t.Setenv is the modern standard Go testing utility (since Go 1.17) that automatically restores environment variables when the test completes. This replaces the custom testutil.WithEnvVar function which manually saved and restored env var state.
The testutil.go file is deleted as it only contained WithEnvVar. The testutil package remains for its other utilities like KubeconfigBuilder.
Adds a new CacheDir() function that respects the XDG_CACHE_HOME environment variable,
matching the bash scripts' behavior. kubectx and kubens now prefer XDG_CACHE_HOME when
set, falling back to $HOME/.kube otherwise. This aligns the Go implementations with
the bash scripts' cache directory logic.
Includes comprehensive tests covering all scenarios:
- XDG_CACHE_HOME set (returns the XDG value)
- XDG_CACHE_HOME unset (falls back to $HOME/.kube)
- Neither set (returns empty string)
* stop using XDG_CACHE_HOME as home directory
XDG_CACHE_HOME is not a substitute for $HOME, see [1].
[1]: https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
* fix bats testing setup/teardown
since cmdutil.Homedir() would treat $XDG_CACHE_HOME as $HOME, deleting
$XDG_CACHE_HOME would wipe out previous kubens state. now that we're not
doing that, we need to make a real synthetic $HOME and clear it out so
that $HOME/.kube/kubens doesn't persist between runs.
