Make babel-node a standalone package (#6023)

* Make babel-node a standalone package

* New package `babel-node` previously `babel-cli/bin/babel-node`

* updates

.gitignore

@@ -23,6 +23,7 @@ package-lock.json
 !/packages/babel-runtime/helpers/es6/toArray.js
 /packages/babel-register/test/.babel
 /packages/babel-cli/test/tmp
+/packages/babel-node/test/tmp
 /packages/*/lib
 .nyc_output
 /babel.sublime-workspace

packages/babel-node/.npmignore

@@ -0,0 +1,3 @@
+src
+test
+node_modules

packages/babel-node/README.md

@@ -0,0 +1,17 @@
+# babel-node
+
+> A Babel-powered Node.js CLI
+
+babel-node is a CLI that works exactly the same as the Node.js CLI, with the added benefit of compiling with Babel presets and plugins before running it.
+
+## Install
+
+```sh
+npm install --save-dev babel-node
+```
+
+## Usage
+
+```sh
+babel-node [options] [ -e script | script.js ] [arguments]
+```

packages/babel-node/bin/babel-node.js

@@ -0,0 +1,3 @@
+#!/usr/bin/env node
+
+require("../lib/babel-node");

packages/babel-node/package.json

@@ -0,0 +1,34 @@
+{
+  "name": "babel-node",
+  "version": "7.0.0-alpha.17",
+  "description": "Babel command line",
+  "author": "Sebastian McKenzie <sebmck@gmail.com>",
+  "homepage": "https://babeljs.io/",
+  "license": "MIT",
+  "repository": "https://github.com/babel/babel/tree/master/packages/babel-node",
+  "keywords": [
+    "6to5",
+    "babel",
+    "es6",
+    "transpile",
+    "transpiler",
+    "babel-cli",
+    "compiler"
+  ],
+  "dependencies": {
+    "babel-core": "7.0.0-alpha.17",
+    "babel-register": "7.0.0-alpha.17",
+    "babel-polyfill": "7.0.0-alpha.17",
+    "commander": "^2.8.1",
+    "fs-readdir-recursive": "^1.0.0",
+    "lodash": "^4.2.0",
+    "output-file-sync": "^2.0.0",
+    "v8flags": "^3.0.0"
+  },
+  "devDependencies": {
+    "babel-helper-fixtures": "7.0.0-alpha.17"
+  },
+  "bin": {
+    "babel-node": "./bin/babel-node.js"
+  }
+}

packages/babel-node/src/_babel-node.js

@@ -0,0 +1,186 @@
+import commander from "commander";
+import Module from "module";
+import { inspect } from "util";
+import path from "path";
+import repl from "repl";
+import * as babel from "babel-core";
+import vm from "vm";
+import "babel-polyfill";
+import register from "babel-register";
+
+import pkg from "../package.json";
+
+const program = new commander.Command("babel-node");
+
+function collect(value, previousValue): Array<string> {
+  // If the user passed the option with no value, like "babel-node file.js --presets", do nothing.
+  if (typeof value !== "string") return previousValue;
+
+  const values = value.split(",");
+
+  return previousValue ? previousValue.concat(values) : values;
+}
+
+/* eslint-disable max-len */
+program.option("-e, --eval [script]", "Evaluate script");
+program.option("-p, --print [code]", "Evaluate script and print result");
+program.option(
+  "-o, --only [globs]",
+  "A comma-separated list of glob patterns to compile",
+  collect,
+);
+program.option(
+  "-i, --ignore [globs]",
+  "A comma-separated list of glob patterns to skip compiling",
+  collect,
+);
+program.option(
+  "-x, --extensions [extensions]",
+  "List of extensions to hook into [.es6,.js,.es,.jsx,.mjs]",
+  collect,
+);
+program.option("-w, --plugins [string]", "", collect);
+program.option("-b, --presets [string]", "", collect);
+/* eslint-enable max-len */
+
+program.version(pkg.version);
+program.usage("[options] [ -e script | script.js ] [arguments]");
+program.parse(process.argv);
+
+register({
+  extensions: program.extensions,
+  ignore: program.ignore,
+  only: program.only,
+  plugins: program.plugins,
+  presets: program.presets,
+});
+
+const replPlugin = ({ types: t }) => ({
+  visitor: {
+    ModuleDeclaration(path) {
+      throw path.buildCodeFrameError("Modules aren't supported in the REPL");
+    },
+
+    VariableDeclaration(path) {
+      if (path.node.kind !== "var") {
+        throw path.buildCodeFrameError(
+          "Only `var` variables are supported in the REPL",
+        );
+      }
+    },
+
+    Program(path) {
+      if (path.get("body").some(child => child.isExpressionStatement())) return;
+
+      // If the executed code doesn't evaluate to a value,
+      // prevent implicit strict mode from printing 'use strict'.
+      path.pushContainer(
+        "body",
+        t.expressionStatement(t.identifier("undefined")),
+      );
+    },
+  },
+});
+
+const _eval = function(code, filename) {
+  code = code.trim();
+  if (!code) return undefined;
+
+  code = babel.transform(code, {
+    filename: filename,
+    presets: program.presets,
+    plugins: (program.plugins || []).concat([replPlugin]),
+  }).code;
+
+  return vm.runInThisContext(code, {
+    filename: filename,
+  });
+};
+
+if (program.eval || program.print) {
+  let code = program.eval;
+  if (!code || code === true) code = program.print;
+
+  global.__filename = "[eval]";
+  global.__dirname = process.cwd();
+
+  const module = new Module(global.__filename);
+  module.filename = global.__filename;
+  module.paths = Module._nodeModulePaths(global.__dirname);
+
+  global.exports = module.exports;
+  global.module = module;
+  global.require = module.require.bind(module);
+
+  const result = _eval(code, global.__filename);
+  if (program.print) {
+    const output = typeof result === "string" ? result : inspect(result);
+    process.stdout.write(output + "\n");
+  }
+} else {
+  if (program.args.length) {
+    // slice all arguments up to the first filename since they're babel args that we handle
+    let args = process.argv.slice(2);
+
+    let i = 0;
+    let ignoreNext = false;
+    args.some(function(arg, i2) {
+      if (ignoreNext) {
+        ignoreNext = false;
+        return;
+      }
+
+      if (arg[0] === "-") {
+        const parsedArg = program[arg.slice(2)];
+        if (parsedArg && parsedArg !== true) {
+          ignoreNext = true;
+        }
+      } else {
+        i = i2;
+        return true;
+      }
+    });
+    args = args.slice(i);
+
+    // make the filename absolute
+    const filename = args[0];
+    if (!path.isAbsolute(filename)) {
+      args[0] = path.join(process.cwd(), filename);
+    }
+
+    // add back on node and concat the sliced args
+    process.argv = ["node"].concat(args);
+    process.execArgv.unshift(__filename);
+
+    Module.runMain();
+  } else {
+    replStart();
+  }
+}
+
+function replStart() {
+  repl.start({
+    prompt: "> ",
+    input: process.stdin,
+    output: process.stdout,
+    eval: replEval,
+    useGlobal: true,
+  });
+}
+
+function replEval(code, context, filename, callback) {
+  let err;
+  let result;
+
+  try {
+    if (code[0] === "(" && code[code.length - 1] === ")") {
+      code = code.slice(1, -1); // remove "(" and ")"
+    }
+
+    result = _eval(code, filename);
+  } catch (e) {
+    err = e;
+  }
+
+  callback(err, result);
+}

packages/babel-node/src/babel-node.js

@@ -0,0 +1,98 @@
+/**
+ * This tiny wrapper file checks for known node flags and appends them
+ * when found, before invoking the "real" _babel-node(1) executable.
+ */
+
+import getV8Flags from "v8flags";
+import path from "path";
+
+let args = [path.join(__dirname, "_babel-node")];
+
+let babelArgs = process.argv.slice(2);
+let userArgs;
+
+// separate node arguments from script arguments
+const argSeparator = babelArgs.indexOf("--");
+if (argSeparator > -1) {
+  userArgs = babelArgs.slice(argSeparator); // including the  --
+  babelArgs = babelArgs.slice(0, argSeparator);
+}
+
+/**
+ * Replace dashes with underscores in the v8Flag name
+ * Also ensure that if the arg contains a value (e.g. --arg=true)
+ * that only the flag is returned.
+ */
+function getNormalizedV8Flag(arg) {
+  const matches = arg.match(/--(.+)/);
+
+  if (matches) {
+    return `--${matches[1].replace(/-/g, "_")}`;
+  }
+
+  return arg;
+}
+
+getV8Flags(function(err, v8Flags) {
+  babelArgs.forEach(function(arg) {
+    const flag = arg.split("=")[0];
+
+    switch (flag) {
+      case "-d":
+        args.unshift("--debug");
+        break;
+
+      case "debug":
+      case "--debug":
+      case "--debug-brk":
+      case "--inspect":
+        args.unshift(arg);
+        break;
+
+      case "-gc":
+        args.unshift("--expose-gc");
+        break;
+
+      case "--nolazy":
+        args.unshift(flag);
+        break;
+
+      default:
+        if (
+          v8Flags.indexOf(getNormalizedV8Flag(flag)) >= 0 ||
+          arg.indexOf("--trace") === 0
+        ) {
+          args.unshift(arg);
+        } else {
+          args.push(arg);
+        }
+        break;
+    }
+  });
+
+  // append arguments passed after --
+  if (argSeparator > -1) {
+    args = args.concat(userArgs);
+  }
+
+  try {
+    const kexec = require("kexec");
+    kexec(process.argv[0], args);
+  } catch (err) {
+    if (err.code !== "MODULE_NOT_FOUND") throw err;
+
+    const child_process = require("child_process");
+    const proc = child_process.spawn(process.argv[0], args, {
+      stdio: "inherit",
+    });
+    proc.on("exit", function(code, signal) {
+      process.on("exit", function() {
+        if (signal) {
+          process.kill(process.pid, signal);
+        } else {
+          process.exit(code);
+        }
+      });
+    });
+  }
+});

packages/babel-node/test/fixtures/babel-node/--eval/options.json

@@ -0,0 +1,4 @@
+{
+  "args": ["--eval", "console.log([1, 2, 3].map(x => x * x));"],
+  "stdout": "[ 1, 4, 9 ]"
+}

packages/babel-node/test/fixtures/babel-node/--extensions/in-files/foo.bar

@@ -0,0 +1 @@
+console.log([1, 2, 3].map(x => x * x));

packages/babel-node/test/fixtures/babel-node/--extensions/options.json

@@ -0,0 +1,4 @@
+{
+  "args": ["foo", "--extensions", ".bar"],
+  "stdout": "[ 1, 4, 9 ]"
+}

packages/babel-node/test/fixtures/babel-node/--print/options.json

@@ -0,0 +1,4 @@
+{
+  "args": ["--print", "--eval", "([1, 2, 3].map(x => x * x))"],
+  "stdout": "[ 1, 4, 9 ]"
+}

packages/babel-node/test/fixtures/babel-node/arguments/in-files/bar.js

@@ -0,0 +1 @@
+console.log(process.argv[2]);

packages/babel-node/test/fixtures/babel-node/arguments/options.json

@@ -0,0 +1,4 @@
+{
+  "args": ["bar", "foo"],
+  "stdout": "foo"
+}

packages/babel-node/test/fixtures/babel-node/directory/in-files/foo/index.js

@@ -0,0 +1,2 @@
+var foo = () => console.log("foo");
+foo();

packages/babel-node/test/fixtures/babel-node/directory/options.json

@@ -0,0 +1,3 @@
+{
+  "args": ["foo"]
+}

packages/babel-node/test/fixtures/babel-node/directory/stdout.txt

@@ -0,0 +1 @@
+foo

packages/babel-node/test/fixtures/babel-node/filename/in-files/bar.js

@@ -0,0 +1,2 @@
+var foo = () => console.log("foo");
+foo();

packages/babel-node/test/fixtures/babel-node/filename/options.json

@@ -0,0 +1,3 @@
+{
+  "args": ["bar"]
+}

packages/babel-node/test/fixtures/babel-node/filename/stdout.txt

@@ -0,0 +1 @@
+foo