Add support for .nomad and .tfvars (HCL)

[CalebAlbers]

HashiCorp Nomad users occasionally use the (discouraged) .nomad extension for HCL-based configurations. Likewise, .tfvars is frequently used in the Terraform realm. Both of these file formats follow the same form as HCL, just with differing extensions.

As an aside, both .hcl and tf files should ideally use the more idomatic # single-line format over single-line // or multi-line /* */ formats. I would love to change that in a future PR if you're open to it, but I recognize that it could come across as a disruptive change.

Thanks a ton for building this!

[google-cla]

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[CalebAlbers]

Side note - I'll have the CLA thing resolved soon - just put in the request to be covered under the HashiCorp CLA 🙂

[CalebAlbers]

Okay - CLA is signed, so this should be all prepped for review now 🙂

[codecov-commenter]

Codecov Report

Merging #116 (12435d4) into master (d40d757) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #116   +/-   ##
=======================================
  Coverage   48.60%   48.60%           
=======================================
  Files           2        2           
  Lines         251      251           
=======================================
  Hits          122      122           
  Misses        122      122           
  Partials        7        7           

Impacted Files	Coverage Δ
main.go	41.62% <100.00%> (ø)

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[willnorris]

we've started to move away from all of the files in testdata (though obviously never finished). But could you go ahead and add this to our newer test case at https://github.com/google/addlicense/blob/master/main_test.go#L319 ?

[CalebAlbers]

we've started to move away from all of the files in testdata (though obviously never finished). But could you go ahead and add this to our newer test case at https://github.com/google/addlicense/blob/master/main_test.go#L319 ?

Thanks @willnorris! I flipped to the test table strategy in 12435d4. Would you be open to me creating another PR to move the remaining file types into using that approach?

[willnorris]

Would you be open to me creating another PR to move the remaining file types into using that approach?

Yeah, that was always the intent. Most (all?) of the supported filetypes should already be covered by the new tests, but it's worth double checking. It's been a while since I looked at this, but I seem to recall there were still a few things the existing tests covered that needed to be migrated over. Maybe actually reading a file off disk, beyond just verifying that a given file extension maps to the write comment syntax? But yeah, if you wanna take a stab at this, feel free to open a new issue for finishing the test migration, and we can continue there.