Re: customizing coverage

[Ludovic Courtès]

Hi!

Thien-Thi Nguyen <address@hidden> skribis:

> This raises two followup questions:
>
> - Can i use the following in rcs/release.nix?
>   (I.e., will it interfere badly w/ hydra machinery?)
>
>    rcs/release.nix |    2 +-
>    1 files changed, 1 insertions(+), 1 deletions(-)
>   
>   diff --git a/rcs/release.nix b/rcs/release.nix
>   index c8d2237..b63e318 100644
>   --- a/rcs/release.nix
>   +++ b/rcs/release.nix
>   @@ -70,7 +70,7 @@ in
>    
>          coverage = pkgs: {
>            buildInputs = [pkgs.ed];
>   -        inherit configureFlags;
>   +        configureFlags = meta.configureFlags + " --enable-coverage";
>          };
>    
>        };

Under the hood, the coverage stuff uses the ‘coverageAnalysis’ function
(see ../gnu-jobs.nix), which essentially passes ‘--coverage’ in CFLAGS.
Its definition can be seen here:

  
https://nixos.org/repos/nix/nixpkgs/trunk/pkgs/build-support/release/nix-build.nix

So presumably, what you show above shouldn’t interfere badly, and in
fact shouldn’t make any difference.

> - If so, is that syntax correct?  Is there a better way to append?

There are 1 problem: ‘meta.configureFlags’ means “get the attribute
named ‘configureFlags’ from the attribute set stored in the
lexically-scoped variable ‘meta’.”  And ‘meta’ has no such field.  So
instead, it should be:

  configureFlags = configureFlags + " --enable-coverage";

Note that ‘+’ is like ‘string-append’.

Thanks,
Ludo’.