vm: don't abort process when stack space runs out

Make less assumptions about what objects will be available when vm context creation or error message printing fail because V8 runs out of JS stack space. Ref: #6899 PR-URL: #6907 Reviewed-By: Ben Noordhuis <[email protected]>

Author: addaleax

src/node_contextify.cc

@@ -205,7 +205,11 @@ class ContextifyContext{
 
  Local<Context> ctx = Context::New(env->isolate(), nullptr, object_template);
 
-CHECK(!ctx.IsEmpty());
+if (ctx.IsEmpty()){
+ env->ThrowError("Could not instantiate context");
+return Local<Context>();
+ }
+
  ctx->SetSecurityToken(env->context()->GetSecurityToken());
 
 // We need to tie the lifetime of the sandbox object with the lifetime of

test/parallel/test-vm-low-stack-space.js

@@ -0,0 +1,26 @@
+'use strict';
+require('../common');
+constassert=require('assert');
+constvm=require('vm');
+
+functiona(){
+try{
+returna();
+}catch(e){
+// Throw an exception as near to the recursion-based RangeError as possible.
+returnvm.runInThisContext('() => 42')();
+}
+}
+
+assert.strictEqual(a(),42);
+
+functionb(){
+try{
+returnb();
+}catch(e){
+// This writes a lot of noise to stderr, but it still works.
+returnvm.runInNewContext('() => 42')();
+}
+}
+
+assert.strictEqual(b(),42);