported only for backwards compatibility with old deno versions
+// @deprecated `import { process } from 'process'` for backwards compatibility with old deno versions
 export const process = {
   arch,
   chdir,
@@ -40,43 +40,48 @@ export const process = {
   versions,
 
   /** https://nodejs.org/api/process.html#process_process_events */
-  // node --input-type=module -e "import {on} from 'process'; console.log(on)"
-  // on is not exported by node, it is only available within process
+  // on is not exported by node, it is only available within process:
+  // node --input-type=module -e "import { on } from 'process'; console.log(on)"
   on(_event: string, _callback: Function): void {
     // TODO(rsp): to be implemented
     notImplemented();
   },
 
-  /** https://nodejs.org/api/process.html#process_process_env */
-  get env(): { [index: string]: string } {
-    // using getter to avoid --allow-env unless it's used
-    return Deno.env.toObject();
-  },
-
   /** https://nodejs.org/api/process.html#process_process_argv */
   get argv(): string[] {
-    // Deno.execPath() also requires --allow-env
+    // Getter delegates --allow-env and --allow-read until request
+    // Getter also allows the export Proxy instance to function as intended
     return [Deno.execPath(), ...Deno.args];
   },
+
+  /** https://nodejs.org/api/process.html#process_process_env */
+  get env(): { [index: string]: string } {
+    // Getter delegates --allow-env and --allow-read until request
+    // Getter also allows the export Proxy instance to function as intended
+    return Deno.env.toObject();
+  },
 };
 
-// define the type for configuring the env and argv promises
-// as well as for the global.process declaration
-type Process = typeof process;
+/**
+ * https://nodejs.org/api/process.html#process_process_argv
+ * @example `import { argv } from './std/node/process.ts'; console.log(argv)`
+ */
+// Proxy delegates --allow-env and --allow-read to request time, even for exports
+export const argv = new Proxy(process.argv, {});
 
-/** requires the use of await for compatibility with deno */
-export const env = new Promise<Process["env"]>((resolve) =>
-  resolve(process.env)
-);
+/**
+ * https://nodejs.org/api/process.html#process_process_env
+ * @example `import { env } from './std/node/process.ts'; console.log(env)`
+ */
+// Proxy delegates --allow-env and --allow-read to request time, even for exports
+export const env = new Proxy(process.env, {});
 
-/** requires the use of await for compatibility with deno */
-export const argv = new Promise<Process["argv"]>((resolve) =>
-  resolve(process.argv)
-);
-
-/** use this for access to `process.env` and `process.argv` without the need for await */
+// import process from './std/node/process.ts'
 export default process;
 
+// Define the type for the global declration
+type Process = typeof process;
+
 Object.defineProperty(process, Symbol.toStringTag, {
   enumerable: false,
   writable: true,
diff --git a/std/node/process_test.ts b/std/node/process_test.ts
index 043a954f8c..c4332af335 100644
--- a/std/node/process_test.ts
+++ b/std/node/process_test.ts
@@ -102,9 +102,9 @@ Deno.test({
 
 Deno.test({
   name: "process.argv",
-  async fn() {
+  fn() {
     assert(Array.isArray(process.argv));
-    assert(Array.isArray(await argv));
+    assert(Array.isArray(argv));
     assert(
       process.argv[0].match(/[^/\\]*deno[^/\\]*$/),
       "deno included in the file name of argv[0]"
@@ -115,8 +115,8 @@ Deno.test({
 
 Deno.test({
   name: "process.env",
-  async fn() {
+  fn() {
     assertEquals(typeof process.env.PATH, "string");
-    assertEquals(typeof (await env).PATH, "string");
+    assertEquals(typeof env.PATH, "string");
   },
 });