assert: fix rejects stack trace and operator

This makes sure the stack trace is not removed due to a wrong stack
start function being used. It also fixes the wrong operator caused
by the same reason. This only applies in case an validation object
was used to validate the rejection passed to `assert.reject()` as
first argument.

PR-URL: #27047
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

lib/assert.js

@@ -502,7 +502,7 @@ class Comparison {
   }
 }
 
-function compareExceptionKey(actual, expected, key, message, keys) {
+function compareExceptionKey(actual, expected, key, message, keys, fn) {
   if (!(key in actual) || !isDeepStrictEqual(actual[key], expected[key])) {
     if (!message) {
       // Create placeholder objects to create a nice output.
@@ -513,24 +513,24 @@ function compareExceptionKey(actual, expected, key, message, keys) {
         actual: a,
         expected: b,
         operator: 'deepStrictEqual',
-        stackStartFn: assert.throws
+        stackStartFn: fn
       });
       err.actual = actual;
       err.expected = expected;
-      err.operator = 'throws';
+      err.operator = fn.name;
       throw err;
     }
     innerFail({
       actual,
       expected,
       message,
-      operator: 'throws',
-      stackStartFn: assert.throws
+      operator: fn.name,
+      stackStartFn: fn
     });
   }
 }
 
-function expectedException(actual, expected, msg) {
+function expectedException(actual, expected, msg, fn) {
   if (typeof expected !== 'function') {
     if (isRegExp(expected))
       return expected.test(actual);
@@ -548,9 +548,9 @@ function expectedException(actual, expected, msg) {
         expected,
         message: msg,
         operator: 'deepStrictEqual',
-        stackStartFn: assert.throws
+        stackStartFn: fn
       });
-      err.operator = 'throws';
+      err.operator = fn.name;
       throw err;
     }
 
@@ -570,7 +570,7 @@ function expectedException(actual, expected, msg) {
           expected[key].test(actual[key])) {
         continue;
       }
-      compareExceptionKey(actual, expected, key, msg, keys);
+      compareExceptionKey(actual, expected, key, msg, keys, fn);
     }
     return true;
   }
@@ -676,7 +676,7 @@ function expectsError(stackStartFn, actual, error, message) {
       stackStartFn
     });
   }
-  if (error && expectedException(actual, error, message) === false) {
+  if (error && !expectedException(actual, error, message, stackStartFn)) {
     throw actual;
   }
 }

test/parallel/test-assert-async.js

@@ -96,6 +96,7 @@ promises.push(assert.rejects(
     assert.strictEqual(err.message,
                        'Got unwanted rejection.\nActual message: "Failed"');
     assert.strictEqual(err.operator, 'doesNotReject');
+    assert.ok(err.stack);
     assert.ok(!err.stack.includes('at Function.doesNotReject'));
     return true;
   };
@@ -121,5 +122,29 @@ promises.push(assert.rejects(
   }
 ));
 
+{
+  const handler = (generated, actual, err) => {
+    assert.strictEqual(err.generatedMessage, generated);
+    assert.strictEqual(err.code, 'ERR_ASSERTION');
+    assert.strictEqual(err.actual, actual);
+    assert.strictEqual(err.operator, 'rejects');
+    assert(/rejects/.test(err.stack));
+    return true;
+  };
+  const err = new Error();
+  promises.push(assert.rejects(
+    assert.rejects(Promise.reject(null), { code: 'FOO' }),
+    handler.bind(null, true, null)
+  ));
+  promises.push(assert.rejects(
+    assert.rejects(Promise.reject(5), { code: 'FOO' }, 'AAAAA'),
+    handler.bind(null, false, 5)
+  ));
+  promises.push(assert.rejects(
+    assert.rejects(Promise.reject(err), { code: 'FOO' }, 'AAAAA'),
+    handler.bind(null, false, err)
+  ));
+}
+
 // Make sure all async code gets properly executed.
 Promise.all(promises).then(common.mustCall());