Allow to load modules in non strict mode

README.md

@@ -144,6 +144,8 @@ Unlike `VM`, `NodeVM` allows you to require modules in the same way that you wou
 * `require.context` - `host` (default) to require modules in the host and proxy them into the sandbox. `sandbox` to load, compile, and require modules in the sandbox. Except for `events`, built-in modules are always required in the host and proxied into the sandbox.
 * `require.import` - An array of modules to be loaded into NodeVM on start.
 * `require.resolve` - An additional lookup function in case a module wasn't found in one of the traditional node lookup paths.
+* `require.customRequire` - Use instead of the `require` function to load modules from the host.
+* `require.strict` - `false` to disable loading modules in strict mode (default: `true`).
 * `nesting` - **WARNING**: Allowing this is a security risk as scripts can create a NodeVM which can require any host module. `true` to enable VMs nesting (default: `false`).
 * `wrapper` - `commonjs` (default) to wrap script into CommonJS wrapper, `none` to retrieve value returned by the script.
 * `argv` - Array to be passed to `process.argv`.

index.d.ts

@@ -24,6 +24,8 @@ export interface VMRequire {
   resolve?: (moduleName: string, parentDirname: string) => string | undefined;
   /** Custom require to require host and built-in modules. */
   customRequire?: (id: string) => any;
+  /** Load modules in strict mode. (default: true) */
+  strict?: boolean;
 }
 
 /**

lib/nodevm.js

@@ -184,6 +184,7 @@ class NodeVM extends VM {
 	 * @param {resolveCallback} [options.require.resolve] - An additional lookup function in case a module wasn't
 	 * found in one of the traditional node lookup paths.
 	 * @param {customRequire} [options.require.customRequire=require] - Custom require to require host and built-in modules.
+	 * @param {boolean} [option.require.strict=true] - Load required modules in strict mode.
 	 * @param {boolean} [options.nesting=false] -
 	 * <b>WARNING: Allowing this is a security risk as scripts can create a NodeVM which can require any host module.</b>
 	 * Allow nesting of VMs.

lib/resolver-compat.js

@@ -46,8 +46,8 @@ function makeExternalMatcher(obj) {
 
 class LegacyResolver extends DefaultResolver {
 
-	constructor(builtinModules, checkPath, globalPaths, pathContext, customResolver, hostRequire, compiler, externals, allowTransitive) {
-		super(builtinModules, checkPath, globalPaths, pathContext, customResolver, hostRequire, compiler);
+	constructor(builtinModules, checkPath, globalPaths, pathContext, customResolver, hostRequire, compiler, strict, externals, allowTransitive) {
+		super(builtinModules, checkPath, globalPaths, pathContext, customResolver, hostRequire, compiler, strict);
 		this.externals = externals;
 		this.currMod = undefined;
 		this.trustedMods = new WeakMap();
@@ -282,7 +282,8 @@ function resolverFromOptions(vm, options, override, compiler) {
 		root: rootPaths,
 		resolve: customResolver,
 		customRequire: hostRequire = defaultRequire,
-		context = 'host'
+		context = 'host',
+		strict = true,
 	} = options;
 
 	const builtins = genBuiltinsFromOptions(vm, builtinOpt, mockOpt, override);
@@ -325,7 +326,7 @@ function resolverFromOptions(vm, options, override, compiler) {
 	}
 
 	if (typeof externalOpt !== 'object') {
-		return new DefaultResolver(builtins, checkPath, [], () => context, newCustomResolver, hostRequire, compiler);
+		return new DefaultResolver(builtins, checkPath, [], () => context, newCustomResolver, hostRequire, compiler, strict);
 	}
 
 	let transitive = false;
@@ -336,7 +337,7 @@ function resolverFromOptions(vm, options, override, compiler) {
 		transitive = context === 'sandbox' && externalOpt.transitive;
 	}
 	externals = external.map(makeExternalMatcher);
-	return new LegacyResolver(builtins, checkPath, [], () => context, newCustomResolver, hostRequire, compiler, externals, transitive);
+	return new LegacyResolver(builtins, checkPath, [], () => context, newCustomResolver, hostRequire, compiler, strict, externals, transitive);
 }
 
 exports.resolverFromOptions = resolverFromOptions;

lib/resolver.js

@@ -140,12 +140,13 @@ class Resolver {
 
 class DefaultResolver extends Resolver {
 
-	constructor(builtinModules, checkPath, globalPaths, pathContext, customResolver, hostRequire, compiler) {
+	constructor(builtinModules, checkPath, globalPaths, pathContext, customResolver, hostRequire, compiler, strict) {
 		super(builtinModules, globalPaths, hostRequire);
 		this.checkPath = checkPath;
 		this.pathContext = pathContext;
 		this.customResolver = customResolver;
 		this.compiler = compiler;
+		this.strict = strict;
 		this.packageCache = {__proto__: null};
 		this.scriptCache = {__proto__: null};
 	}
@@ -200,7 +201,7 @@ class DefaultResolver extends Resolver {
 		this.checkAccess(mod, filename);
 		if (this.pathContext(filename, 'js') === 'sandbox') {
 			const script = this.readScript(filename);
-			vm.run(script, {filename, strict: true, module: mod, wrapper: 'none', dirname: mod.path});
+			vm.run(script, {filename, strict: this.strict, module: mod, wrapper: 'none', dirname: mod.path});
 		} else {
 			const m = this.hostRequire(filename);
 			mod.exports = vm.readonly(m);