/**

* 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";

// TODO: When support for node < 10.10 will be dropped, this package

// can be replaced with process.allowedNodeEnvironmentFlags

import allowedNodeEnvironmentFlags from "node-environment-flags";

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) {

// v8 uses the "no" prefix to negate boolean flags (e.g. --nolazy),

// but they are not listed by v8flags

const matches = arg.match(/--(?:no)?(.+)/);

if (matches) {

return `--${matches[1].replace(/-/g, "_")}`;

}

return arg;

}

// These are aliases for node options defined by babel-node.

const aliases = new Map([

["-d", "--debug"],

["-gc", "--expose-gc"],

]);

getV8Flags(function (err, v8Flags) {

for (let i = 0; i < babelArgs.length; i++) {

const arg = babelArgs[i];

const flag = arg.split("=")[0];

if (flag === "-r" || flag === "--require") {

args.push(flag);

args.push(babelArgs[++i]);

} else if (aliases.has(flag)) {

args.unshift(aliases.get(flag));

} else if (

flag === "debug" || // node debug foo.js

flag === "inspect" ||

v8Flags.indexOf(getNormalizedV8Flag(flag)) >= 0 ||

allowedNodeEnvironmentFlags.has(flag)

) {

args.unshift(arg);

} else {

args.push(arg);

}

}

// 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" &&

err.code !== "UNDECLARED_DEPENDENCY"

) {

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.exitCode = code;

}

});

});

process.on("SIGINT", () => proc.kill("SIGINT"));

}

});