EOL semantics by adding .gitattributes and changing tsconfig.json

[MarkSeufert]

Description:
This PR solves issue #1529, which addresses the non-normality of end-of-line (EOL) semantics between operating systems. There are two main concerns in this issue:

1. The version script uses os.EOL. On windows, EOL could mean either CRLF or LF depending on the git setting of autocrlf. On Linux and Mac, os.EOL means LF.
   To solve this, a .gitattributes file was added in the root directory which specifies the EOL semantics for certain types of files. OS independent files should always use LF, whereas windows specific files (.bat, .cmd, etc) should use CRLF. To show that this works, I ran npm install on a windows machine and viewed one of the resulting version.ts files. This can be seen below:
   
   I then pushed it to my branch to trigger the .gitattributes functionality and then viewed the same version.ts file, seen below:
   
   Notice how the new file only uses LF instead of CRLF. Success!

2. The generated js files have inconsistent line endings, which causes differences between an npm module that is published on windows instead of on linux. To solve this, I found all the tsconfig.json files and added a single line: "newLine": "LF". This means that all the generated js files inside the node_modules folders will use LF as their EOL.

[codecov]

Codecov Report

Merging #1550 into master will decrease coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1550      +/-   ##
==========================================
- Coverage   93.18%   93.16%   -0.03%     
==========================================
  Files         156      156              
  Lines        4854     4854              
  Branches      986      986              
==========================================
- Hits         4523     4522       -1     
- Misses        331      332       +1     

Impacted Files	Coverage Δ
packages/opentelemetry-tracing/src/Span.ts	97.14% <0.00%> (-0.96%)	⬇️

[vmarchaud]

Could you se the option inside the tsconfig.base inside the packages folder instead ?

[MarkSeufert]

Alright I moved the option into the tsconfig.base instead. I noticed that some of the tsconfig.json files import from the tsconfig.es5 file instead of the tsconfig.base... would it make sense to add the option into tsconfig.es5 as well?

[vmarchaud]

@MarkSeufert Yeah i thinks so

[Flarna]

I think

opentelemetry-js/scripts/version-update.js

Line 48 in 3bc4d57

fs.writeFileSync(fileUrl, content.replace(/\n/g, os.EOL));

needs to be changed to use \n instead os.EOL .
os.EOL is CRLF on windows and LF on unixes.
\n is LF independent of OS used.

[dyladan]

I think

opentelemetry-js/scripts/version-update.js

Line 48 in 3bc4d57

fs.writeFileSync(fileUrl, content.replace(/\n/g, os.EOL));

needs to be changed to use \n instead os.EOL .
os.EOL is CRLF on windows and LF on unixes.
\n is LF independent of OS used.

This script only writes the TS files which can have an OS specific line ending I believe which will be converted by git. The output JS will still only use LF.

[Flarna]

As far as I remember it's a good idea to use git add --renormalize . to convert any file currently committed with other line ending then .gitattributes requests.

[Flarna]

This script only writes the TS files which can have an OS specific line ending I believe which will be converted by git. The output JS will still only use LF.

The target of this PR is to have *.ts files with LF only after a fresh checkout independent of OS. The version script should not write OS dependent line endings then.

[MarkSeufert]

Right... I forgot that was a regex haha

[dyladan]

As far as I remember it's a good idea to use git add --renormalize . to convert any file currently committed with other line ending then .gitattributes requests.

@MarkSeufert can you take care of this?

[MarkSeufert]

I ran git add --renormalize . but no files were changed which I'm pretty sure means all the files in the repo already have the correct file endings.