Question: I tried to run `flutter pub get` and I got this error:

```
Error on line 1, column 1 of pubspec.lock: Unexpected character
╷

1 │
│ ^

  ╵
pub upgrade failed (65;   ╵)

```

Answer: 
Delete the file at flutter/packages/flutter\_tools/pubspec.lock then try flutter pub upgrade again.

You may have interrupted the upgrade process before it finished hence the file became invalid.
I got the same error while working.

I deleted **pubspec.lock** file.

then I ran command

`flutter pub get`

It created new **pubspec.lock** file.

Now application runs without any errors.