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"
)

// 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) (*os.File, error)
	OpenFile(name string, flag int, perm os.FileMode) (*os.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) (*os.File, 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
}