dart cannot find existing file

Question

given the code below

import 'dart:convert';
import 'dart:io';

void main() {
  print('open file');
  final path = stdin.readLineSync(encoding: utf8);
  if (path == null) {
    throw Exception('no path provided');
  }
  final uri = Uri.tryParse(path);
  if (uri == null) {
    throw Exception('invalid uri');
  }
  final file = File.fromUri(uri);
  if (file.existsSync()) {
    print(file.readAsStringSync());
    return;
  }

  throw ('file not found: ${uri.path}');
}

if I run the commands below

dart run bin/console_test.dart
open file
~/Desktop/test_folder/readme.md

I get the error file not found: ~/Desktop/test_folder/readme.md
but a normal cat command open the file easily

cat ~/Desktop/test_folder/readme.md
hello world!%

what am I missing?

Answer 1

here is a workaround based on this answer

import 'dart:convert';
import 'dart:io' as io;
import 'package:path/path.dart' as path;

void main() {
  print('open file');

  final maybePath = io.stdin.readLineSync(encoding: utf8);

  if (maybePath == null) {
    throw Exception('no path provided');
  }

  final maybeRoot = io.Platform.isWindows
      ? io.Platform.environment['USERPROFILE']
      : io.Platform.environment['HOME'];

  if (maybeRoot == null) {
    throw Exception('no root found');
  }

  final pathSegments = maybePath.split('');
  if (pathSegments.first == '~') {
    pathSegments.removeAt(0);
  }

  final realPath = path.absolute([maybeRoot, ...pathSegments].join());
  final uri = Uri.tryParse(realPath);

  if (uri == null) {
    throw Exception('could not find root');
  }

  final file = io.File(uri.toFilePath(windows: io.Platform.isWindows));

  if (file.existsSync()) {
    print(file.readAsStringSync());
    return;
  }

  throw ('file not found: ${file.path}');
}