Dart lacks a way to create an error chain about sdk

[lrhn]

This sounds like something that should apply to exceptions, not errors.
You shouldn't handle or transform an Error, because they shouldn't be happening at all. And if you do, it should be because someone higher up will want to catch and handle it, which means it should be rehtrown as an Exception, not an Error.

It may make sense to give Exception a cause (which may be an Error).
It probably means having a default toString which prints the chain of stack traces. Maybe avoid common suffixes in the stack traces, like Java does. More work, but you shouldn't be doing toString on Exception to begin with, except for debugging - you should handle the problem instead.

[dart-github-bot]

Summary: Dart currently lacks a mechanism to create error chains, making it difficult to preserve original error information and stack traces when re-throwing errors. This leads to loss of context and potential confusion for debugging tools and error reporting libraries.

[rrousselGit]

I'm not sure why this would be unique to exceptions. We could convert an Exception into an Error, and include a cause in the error.

For example, a function that takes a JSON as String could convert a FormatException into an ArgumentError, and pass the FormatException as cause to that ArgumentError.

void function(String json) {
  try {
    jsonCode(json);
  } on FormatException catch (e, s) {
    throw ArgumentError('json is not a valid JSON', cause: Cause(e, s));
  }
}

[lrhn]

Handling an exception by throwing an error ... is a reasonable use-case.