Build script: support Deno runtime (darkreader#10786)

 - adds Deno runtime as an alternative to Node.js
 - requires Deno canary and supports only building (not tests)
 - built output is the same between Node.js and Deno (which means build is reproducible)

Author: bershanskiy

.gitignore

@@ -33,3 +33,8 @@ coverage/
 # V8 Profiler logs
 #-----------------------------------
 isolate-*-v8.log
+
+# Deno
+#-----------------------------------
+deno.lock
+deno.json

README.md

@@ -20,6 +20,10 @@ Read more about contributing to Dark Reader in [CONTRIBUTING.md](https://github.
 
 ## Building for use
 
+Dark Reader build script requires a JavaScript runtime, either NodeJS or Deno. We recommend using NodeJS, Deno support is experimental.
+
+### Building with NodeJS
+
 You can install the extension from a file.
 Install [Node.js](https://nodejs.org/) (we recommend LTS or higher, but any version at or above 15 will work). Download the source code (or check out from git).
 Open the terminal in the root folder and run:
@@ -31,6 +35,12 @@ This will create a `build/release/darkreader-chrome.zip` file for use in a Chrom
 
 You can customize build process by passing flags to build script. To see all flags, run `npm run build -- --help`.
 
+### Building with Deno
+
+You can build Dark Reader with alternative runtime called [Deno](https://deno.land/). For this run `deno:bootstrap` script (e.g., via `npm run deno:bootstrap` or manually copy the command from `package.json`). Then run the same commands described above.
+
+Please note that if you encounter error `Too many open files (os error 24)`, then you should use the newer version of Deno (preferably built from source or canary).
+
 ## Using Dark Reader for a website
 
 You can use Dark Reader to enable dark mode on your website!

package.json

@@ -28,7 +28,8 @@
     "test:unit": "jest --config=tests/unit/jest.config.mjs",
     "test:unit:debug": "node --inspect-brk ./node_modules/jest/bin/jest --config=tests/unit/jest.config.mjs --runInBand --no-cache --watch",
     "test:update-snapshots": "npm run test -- --updateSnapshot && npm run test:project -- --updateSnapshot",
-    "translate-line": "node ./tasks/translate.js --line"
+    "translate-line": "node ./tasks/translate.js --line",
+    "deno:bootstrap": "deno run --allow-read=./ --allow-sys=uid --allow-write=deno.json tasks/deno.js"
   },
   "main": "darkreader.js",
   "repository": {

tasks/bundle-manifest.js

@@ -2,21 +2,11 @@
 import path from './paths.js';
 import * as reload from './reload.js';
 import {createTask} from './task.js';
-import {readFile, writeFile} from './utils.js';
+import {readJSON, writeJSON} from './utils.js';
 const {PLATFORM, getDestDir} = path;
 
 const srcDir = 'src';
 
-async function readJSON(path) {
-    const file = await readFile(path);
-    return JSON.parse(file);
-}
-
-async function writeJSON(path, json) {
-    const content = JSON.stringify(json, null, 4);
-    return await writeFile(path, content);
-}
-
 async function patchManifest(platform, debug, watch, test) {
     const manifest = await readJSON(`${srcDir}/manifest.json`);
     const manifestPatch = platform === PLATFORM.CHROME ? {} : await readJSON(`${srcDir}/manifest-${platform}.json`);

tasks/deno.js

@@ -0,0 +1,47 @@
+import {readJSON, writeJSON} from './utils.js';
+import {resolve} from 'node:path';
+
+function resolvePath(path) {
+    return resolve(import.meta.url.replace('file:/', ''), '../../', path);
+}
+
+function createImports(dependencies) {
+    const imports = {};
+    for (const name in dependencies) {
+        imports[name] = `npm:${name}@${dependencies[name]}`;
+    }
+    return imports;
+}
+
+function createTasks(scripts) {
+    const tasks = {};
+    for (const name in scripts) {
+        const command = scripts[name];
+        tasks[name] = command
+            .replace('--max-old-space-size=3072', '')
+            .replace('node ', 'deno run -A ')
+            .replaceAll('npm run ', 'deno task ');
+    }
+    return tasks;
+}
+
+async function writeDenoJSON() {
+    const packageJSON = resolvePath('package.json');
+    const denoJSON = await resolvePath('deno.json');
+    const pkg = await readJSON(packageJSON);
+
+    if (pkg.dependencies) {
+        console.error('TODO: support dependencies key in createImports()');
+    }
+    const imports = createImports(pkg.devDependencies);
+
+    const tasks = createTasks(pkg.scripts);
+
+    writeJSON(denoJSON, {imports, tasks});
+}
+
+async function main() {
+    await writeDenoJSON();
+}
+
+main();

tasks/log.js

@@ -1,4 +1,5 @@
 import {createWriteStream} from 'node:fs';
+import process from 'node:process';
 import {WebSocketServer} from 'ws';
 import {createTask} from './task.js';
 import {log} from './utils.js';

tasks/reload.js

@@ -1,3 +1,4 @@
+import process from 'node:process';
 import {WebSocketServer} from 'ws';
 import {log} from './utils.js';
 

tasks/utils.js

@@ -92,6 +92,25 @@ export async function writeFile(dest, content) {
     await fs.writeFile(dest, content, 'utf8');
 }
 
+/**
+ * @param {string} path
+ * @returns {Promise<Object>}
+ */
+export async function readJSON(path) {
+    const file = await readFile(path);
+    return JSON.parse(file);
+}
+
+/**
+ * @param {string} dest
+ * @param {string} content
+ * @returns {Promise<void>}
+ */
+export async function writeJSON(dest, content) {
+    const string = JSON.stringify(content, null, 4);
+    return await writeFile(dest, string);
+}
+
 /**
  * @param {string | string[]} patterns
  * @returns {Promise<string[]>}