diff --git a/lib/test.js b/lib/test.js
index 4d6182c0..463e86d0 100644
--- a/lib/test.js
+++ b/lib/test.js
@@ -257,7 +257,8 @@ Test.prototype._assert = function assert(ok, opts) {
     this._ok = !!(this._ok && ok);
 
     if (!ok && !res.todo) {
-        res.error = defined(extra.error, opts.error, new Error(res.name));
+        var anError = res.name instanceof Error ? res.name : new Error(res.name);
+        res.error = defined(extra.error, opts.error, anError);
     }
 
     if (!ok) {
diff --git a/test/async-await.js b/test/async-await.js
index 02aff917..bdc4fc0a 100644
--- a/test/async-await.js
+++ b/test/async-await.js
@@ -219,7 +219,8 @@ tap.test('async-error', function (t) {
             '  ---',
             '    operator: fail',
             '    stack: |-',
-            '      Error: Error: oopsie',
+            '      Error: oopsie',
+            '          at Test.myTest ($TEST/async-await/async-error.js:$LINE:$COL)',
             '          [... stack stripped ...]',
             '  ...',
             '',
diff --git a/test/promise_fail.js b/test/promise_fail.js
index ddc93412..eb512bed 100644
--- a/test/promise_fail.js
+++ b/test/promise_fail.js
@@ -34,7 +34,10 @@ tap.test('callback returning rejected promise should cause that test (and only t
             '  ---',
             '    operator: fail',
             '    stack: |-',
-            '      Error: Error: rejection message',
+            '      Error: rejection message',
+            '          at $TEST/promises/fail.js:$LINE:$COL',
+            '          [... stack stripped ...]',
+            '          at Test.<anonymous> ($TEST/promises/fail.js:$LINE:$COL)',
             '          [... stack stripped ...]',
             '  ...',
             '# after',
@@ -78,7 +81,10 @@ tap.test('subtest callback returning rejected promise should cause that subtest
             '  ---',
             '    operator: fail',
             '    stack: |-',
-            '      Error: Error: rejection message',
+            '      Error: rejection message',
+            '          at $TEST/promises/subTests.js:$LINE:$COL',
+            '          [... stack stripped ...]',
+            '          at Test.<anonymous> ($TEST/promises/subTests.js:$LINE:$COL)',
             '          [... stack stripped ...]',
             '  ...',
             '# sub test that should pass',