feat: add unhandledRejectionHandler (#3)

Removes handling of rejected promises from the unhandled
exception handler and adds an unhandled rejection handler
to replace the functionality. This allows users to distinguish
between the two situations.

BREAKING CHANGE: unhandledExceptionHandler no longer
catches rejections.

index.js

@@ -149,6 +149,14 @@ add.uncaughtExceptionHandler = function (hook) {
 
 	if (errHooks.length === 1) {
 		process.once('uncaughtException', exit.bind(null, true, 1));
+	}
+};
+
+// Add an unhandled rejection handler
+add.unhandledRejectionHandler = function (hook) {
+	errHooks.push(hook);
+
+	if (errHooks.length === 1) {
 		process.once('unhandledRejection', exit.bind(null, true, 1));
 	}
 };

readme.md

@@ -67,6 +67,11 @@ exitHook.uncaughtExceptionHandler(err => {
     console.error(err);
 });
 
+// You can hook unhandled rejections with unhandledRejectionHandler()
+exitHook.unhandledRejectionHandler(err => {
+    console.error(err);
+});
+
 // You can add multiple uncaught error handlers
 // Add the second parameter (callback) to indicate async hooks
 exitHook.uncaughtExceptionHandler((err, callback) => {

test/cases/unhandled-promise.js

@@ -14,13 +14,13 @@ exitHook(function () {
 	stub.called();
 });
 
-exitHook.uncaughtExceptionHandler(function (err, cb) {
+exitHook.unhandledRejectionHandler(function (err, cb) {
 	setTimeout(function () {
 		stub.called();
 		cb();
 	}, 50);
 	if (!err || err.message !== 'test-promise') {
-		stub.reject(`No error passed to uncaughtExceptionHandler, or message not test-promise - ${err.message}`);
+		stub.reject(`No error passed to unhandledRejectionHandler, or message not test-promise - ${err.message}`);
 	}
 	stub.called();
 });