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)
Modernize the codebase to use idiomatic Go 1.25 patterns, removing deprecated APIs and reducing external dependencies.
- Replace deprecated `io/ioutil` with `os.ReadFile`, `os.WriteFile`, `os.MkdirTemp`, `os.CreateTemp`
- Replace `interface{}` with `any` (Go 1.18+)
- Remove `github.com/pkg/errors` dependency entirely, using stdlib `fmt.Errorf` with `%w` and `errors.New`
- Use `errors.As()` instead of direct type assertions on error values
- Use `strings.Cut()` for delimiter parsing instead of `strings.Split` + length check
- Use `slices.Contains()` for linear search in `ContextExists()`
- Use `t.Setenv()` and `t.TempDir()` in tests instead of manual env save/restore and temp dir cleanup
- Delete unused `internal/testutil/tempfile.go` helper
- Update GitHub Actions CI and release workflows from Go 1.22 to 1.25
Net result: -70 lines, 1 fewer external dependency.
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
For windows, if the ctx name for kubens state file
contains a colon ':' (EKS), we replace it with __ (both while reading/writing).
It doesn't break existing users (as it didn't work in the first place).
Other characters remain unhandled, hoping it won't happen again.
Signed-off-by: Ahmet Alp Balkan <ahmetb@google.com>
