domain: Fix double-exit on nested domains

Minor oversight in fix for #4953.

src/node.js

@@ -258,7 +258,9 @@
           // The domain error handler threw!  oh no!
           // See if another domain can catch THIS error,
           // or else crash on the original one.
-          domainStack.pop();
+          // If the user already exited it, then don't double-exit.
+          if (domain === domainModule.active)
+            domainStack.pop();
           if (domainStack.length) {
             var parentDomain = domainStack[domainStack.length - 1];
             process.domain = domainModule.active = parentDomain;

test/simple/test-domain-nested-throw.js

@@ -24,6 +24,34 @@ var assert = require('assert');
 
 var domain = require('domain');
 
+var dispose;
+switch (process.argv[2]) {
+  case 'true':
+    dispose = true;
+    break;
+  case 'false':
+    dispose = false;
+    break;
+  default:
+    parent();
+    return;
+}
+
+function parent() {
+  var node = process.execPath;
+  var spawn = require('child_process').spawn;
+  var opt = { stdio: 'inherit' };
+  var child = spawn(node, [__filename, 'true'], opt);
+  child.on('exit', function(c) {
+    assert(!c);
+    child = spawn(node, [__filename, 'false'], opt);
+    child.on('exit', function(c) {
+      assert(!c);
+      console.log('ok');
+    });
+  });
+}
+
 var gotDomain1Error = false;
 var gotDomain2Error = false;
 
@@ -44,8 +72,11 @@ function inner(throw1, throw2) {
   var domain1 = domain.createDomain();
 
   domain1.on('error', function (err) {
-    console.error('domain 1 error');
-    if (gotDomain1Error) process.exit(1);
+    if (gotDomain1Error) {
+      console.error('got domain 1 twice');
+      process.exit(1);
+    }
+    if (dispose) domain1.dispose();
     gotDomain1Error = true;
     throw2();
   });
@@ -59,7 +90,10 @@ function outer() {
   var domain2 = domain.createDomain();
 
   domain2.on('error', function (err) {
-    console.error('domain 2 error');
+    if (gotDomain2Error) {
+      console.error('got domain 2 twice');
+      process.exit(1);
+    }
     gotDomain2Error = true;
   });
 
@@ -73,7 +107,7 @@ process.on('exit', function() {
   assert(gotDomain2Error);
   assert(threw1);
   assert(threw2);
-  console.log('ok');
+  console.log('ok', dispose);
 });
 
 outer();