Bug 857648 part 5. Expose a .stack property on DOMExceptions. r=khuey

browser/devtools/scratchpad/test/browser_scratchpad_display_non_error_exceptions.js

@@ -63,7 +63,8 @@ function runTests()
     method: "display",
     code: error4,
     result: error4 + openComment + "Exception: Node cannot be inserted " +
-            "at the specified point in the hierarchy\n@1" + closeComment,
+            "at the specified point in the hierarchy\n@" +
+            scratchpad.uniqueName + ":1:0" + closeComment,
     label: "Alternative format error display output"
   },
   {
@@ -100,7 +101,8 @@ function runTests()
     method: "run",
     code: error4,
     result: error4 + openComment + "Exception: Node cannot be inserted " +
-            "at the specified point in the hierarchy\n@1" + closeComment,
+            "at the specified point in the hierarchy\n@" +
+            scratchpad.uniqueName + ":1:0" + closeComment,
     label: "Alternative format error run output"
   }];
 

dom/base/DOMException.cpp

@@ -22,6 +22,7 @@
 #include "xpcprivate.h"
 
 #include "mozilla/dom/DOMExceptionBinding.h"
+#include "mozilla/ErrorResult.h"
 
 using namespace mozilla;
 
@@ -553,6 +554,14 @@ Exception::GetData() const
   return data.forget();
 }
 
+void
+Exception::GetStack(nsAString& aStack, ErrorResult& aRv) const
+{
+  if (mLocation) {
+    aRv = mLocation->GetFormattedStack(aStack);
+  }
+}
+
 void
 Exception::Stringify(nsString& retval)
 {

dom/base/DOMException.h

@@ -32,6 +32,8 @@ NS_GetNameAndMessageForDOMNSResult(nsresult aNSResult, nsACString& aName,
                                    uint16_t* aCode = nullptr);
 
 namespace mozilla {
+class ErrorResult;
+
 namespace dom {
 
 #define MOZILLA_EXCEPTION_IID \
@@ -81,6 +83,8 @@ public:
 
   already_AddRefed<nsISupports> GetData() const;
 
+  void GetStack(nsAString& aStack, ErrorResult& aRv) const;
+
   void Stringify(nsString& retval);
 
   // XPCOM factory ctor.

dom/webidl/DOMException.webidl

@@ -56,6 +56,10 @@ interface ExceptionMembers
 
   // Arbitary data for the implementation.
   readonly attribute nsISupports?            data;
+
+  // Formatted exception stack
+  [Throws, Replaceable]
+  readonly attribute DOMString               stack;
 };
 
 [NoInterfaceObject]