Unfortunately, using `attrsOf` is not possible since it results in too
eager evaluation. In particular, the
home.sessionVariables = {
FOO = "Hello";
BAR = "${config.home.sessionVariables.FOO} World!";
};
example will cause an infinite recursion.
This commit restores the option type of
- `home.sessionVariables`,
- `pam.sessionVariables`,
- `programs.bash.sessionVariables`, and
- `programs.zsh.sessionVariables`
to `attrs`. It also adds test cases for the above options to avoid
regressions.
Fixes#659
