Re: [PATCH v3 1/2] difftool: add a skeleton for the upcoming builtin

> On Sat, Nov 26, 2016 at 01:22:28PM +0100, Johannes Schindelin wrote:
> 
> > In other words, GIT_CONFIG_PARAMETERS is *explicitly scrubbed* from the
> > environment when we run our tests (by the code block between the "before"
> > and the "after" statements in the diff above).
> 
> Sorry if I wasn't clear. I meant to modify t7800 to run the tests twice,
> once with the existing script and once with the builtin. I.e., to set
> the variable after test-lib.sh has done its scrubbing, and then use a
> loop or similar to go through the tests twice.
> 
> If you want to control it from outside the test script, you'd need
> something like:
> 
>   if test "$GIT_TEST_DIFFTOOL" = "builtin"