test: show pending exception error in napi tests

Shows the result of the wasPending in the error message if the assertion fails. Backport-PR-URL: #19447 PR-URL: #18413 Reviewed-By: James M Snell <jasnell@gmail.com> Reviewed-By: Rich Trott <rtrott@gmail.com> Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: blairwilcox

test/addons-napi/test_exception/test.js

@@ -20,9 +20,10 @@ const theError = new Error('Some error');
 
  // Test that the exception thrown above was marked as pending
  // before it was handled on the JS side
- assert.strictEqual(test_exception.wasPending(), true,
- 'VM was marked as having an exception pending' +
- ' when it was allowed through');
+ const exception_pending = test_exception.wasPending();
+ assert.strictEqual(exception_pending, true,
+ 'Exception not pending as expected,' +
+ ` .wasPending() returned ${exception_pending}`);
 
  // Test that the native side does not capture a non-existing exception
  returnedError = test_exception.returnException(common.mustCall());
@@ -44,7 +45,8 @@ const theError = new Error('Some error');
  ` ${caughtError} was passed`);
 
  // Test that the exception state remains clear when no exception is thrown
- assert.strictEqual(test_exception.wasPending(), false,
- 'VM was not marked as having an exception pending' +
- ' when none was allowed through');
+ const exception_pending = test_exception.wasPending();
+ assert.strictEqual(exception_pending, false,
+ 'Exception state did not remain clear as expected,' +
+ ` .wasPending() returned ${exception_pending}`);
 }