devToolsInspectorUri method Null safety

Implementation

@visibleForTesting
String devToolsInspectorUri(String inspectorRef) {
  assert(activeDevToolsServerAddress != null);
  assert(connectedVmServiceUri != null);

  final Uri uri = Uri.parse(activeDevToolsServerAddress!).replace(
    queryParameters: <String, dynamic>{
      'uri': connectedVmServiceUri,
      'inspectorRef': inspectorRef,
    },
  );

  // We cannot add the '/#/inspector' path by means of
  // [Uri.replace(path: '/#/inspector')] because the '#' character will be
  // encoded when we try to print the url as a string. DevTools will not
  // load properly if this character is encoded in the url.
  // Related: https://github.com/flutter/devtools/issues/2475.
  final String devToolsInspectorUri = uri.toString();
  final int startQueryParamIndex = devToolsInspectorUri.indexOf('?');
  // The query parameter character '?' should be present because we manually
  // added query parameters above.
  assert(startQueryParamIndex != -1);
  return '${devToolsInspectorUri.substring(0, startQueryParamIndex)}'
      '/#/inspector'
      '${devToolsInspectorUri.substring(startQueryParamIndex)}';
}