Fix cause chain backtraces

src/browser/transforms.js

@@ -181,9 +181,9 @@ function addBodyMessage(item, options, callback) {
   callback(null, item);
 }
 
-function stackFromItem(item) {
+function stackFromItem(item, stackInfo = null) {
   // Transform a TraceKit stackInfo object into a Rollbar trace
-  var stack = item.stackInfo.stack;
+  let stack = (stackInfo || item.stackInfo).stack;
   if (
     stack &&
     stack.length === 0 &&
@@ -230,7 +230,7 @@ function addBodyTrace(item, options, callback) {
 function buildTrace(item, stackInfo, options) {
   var description = item && item.data.description;
   var custom = item && item.custom;
-  var stack = stackFromItem(item);
+  var stack = stackFromItem(item, stackInfo);
 
   var guess = errorParser.guessErrorClass(stackInfo.message);
   var className = errorClass(stackInfo, guess[0], options);

test/browser.rollbar.test.ts

@@ -538,6 +538,7 @@ describe('options.captureUncaught', function () {
       captureUncaught: false,
     });
   });
+
   it('should send DOMException as trace_chain', async function () {
     const server = window.server;
     stubResponse(server);
@@ -558,9 +559,15 @@ describe('options.captureUncaught', function () {
 
     const body = JSON.parse(server.requests[0].requestBody);
 
-    expect(body.data.body.trace_chain[0].exception.message).to.eql(
-      'test DOMException',
-    );
+    expect(body.data.body.trace_chain[0].exception).to.eql({
+      class: 'Error',
+      message: 'test DOMException',
+      description: 'Uncaught Error: test DOMException',
+    });
+    expect(body.data.body.trace_chain[1].exception).to.eql({
+      class: 'DOMException',
+      message: 'test DOMException',
+    });
 
     // karma doesn't unload the browser between tests, so the onerror handler
     // will remain installed. Unset captureUncaught so the onerror handler
@@ -570,7 +577,7 @@ describe('options.captureUncaught', function () {
     });
   });
 
-  it('should capture exta frames when stackTraceLimit is set', async function () {
+  it('should capture extra frames when stackTraceLimit is set', async function () {
     const server = window.server;
     stubResponse(server);
     server.requests.length = 0;

test/browser.transforms.test.ts

@@ -460,6 +460,9 @@ describe('addBody', function () {
         expect(i.data.body.trace_chain[1].exception.message).to.eql(
           'nested error',
         );
+        expect(i.data.body.trace_chain[0].frames.at(-1).lineno).to.not.eql(
+          i.data.body.trace_chain[1].frames.at(-1).lineno,
+        );
         done(e);
       });
     });