timers: add v0.4 compatibility hack

If a timer callback throws and the user's uncaughtException handler ignores the
exception, other timers that expire on the current tick should still run.

If #2582 goes through, this hack should be removed.

Fixes #2631.

lib/timers.js

@@ -81,7 +81,21 @@ function insert(item, msecs) {
         } else {
           L.remove(first);
           assert(first !== L.peek(list));
-          if (first._onTimeout) first._onTimeout();
+
+          if (!first._onTimeout) continue;
+
+          // v0.4 compatibility: if the timer callback throws and the user's
+          // uncaughtException handler ignores the exception, other timers that
+          // expire on this tick should still run. If #2582 goes through, this
+          // hack should be removed.
+          //
+          // https://github.com/joyent/node/issues/2631
+          try {
+            first._onTimeout();
+          } catch (e) {
+            if (!process.listeners('uncaughtException').length) throw e;
+            process.emit('uncaughtException', e);
+          }
         }
       }
 

test/simple/test-timers-uncaught-exception.js

@@ -0,0 +1,52 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+var common = require('../common');
+var assert = require('assert');
+
+var exceptions = 0;
+var timer1 = 0;
+var timer2 = 0;
+
+// the first timer throws...
+setTimeout(function() {
+  timer1++;
+  throw new Error('BAM!');
+}, 100);
+
+// ...but the second one should still run
+setTimeout(function() {
+  assert.equal(timer1, 1);
+  timer2++;
+}, 100);
+
+function uncaughtException(err) {
+  assert.equal(err.message, 'BAM!');
+  exceptions++;
+}
+process.on('uncaughtException', uncaughtException);
+
+process.on('exit', function() {
+  process.removeListener('uncaughtException', uncaughtException);
+  assert.equal(exceptions, 1);
+  assert.equal(timer1, 1);
+  assert.equal(timer2, 1);
+});