call_wd() returns wrong directory in tests run by run_test_dir()

[reedacartwright]

First, assume that getwd() returns "pkg". Then if I run tests via run_test_dir("tests"), and use call_wd() to access the previous working directory, it will return "pkg/tests" instead of "pkg".

I believe that the bug can be traced to https://github.com/markvanderloo/tinytest/blob/master/pkg/R/tinytest.R#L20

While set_call_wd() contains logic to not update CALLDIR if it is already set, it does not have logic to prevent it from being unset prematurely. The logic flow looks like this:

1. run_test_dir("tests") calls set_call_wd("pkg") and changes directory to "tests" => CALLDIR set to "pkg"
2. run_test_file("test-a.R") calls set_call_wd("pkg/tests") and changes directory to "tests" => CALLDIR not changed
3. run_test_file("test-a.R") calls set_call_wd("") on exit and changes directory to "tests" => CALLDIR set to ""
4. run_test_file("test-b.R") calls set_call_wd("pkg/tests") and changes directory to "tests" => CALLDIR set to "pkg/tests"

I think the simplest solution would be:

1. set_call_wd(dir) to push dir onto the back of CALLDIR and
2. set_call_wd("") to pop the back of CALLDIR
3. And get_call_wd() only return CALLDIR[1]

[markvanderloo]

Thanks, I will look into this. it will require some heavy reverse dependency testing.