F821 undefined name gives wrong line number (alwasy line 1) when variable is in an f-string

setup:

➤  flake8 --bug-report
{
  "dependencies": [
    {
      "dependency": "setuptools",
      "version": "34.2.0"
    }
  ],
  "platform": {
    "python_implementation": "CPython",
    "python_version": "3.6.0+",
    "system": "Linux"
  },
  "plugins": [
    {
      "plugin": "mccabe",
      "version": "0.6.1"
    },
    {
      "plugin": "pycodestyle",
      "version": "2.3.1"
    },
    {
      "plugin": "pyflakes",
      "version": "1.5.0"
    }
  ],
  "version": "3.3.0"
}

foobar.py:

a = 'this is a test'
b = f'this is a good fstring: {a}'
c = f'this is a bad fstring: {abc}'

➤  flake8 foobar.py 
foobar.py:1:2: F821 undefined name 'abc'

You would expect the error to say line 3 not line 1.

sorry, realised this should have been posted to pyflakes.

closed

Error in pyflakes it slightly different, I'm now a bit confused about whether this should be posted here or on the pyflakes' launchpad.

I'll leave it open here, let me know if you want me to close here and resubmit elsewhere.

reopened

added component:pyflakes fix:pending-upstream-release labels

So https://bugs.launchpad.net/pyflakes/+bug/1666811 was reported this morning. PyFlakes doesn't report columns so the error may be slightly dissimilar. That said, this is definitely a bug in pyflakes.

changed milestone to %3.x.0

Thanks, sorry for missing that. I'm guessing you want the issue left open until it's fixed upstream?