From 6f89fe04ea4797627730d9e514c49b83e4580e9d Mon Sep 17 00:00:00 2001
From: Patrick Steele-Idem <pnidem@gmail.com>
Date: Wed, 12 Apr 2017 20:27:59 -0600
Subject: [PATCH] Refactored out nextTick/setImmediate for better error
 handling

---
 components/update-manager.js | 31 +++----------------------------
 runtime/nextTick-browser.js  | 30 ++++++++++++++++++++++++++++++
 runtime/nextTick.js          |  1 +
 runtime/package.json         |  3 ++-
 taglibs/async/await-tag.js   | 36 +++++++++++++++++++-----------------
 5 files changed, 55 insertions(+), 46 deletions(-)
 create mode 100644 runtime/nextTick-browser.js
 create mode 100644 runtime/nextTick.js

diff --git a/components/update-manager.js b/components/update-manager.js
index 8bc1285e3..391f1e028 100644
--- a/components/update-manager.js
+++ b/components/update-manager.js
@@ -4,32 +4,7 @@ var updatesScheduled = false;
 var batchStack = []; // A stack of batched updates
 var unbatchedQueue = []; // Used for scheduled batched updates
 
-var win = window;
-var setImmediate = win.setImmediate;
-
-if (!setImmediate) {
-    if (win.postMessage) {
-        var queue = [];
-        var messageName = 'si';
-        win.addEventListener('message', function (event) {
-            var source = event.source;
-            if (source == win || !source && event.data === messageName) {
-                event.stopPropagation();
-                if (queue.length > 0) {
-                    var fn = queue.shift();
-                    fn();
-                }
-            }
-        }, true);
-
-        setImmediate = function(fn) {
-            queue.push(fn);
-            win.postMessage(messageName, '*');
-        };
-    } else {
-        setImmediate = setTimeout;
-    }
-}
+var nextTick = require('../runtime/nextTick');
 
 /**
  * This function is called when we schedule the update of "unbatched"
@@ -57,7 +32,7 @@ function scheduleUpdates() {
 
     updatesScheduled = true;
 
-    setImmediate(updateUnbatchedComponents);
+    nextTick(updateUnbatchedComponents);
 }
 
 function updateComponents(queue) {
@@ -129,4 +104,4 @@ function queueComponentUpdate(component) {
 }
 
 exports.$__queueComponentUpdate = queueComponentUpdate;
-exports.$__batchUpdate = batchUpdate;
\ No newline at end of file
+exports.$__batchUpdate = batchUpdate;
diff --git a/runtime/nextTick-browser.js b/runtime/nextTick-browser.js
new file mode 100644
index 000000000..0582c87ea
--- /dev/null
+++ b/runtime/nextTick-browser.js
@@ -0,0 +1,30 @@
+/* globals window */
+
+var win = window;
+var setImmediate = win.setImmediate;
+
+if (!setImmediate) {
+    if (win.postMessage) {
+        var queue = [];
+        var messageName = 'si';
+        win.addEventListener('message', function (event) {
+            var source = event.source;
+            if (source == win || !source && event.data === messageName) {
+                event.stopPropagation();
+                if (queue.length > 0) {
+                    var fn = queue.shift();
+                    fn();
+                }
+            }
+        }, true);
+
+        setImmediate = function(fn) {
+            queue.push(fn);
+            win.postMessage(messageName, '*');
+        };
+    } else {
+        setImmediate = setTimeout;
+    }
+}
+
+module.exports = setImmediate;
diff --git a/runtime/nextTick.js b/runtime/nextTick.js
new file mode 100644
index 000000000..51f167c98
--- /dev/null
+++ b/runtime/nextTick.js
@@ -0,0 +1 @@
+module.exports = process.nextTick;
diff --git a/runtime/package.json b/runtime/package.json
index 7614baa1b..e90efdcc0 100644
--- a/runtime/package.json
+++ b/runtime/package.json
@@ -1,6 +1,7 @@
 {
     "browser": {
         "./loader/index.js": "./loader/index-browser.js",
+        "./nextTick": "./nextTick-browser.js",
         "./env-init.js": false
     }
-}
\ No newline at end of file
+}
diff --git a/taglibs/async/await-tag.js b/taglibs/async/await-tag.js
index ab49c3f64..2ff3765e6 100644
--- a/taglibs/async/await-tag.js
+++ b/taglibs/async/await-tag.js
@@ -3,32 +3,30 @@
 var logger = require('raptor-logging').logger(module);
 var AsyncValue = require('raptor-async/AsyncValue');
 var isClientReorderSupported = require('./client-reorder').isSupported;
+var nextTick = require('../../runtime/nextTick');
 
 function isPromise(o) {
     return o && typeof o.then === 'function';
 }
 
+function safeRenderBody(renderBody, targetOut, data) {
+    try {
+        renderBody(targetOut, data);
+    } catch(err) {
+        return err;
+    }
+}
+
 function promiseToCallback(promise, callback, thisObj) {
     if (callback) {
         var finalPromise = promise
             .then(function(data) {
-                callback(null, data);
+                nextTick(callback.bind(this, null, data));
+            })
+            .then(null, function(err) {
+                nextTick(callback.bind(this, err));
             });
 
-        if (typeof promise.catch === 'function') {
-            finalPromise = finalPromise.catch(function(err) {
-                callback(err);
-            });
-        } else if (typeof promise.fail === 'function') {
-            finalPromise = finalPromise.fail(function(err) {
-                callback(err);
-            });
-        } else {
-            finalPromise = finalPromise.then(null, function(err) {
-                callback(err);
-            });
-        }
-
         if (finalPromise.done) {
             finalPromise.done();
         }
@@ -116,8 +114,12 @@ module.exports = function awaitTag(input, out) {
         } else if (renderTimeout) {
             renderTimeout(targetOut);
         } else {
-            if (input.renderBody) {
-                input.renderBody(targetOut, data);
+            var renderBodyFunc = input.renderBody;
+            if (renderBodyFunc) {
+                var renderBodyErr = safeRenderBody(renderBodyFunc, targetOut, data);
+                if (renderBodyErr) {
+                    return renderBody(renderBodyErr);
+                }
             }
         }