Expanded the docs from comments in GRCOV-249

[gilescope]

No description provided.

[gilescope]

Fixes #249

[codecov-io]

Codecov Report

Merging #387 into master will not change coverage by %.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #387   +/-   ##
=======================================
  Coverage   65.27%   65.27%           
=======================================
  Files          12       12           
  Lines        4101     4101           
  Branches     1033     1033           
=======================================
  Hits         2677     2677           
  Misses        622      622           
  Partials      802      802           

---

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[gilescope]

Some pretty epic coverage swings considering it's just the readme that's changed??

[Nokel81]

Would you be able to add a little blurb on each of the -t options? (In a list format or something). I think that new users would fine it quite useful.

[gilescope]

@Nokel81 how's that looking? Is there any way we can improve it more (short of writing a cargo-grcov crate)?

[Nokel81]

Last I checked grcov doesn't work on macos. But other then that this looks good.

[gilescope]

Luckily I didn't scrub OSX when I switched to nixos. I'm going to stand my ground here - just checked OSX, works fine for a small project. I'm not saying there might not be bugs on OSX/Windows but certainly for some projects it works on all three major OSes.

[gilescope]

(And btw that's one of the reason's I'm a big fan. As far as I know grcov is the only rust coverage mechanism that work on all three OSes.)

[Nokel81]

I was referring to rust-lang/rust#63047 since this is what I ran into.

[gilescope]

@Nokel81 I guess we don't know how many are using grcov on mac with no problems? Is there a set of rustc flags that did work for you? - if so we could let people know those alternative settings should people run into trouble.

[Nokel81]

I didn't, I switched to running in Docker containers...

[gilescope]

Is the PR an improvement or not on the current docs? If so let's ship it and give users an easier time. If not please feel free to go in and change the PR to tweak things to how you want it or suggest what I can change - I'd like to get closure on this PR.

[gilescope]

(Sorry just juggling a lot of things at the moment. I just want there to be better docs)

[Nokel81]

(sorry for the blocking style comments, I just know that as a user on macos I would be confused if the project says it works on macos but then I run into such a linking error)

I agree that these doc edits will help users

[gilescope]

We could categorise the open issues by OS and provide links to the open issues by operating system. But we cannot say it doesn’t work on macos if there are counterexamples.

We could confidently say it works on macos for some definition of ‘works’ and dependent on your codebase. :-)

(We should probably include windows in that definition of working... I have had some issues there)

_{Sent with GitHawk}

[calixteman]

Maybe we should add a word about the fact that gcov (with the correct version) is required when the build has been made with gcc but we've an internal parser for gcno/gcda coming from llvm (clang/rustc).

[gilescope]

Rebased and incorporated feedback. Anything left to change?

[marco-c]

Thanks!