title: How to upgrade packages in VSCode/flutter?
body: <p>I'm using VS Code on a flutter project. I just edited pubspec.yaml to point to a later version of a package, and it automatically ran 'flutter packages get'. In my '/development//flutter/.pub-cache/hosted/pub.dartlang.org' directory, I can see both versions. But when I compile, it looks like it's still using the old version. I tried various things like 'flutter packages upgrade', 'flutter clean', etc., but to no avail. Looking at the 2 package versions' source code, I can see the change I want in the newer version. How do I point to the new package? Thanks.</p>
  
  <p>Update:</p>
  
  <p>It's the 'ethereum' package that's not updating. I had used the 3.0.0 version (method expects 2 args), and then switched to the 3.1.0 version (method expects 3 args). But compiling with a 3 arg call balks with incorrect argument count:</p>
  
  <pre><code>client.admin.personalSendTransaction(BigInt.parse(currentAddress), currentPassword,{});
  
  [dart] Too many positional arguments: 2 expected, but 3 found. [extra_positional_arguments_could_be_named]
  </code></pre>
  
  <p>Yet hovering over the method call does show it expects 3 args:</p>
  
  <pre><code>personalSendTransaction(BigInt address, String passphrase, {BigInt to, BigInt data, int gas, int gasPrice, int value, int nonce, int condition, bool conditionIsTimestamp: false}) → Future&lt;BigInt&gt;
  </code></pre>
  
  <p>pubspec.yaml:</p>
  
  <pre><code>    dependencies:
    flutter:
      sdk: flutter
  
    # The following adds the Cupertino Icons font to your application.
    # Use with the CupertinoIcons class for iOS style icons.
    cupertino_icons: ^0.1.2
  
    # Get package(s) for talking to ethereum node
    # web3dart: '&gt;=0.3.0'
    ethereum: ^3.1.0
  
    # read barcodes and QR codes
    barcode_scan: ^0.0.3
  
    # Generate a QR code
    qr: ^1.0.1
  
    # Display as actual symbol
    qr_flutter: ^1.1.5
  
  dev_dependencies:
    flutter_test:
      sdk: flutter
  </code></pre>
  
  <p>In pubspec.lock:</p>
  
  <pre><code>  ethereum:
      dependency: "direct main"
      description:
        name: ethereum
        url: "https://pub.dartlang.org"
      source: hosted
      version: "3.1.0"
  </code></pre>
  
  <p>Version 3.1.0 is what I want to be used.</p>
  
  <p>Running 'flutter packages upgrade resolved' yields:</p>
  
  <pre><code>[Gregorys-iMac]:(gkd) ~/Programs/wine_track $ flutter packages upgrade resolved
  Running "flutter packages upgrade" in ....                   2.7s
  </code></pre>
  
  <p>In the package cache, I have both:</p>
  
  <pre><code>/Users/gkd/development//flutter/.pub-cache/hosted/pub.dartlang.org/ethereum-3.0.0/lib/src/api/ethereum_api_admin.dart
  
  /Users/gkd/development//flutter/.pub-cache/hosted/pub.dartlang.org/ethereum-3.1.0/lib/src/api/ethereum_api_admin.dart
  </code></pre>