diff --git a/test/error.js b/test/error.js
index 18dcb0bd..94c96ed9 100644
--- a/test/error.js
+++ b/test/error.js
@@ -20,7 +20,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      undefined',
             '    actual: |-',
-            '      [Error: this is a message]',
+            '      ' + ('cause' in Error.prototype ? '{ [Error: this is a message] [cause]: undefined }' : '[Error: this is a message]'),
             '    at: Test.<anonymous> ($TEST/error.js:$LINE:$COL)',
             '    stack: |-',
             '      Error: this is a message',
diff --git a/test/stackTrace.js b/test/stackTrace.js
index 8ae0ee6b..6061f9ca 100644
--- a/test/stackTrace.js
+++ b/test/stackTrace.js
@@ -14,6 +14,8 @@ tap.test('preserves stack trace with newlines', function (tt) {
     var parser = stream.pipe(tapParser());
     var stackTrace = 'foo\n  bar';
 
+    var inspected = 'cause' in Error.prototype ? '{ [Error: Preserve stack] [cause]: undefined }' : '[Error: Preserve stack]';
+
     parser.once('assert', function (data) {
         delete data.diag.at;
         tt.deepEqual(data, {
@@ -24,7 +26,7 @@ tap.test('preserves stack trace with newlines', function (tt) {
                 stack: stackTrace,
                 operator: 'error',
                 expected: 'undefined',
-                actual: '[Error: Preserve stack]'
+                actual: inspected
             }
         });
     });
@@ -41,7 +43,7 @@ tap.test('preserves stack trace with newlines', function (tt) {
             + '    expected: |-\n'
             + '      undefined\n'
             + '    actual: |-\n'
-            + '      [Error: Preserve stack]\n'
+            + '      ' + inspected + '\n'
             + '    stack: |-\n'
             + '      foo\n'
             + '        bar\n'
@@ -57,7 +59,7 @@ tap.test('preserves stack trace with newlines', function (tt) {
             stack: stackTrace,
             operator: 'error',
             expected: 'undefined',
-            actual: '[Error: Preserve stack]'
+            actual: inspected
         });
     }));
 
diff --git a/test/throws.js b/test/throws.js
index 77d92cb5..a2daf100 100644
--- a/test/throws.js
+++ b/test/throws.js
@@ -26,6 +26,8 @@ var thrower = function () { throw messageGetterError; };
 tap.test('failures', function (tt) {
     tt.plan(1);
 
+    var maybeCause = 'cause' in Error.prototype ? '[cause]: undefined, ' : '';
+
     var test = tape.createHarness();
     test.createStream().pipe(concat(function (body) {
         tt.same(stripFullStack(body.toString('utf8')), [
@@ -37,7 +39,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      undefined',
             '    actual: |-',
-            '      { [TypeError: ' + getNonFunctionMessage() + "] message: '" + getNonFunctionMessage() + "' }",
+            '      { [TypeError: ' + getNonFunctionMessage() + '] ' + maybeCause + "message: '" + getNonFunctionMessage() + "' }",
             '    at: Test.<anonymous> ($TEST/throws.js:$LINE:$COL)',
             '    stack: |-',
             String('      TypeError: ' + getNonFunctionMessage(undefined)),
@@ -51,7 +53,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      undefined',
             '    actual: |-',
-            '      { [TypeError: ' + getNonFunctionMessage(null) + "] message: '" + getNonFunctionMessage(null) + "' }",
+            '      { [TypeError: ' + getNonFunctionMessage(null) + '] ' + maybeCause + "message: '" + getNonFunctionMessage(null) + "' }",
             '    at: Test.<anonymous> ($TEST/throws.js:$LINE:$COL)',
             '    stack: |-',
             String('      TypeError: ' + getNonFunctionMessage(null)),
@@ -65,7 +67,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      undefined',
             '    actual: |-',
-            '      { [TypeError: ' + getNonFunctionMessage(true) + "] message: '" + getNonFunctionMessage(true) + "' }",
+            '      { [TypeError: ' + getNonFunctionMessage(true) + '] ' + maybeCause + "message: '" + getNonFunctionMessage(true) + "' }",
             '    at: Test.<anonymous> ($TEST/throws.js:$LINE:$COL)',
             '    stack: |-',
             String('      TypeError: ' + getNonFunctionMessage(true)),
@@ -79,7 +81,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      undefined',
             '    actual: |-',
-            '      { [TypeError: ' + getNonFunctionMessage(false) + "] message: '" + getNonFunctionMessage(false) + "' }",
+            '      { [TypeError: ' + getNonFunctionMessage(false) + '] ' + maybeCause + "message: '" + getNonFunctionMessage(false) + "' }",
             '    at: Test.<anonymous> ($TEST/throws.js:$LINE:$COL)',
             '    stack: |-',
             String('      TypeError: ' + getNonFunctionMessage(false)),
@@ -93,7 +95,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      undefined',
             '    actual: |-',
-            '      { [TypeError: ' + getNonFunctionMessage('abc') + "] message: '" + getNonFunctionMessage('abc') + "' }",
+            '      { [TypeError: ' + getNonFunctionMessage('abc') + '] ' + maybeCause + "message: '" + getNonFunctionMessage('abc') + "' }",
             '    at: Test.<anonymous> ($TEST/throws.js:$LINE:$COL)',
             '    stack: |-',
             String('      TypeError: ' + getNonFunctionMessage('abc')),
@@ -107,7 +109,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      undefined',
             '    actual: |-',
-            '      { [TypeError: ' + getNonFunctionMessage(/a/g) + "] message: '" + getNonFunctionMessage(/a/g) + "' }",
+            '      { [TypeError: ' + getNonFunctionMessage(/a/g) + '] ' + maybeCause + "message: '" + getNonFunctionMessage(/a/g) + "' }",
             '    at: Test.<anonymous> ($TEST/throws.js:$LINE:$COL)',
             '    stack: |-',
             String('      TypeError: ' + getNonFunctionMessage(/a/g)),
@@ -121,7 +123,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      undefined',
             '    actual: |-',
-            '      { [TypeError: ' + getNonFunctionMessage([]) + "] message: '" + getNonFunctionMessage([]) + "' }",
+            '      { [TypeError: ' + getNonFunctionMessage([]) + '] ' + maybeCause + "message: '" + getNonFunctionMessage([]) + "' }",
             '    at: Test.<anonymous> ($TEST/throws.js:$LINE:$COL)',
             '    stack: |-',
             String('      TypeError: ' + getNonFunctionMessage([])),
@@ -135,7 +137,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      undefined',
             '    actual: |-',
-            '      { [TypeError: ' + getNonFunctionMessage({}) + "] message: '" + getNonFunctionMessage({}) + "' }",
+            '      { [TypeError: ' + getNonFunctionMessage({}) + '] ' + maybeCause + "message: '" + getNonFunctionMessage({}) + "' }",
             '    at: Test.<anonymous> ($TEST/throws.js:$LINE:$COL)',
             '    stack: |-',
             String('      TypeError: ' + getNonFunctionMessage({})),
@@ -169,7 +171,7 @@ tap.test('failures', function (tt) {
             '    expected: |-',
             '      [Function: TypeError]',
             '    actual: |-',
-            '      { [RangeError: actual!] ' + ('cause' in Error.prototype ? '[cause]: undefined, ' : '') + "message: 'actual!' }",
+            '      { [RangeError: actual!] ' + maybeCause + "message: 'actual!' }",
             '    at: Test.<anonymous> ($TEST/throws.js:$LINE:$COL)',
             '    stack: |-',
             '      RangeError: actual!',