Crashing in runner.py due to AttributeError raised by checking None for keys

Describe the bug I am getting a crash similar in appearance to #118 but for Terraform and not CloudFormation.

Scanning file: /some_directory/some-file.tf
full_file_path is /other_directory/some_directory/some-file.tf
Traceback (most recent call last):
  File "/my_path/bin/checkov", line 5, in <module>
    run()
  File "/my_path/lib/python3.7/site-packages/checkov/main.py", line 108, in run
    guidelines=guidelines, bc_integration=bc_integration)
  File "/my_path/lib/python3.7/site-packages/checkov/common/runners/runner_registry.py", line 35, in run
    runner_filter=self.runner_filter, collect_skip_comments=collect_skip_comments)
  File "/my_path/lib/python3.7/site-packages/checkov/terraform/runner.py", line 78, in run
    self.check_tf_definition(report, root_folder, runner_filter, collect_skip_comments)
  File "/my_path/lib/python3.7/site-packages/checkov/terraform/runner.py", line 100, in check_tf_definition
    scanned_file, runner_filter, abs_referrer)
  File "/my_path/lib/python3.7/site-packages/checkov/terraform/runner.py", line 104, in run_all_blocks
    for block_type in definition.keys():
AttributeError: 'NoneType' object has no attribute 'keys'

To Reproduce edit: See https://github.com/bridgecrewio/checkov/issues/941#issuecomment-790803047

That’s the thing 😢 It’s real hard to reproduce, if I run checkov just on the file that it crashes on, things work fine! If I run it on just the last 10 files it scans before crashing, things work fine. For testing this, I’d recommend you simply run this on a big repo with a lot of output from find . -type f -name "*.tf" and then turn all the files into individual --file arguments, like my cool checkov wrapper package does. e.g. checkov --check CKV_AWS_88 --file fileA.tf --fileB.tf (to save time, I just limited this to 1 check, but it could be any other check id)

Steps to reproduce the behavior:

1. Run cli command checkov --check CKV_AWS_88 --file fileA.tf --fileB.tf on a ton of --file arguments. Pray it triggers the bug.
2. See error

Expected behavior No crashing.

Desktop (please complete the following information):

• OS: OS X
• Checkov Version: the latest as of today: 1.0.825

[robeden]

That might make sense given how it loops over things? Hard to say for sure without being able to reproduce, but I’m pretty sure I have a change that will avoid the problem.

[robeden]

Ok. Normality restored. 🤪