From af80f4765e2a9e795f64103b6e15770cf6eda050 Mon Sep 17 00:00:00 2001
From: Thomas Grainger <tom@procensus.com>
Date: Thu, 30 Mar 2017 09:42:29 +0100
Subject: [PATCH] provide isError and use it in place of instanceof Error

Fixes #15868
---
 src/.eslintrc.json          |  1 +
 src/Angular.js              | 23 +++++++++++++++++++++++
 src/ng/compile.js           |  2 +-
 src/ng/log.js               |  2 +-
 src/ng/q.js                 |  2 +-
 src/ngMock/angular-mocks.js |  2 +-
 test/.eslintrc.json         |  1 +
 test/minErrSpec.js          |  1 +
 test/ng/qSpec.js            |  2 +-
 9 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/src/.eslintrc.json b/src/.eslintrc.json
index 4c240b733bf9..3f8163dcc9af 100644
--- a/src/.eslintrc.json
+++ b/src/.eslintrc.json
@@ -50,6 +50,7 @@
     "isNumber": false,
     "isNumberNaN": false,
     "isDate": false,
+    "isError": false,
     "isArray": false,
     "isFunction": false,
     "isRegExp": false,
diff --git a/src/Angular.js b/src/Angular.js
index 7f539e81fb52..dcfb2fece29e 100644
--- a/src/Angular.js
+++ b/src/Angular.js
@@ -45,6 +45,7 @@
   isNumber,
   isNumberNaN,
   isDate,
+  isError,
   isArray,
   isFunction,
   isRegExp,
@@ -673,6 +674,28 @@ function isDate(value) {
  */
 var isArray = Array.isArray;
 
+/**
+ * @ngdoc function
+ * @name angular.isError
+ * @module ng
+ * @kind function
+ *
+ * @description
+ * Determines if a reference is an `Error`.
+ *
+ * @param {*} value Reference to check.
+ * @returns {boolean} True if `value` is an `Error`.
+ */
+function isError(value) {
+  var tag = ({}).toString.call(value);
+  switch (tag) {
+    case '[object Error]': return true;
+    case '[object Exception]': return true;
+    case '[object DOMException]': return true;
+    default: return value instanceof Error;
+  }
+}
+
 /**
  * @ngdoc function
  * @name angular.isFunction
diff --git a/src/ng/compile.js b/src/ng/compile.js
index 0405d3be76d3..a2d9730c3920 100644
--- a/src/ng/compile.js
+++ b/src/ng/compile.js
@@ -3098,7 +3098,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
           }
           linkQueue = null;
         }).catch(function(error) {
-          if (error instanceof Error) {
+          if (isError(error)) {
             $exceptionHandler(error);
           }
         });
diff --git a/src/ng/log.js b/src/ng/log.js
index 6849ed46de29..5dc36f23ae46 100644
--- a/src/ng/log.js
+++ b/src/ng/log.js
@@ -132,7 +132,7 @@ function $LogProvider() {
     };
 
     function formatError(arg) {
-      if (arg instanceof Error) {
+      if (isError(arg)) {
         if (arg.stack && formatStackTrace) {
           arg = (arg.message && arg.stack.indexOf(arg.message) === -1)
               ? 'Error: ' + arg.message + '\n' + arg.stack
diff --git a/src/ng/q.js b/src/ng/q.js
index 8aff2e0cfe21..03cb238cd7dd 100644
--- a/src/ng/q.js
+++ b/src/ng/q.js
@@ -381,7 +381,7 @@ function qFactory(nextTick, exceptionHandler, errorOnUnhandledRejections) {
       if (!toCheck.pur) {
         toCheck.pur = true;
         var errorMessage = 'Possibly unhandled rejection: ' + toDebugString(toCheck.value);
-        if (toCheck.value instanceof Error) {
+        if (isError(toCheck.value)) {
           exceptionHandler(toCheck.value, errorMessage);
         } else {
           exceptionHandler(errorMessage);
diff --git a/src/ngMock/angular-mocks.js b/src/ngMock/angular-mocks.js
index d6e84c75584f..3fcf3a31ea84 100644
--- a/src/ngMock/angular-mocks.js
+++ b/src/ngMock/angular-mocks.js
@@ -984,7 +984,7 @@ angular.mock.dump = function(object) {
     } else if (angular.isObject(object)) {
       if (angular.isFunction(object.$eval) && angular.isFunction(object.$apply)) {
         out = serializeScope(object);
-      } else if (object instanceof Error) {
+      } else if (angular.isError(object)) {
         out = object.stack || ('' + object.name + ': ' + object.message);
       } else {
         // TODO(i): this prevents methods being logged,
diff --git a/test/.eslintrc.json b/test/.eslintrc.json
index 007b458949ad..37a263e305f2 100644
--- a/test/.eslintrc.json
+++ b/test/.eslintrc.json
@@ -64,6 +64,7 @@
     "isNumber": false,
     "isNumberNaN": false,
     "isDate": false,
+    "isError": false,
     "isArray": false,
     "isFunction": false,
     "isRegExp": false,
diff --git a/test/minErrSpec.js b/test/minErrSpec.js
index 62f78c2c3ad1..633e795452a6 100644
--- a/test/minErrSpec.js
+++ b/test/minErrSpec.js
@@ -17,6 +17,7 @@ describe('minErr', function() {
   it('should return an Error factory', function() {
     var myError = testError('test', 'Oops');
     expect(myError instanceof Error).toBe(true);
+    expect(isError(myError)).toBe(true);
   });
 
   it('should generate stack trace at the frame where the minErr instance was called', function() {
diff --git a/test/ng/qSpec.js b/test/ng/qSpec.js
index f3a983100e41..23c939e689f4 100644
--- a/test/ng/qSpec.js
+++ b/test/ng/qSpec.js
@@ -37,7 +37,7 @@ describe('q', function() {
   // The following private functions are used to help with logging for testing invocation of the
   // promise callbacks.
   function _argToString(arg) {
-    return (typeof arg === 'object' && !(arg instanceof Error)) ? toJson(arg) : '' + arg;
+    return (typeof arg === 'object' && !(isError(arg))) ? toJson(arg) : '' + arg;
   }
 
   function _argumentsToString(args) {