Prevent converting NUL characters in strings read by licensecheck

[giordano]

Ref JuliaEcosystem/PackageAnalyzer.jl#14.

I don't have the time to add tests now, if you have a good idea how to do that,
please go ahead! (Edit: I have a couple of ideas for how to test this, but I'll have the time to do it only tomorrow night)

[codecov]

Codecov Report

Merging #6 (61d5b7b) into main (23ce74b) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##              main        #6   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            1         2    +1     
  Lines            5        35   +30     
=========================================
+ Hits             5        35   +30     

Impacted Files	Coverage Δ
src/LicenseCheck.jl	100.00% <100.00%> (ø)
src/find_licenses.jl	100.00% <100.00%> (ø)

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[ericphanson]

Thanks @giordano, this seems great. I think for a test we could just generate a test file by something like

using Random
str = randstring(100);
str_bytes = Vector{UInt8}(str);
str_bytes[10] = 0;
str2 = String(str_bytes);
write("test/malformed_file_dir/malformed_file.txt", str2)

and then do license_check("test/malformed_file_dir") or something like that. We could also put an actual license in that directory and check that it finds the license (and doesn't throw on seeing the bad file).