tools/src/oswrapper/oswrapper.go

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// Package oswrapper provides interfaces for the built-in os and filepath packages.
// This facilitates better testing via dependency injection.
package oswrapper

import (
	"os"
	"path/filepath"

	"github.com/spf13/afero"
)

// OSWrapper is a wrapper around all filesystem and environment-related os functions.
type OSWrapper interface {
	EnvironProvider
	FilesystemReaderWriter
}

// EnvironProvider is a wrapper around environment-related os functions.
type EnvironProvider interface {
	Environ() []string
	Getenv(key string) string
	Getwd() (string, error)
	UserHomeDir() (string, error)
}

// FilesystemReaderWriter is a wrapper around read and write-related filesystem os functions.
type FilesystemReaderWriter interface {
	FilesystemReader
	FilesystemWriter
}

// FilesystemReader is a wrapper around the read-related filesystem os functions.
type FilesystemReader interface {
	Open(name string) (afero.File, error)
	OpenFile(name string, flag int, perm os.FileMode) (afero.File, error)
	ReadFile(name string) ([]byte, error)
	Stat(name string) (os.FileInfo, error)
	Walk(root string, fn filepath.WalkFunc) error
}

// FilesystemWriter is a wrapper around the read-related filesystem os functions.
type FilesystemWriter interface {
	Create(name string) (afero.File, error)
	Mkdir(path string, perm os.FileMode) error
	MkdirAll(path string, perm os.FileMode) error
	MkdirTemp(dir, pattern string) (string, error)
	Remove(name string) error
	RemoveAll(path string) error
	Symlink(oldname, newname string) error
	WriteFile(name string, data []byte, perm os.FileMode) error
}