Cumulative code coverage?

[Seb]

On Wednesday, 21 March 2018 at 16:39:48 UTC, H. S. Teoh wrote:
> Is it possible to get cumulative code coverage using dmd? I.e., 
> accumulate code coverage stats over a series of runs from an 
> external test suite.  Currently, it seems that compiling with 
> -cov will just overwrite the *.lst files from previous runs.  
> Do I have to merge the .lst files externally?
>
> I'm currently writing an external test suite for one of my 
> projects, and obviously, each individual test isn't going to 
> cover the entire code. So the idea is to write a series of 
> tests that cumulatively test all code paths.
>
>
> T

Yes, either set dmd_coverSetMerge(true) or pass --DRT-covopt 
"merge:1" to your program.
You can also set the environment variable DRT_COVOPT, but I think 
you need to enable this by setting rt_envvars_enabled to true 
before.

https://dlang.org/phobos/core_runtime.html#.dmd_coverSetMerge
https://dlang.org/changelog/2.078.0.html#covopts