Add lua WASM command (#56)

README.md

@@ -4,6 +4,9 @@ In-browser bash-like shell implemented in a combination of TypeScript and WebAss
 
 Used in the [JupyterLite terminal extension](https://github.com/jupyterlite/terminal).
 
+This is an early-stage work in progress and should be considered experimental code. Anything and
+everything could change at any time.
+
 The commands used here are either built-in commands implemented in TypeScript, or WebAssembly
 commands compiled into .js and .wasm files. The latter are built by
 [Emscripten-forge](https://emscripten-forge.org/) and are added to the `cockle` NPM package using

demo/serve/demo.ts

@@ -28,7 +28,16 @@ export class Demo {
         'file.txt': 'This is the contents of the file',
         'other.txt': 'Some other file\nSecond line',
         'months.txt':
-          'January\nFebruary\nMarch\nApril\nMay\nJune\nJuly\nAugust\nSeptember\nOctober\nNovember\nDecember\n'
+          'January\nFebruary\nMarch\nApril\nMay\nJune\nJuly\nAugust\nSeptember\nOctober\nNovember\nDecember\n',
+        'factorial.lua':
+          'function factorial(n)\n' +
+          '  if n == 0 then\n' +
+          '    return 1\n' +
+          '  else\n' +
+          '    return n * factorial(n-1)\n' +
+          '  end\n' +
+          'end\n' +
+          'print(factorial(tonumber(arg[1])))\n'
       }
     });
   }

package.json

@@ -19,7 +19,7 @@
     "main": "lib/index.js",
     "types": "lib/index.d.ts",
     "scripts": {
-        "fetch:wasm:create-env": "micromamba create -p $(pwd)/cockle_wasm_env -y cockle_fs grep coreutils --platform=emscripten-wasm32 -c https://repo.mamba.pm/emscripten-forge -c https://repo.mamba.pm/conda-forge",
+        "fetch:wasm:create-env": "micromamba create -p $(pwd)/cockle_wasm_env -y cockle_fs grep coreutils lua --platform=emscripten-wasm32 -c https://repo.mamba.pm/emscripten-forge -c https://repo.mamba.pm/conda-forge",
         "fetch:wasm:copy": "mkdir -p src/wasm && cp $(pwd)/cockle_wasm_env/bin/*.js src/wasm/ && cp $(pwd)/cockle_wasm_env/bin/*.wasm src/wasm/",
         "fetch:wasm": "npm run fetch:wasm:create-env && npm run fetch:wasm:copy",
         "build": "tsc && cp src/wasm/*.wasm lib/wasm/",

src/command_registry.ts

@@ -1,6 +1,7 @@
 import { ICommandRunner } from './commands/command_runner';
 import { CoreutilsCommandRunner } from './commands/coreutils_command_runner';
 import { GrepCommandRunner } from './commands/grep_command_runner';
+import { LuaCommandRunner } from './commands/lua_command_runner';
 import * as AllBuiltinCommands from './builtin';
 import { WasmLoader } from './wasm_loader';
 
@@ -10,7 +11,8 @@ export class CommandRegistry {
 
     this._commandRunners = [
       new CoreutilsCommandRunner(wasmLoader),
-      new GrepCommandRunner(wasmLoader)
+      new GrepCommandRunner(wasmLoader),
+      new LuaCommandRunner(wasmLoader)
     ];
 
     // Command name -> runner mapping

src/commands/lua_command_runner.ts

@@ -0,0 +1,16 @@
+import { WasmCommandRunner } from './wasm_command_runner';
+import { WasmLoader } from '../wasm_loader';
+
+export class LuaCommandRunner extends WasmCommandRunner {
+  constructor(wasmLoader: WasmLoader) {
+    super(wasmLoader);
+  }
+
+  moduleName(): string {
+    return 'lua';
+  }
+
+  names(): string[] {
+    return ['lua'];
+  }
+}

test/tests/command/lua.test.ts

@@ -0,0 +1,33 @@
+import { expect } from '@playwright/test';
+import { shellLineSimple, shellLineSimpleN, test } from '../utils';
+
+test.describe('lua command', () => {
+  test('should write to stdout', async ({ page }) => {
+    const output = await shellLineSimple(page, 'lua -v');
+    expect(output).toMatch('Lua 5.4.6  Copyright (C) 1994-2023 Lua.org, PUC-Rio');
+  });
+
+  test('should run lua script', async ({ page }) => {
+    const options = {
+      initialFiles: {
+        'factorial.lua':
+          'function factorial(n)\n' +
+          '  if n == 0 then\n' +
+          '    return 1\n' +
+          '  else\n' +
+          '    return n * factorial(n-1)\n' +
+          '  end\n' +
+          'end\n' +
+          'print(factorial(tonumber(arg[1])))\n'
+      }
+    };
+    const output = await shellLineSimpleN(
+      page,
+      ['lua factorial.lua 1', 'lua factorial.lua 3', 'lua factorial.lua 5'],
+      options
+    );
+    expect(output[0]).toMatch(/^lua factorial.lua 1\r\n1\r\n/);
+    expect(output[1]).toMatch(/^lua factorial.lua 3\r\n6\r\n/);
+    expect(output[2]).toMatch(/^lua factorial.lua 5\r\n120\r\n/);
+  });
+});