Trait Fs 

pub trait Fs {
    // Required methods
    fn create_dir_all(&self, path: &Path) -> Result<(), SessionError>;
    fn exists(&self, path: &Path) -> bool;
    fn read(&self, path: &Path) -> Result<Vec<u8>, SessionError>;
    fn write(&self, path: &Path, data: &[u8]) -> Result<(), SessionError>;
    fn append(&self, path: &Path, data: &[u8]) -> Result<(), SessionError>;
    fn read_dir(&self, path: &Path) -> Result<Vec<PathBuf>, SessionError>;
    fn rename(&self, from: &Path, to: &Path) -> Result<(), SessionError>;
    fn remove(&self, path: &Path) -> Result<(), SessionError>;
}

Abstraction over filesystem operations used by zenith-session.

Implementations must satisfy the following contract:

• All directory and file listings are returned sorted for deterministic iteration across platforms.
• write must fail with an error when the parent directory does not exist (to faithfully model real OS behaviour so fakes don’t silently false-pass tests that forget create_dir_all).

Required Methods

fn create_dir_all(&self, path: &Path) -> Result<(), SessionError>

Create path and all missing ancestors, like mkdir -p.

fn exists(&self, path: &Path) -> bool

Return true if path exists (file or directory).

fn read(&self, path: &Path) -> Result<Vec<u8>, SessionError>

Read the entire contents of the file at path.

fn write(&self, path: &Path, data: &[u8]) -> Result<(), SessionError>

Write data to path, replacing any existing content.

Returns an error if the parent directory does not exist.

fn append(&self, path: &Path, data: &[u8]) -> Result<(), SessionError>

Append data to the file at path, creating it if absent. Like write, it errors if the parent directory does not exist.

fn read_dir(&self, path: &Path) -> Result<Vec<PathBuf>, SessionError>

List immediate children (files and directories) of path, sorted for deterministic iteration.

fn rename(&self, from: &Path, to: &Path) -> Result<(), SessionError>

Rename / move from to to.

fn remove(&self, path: &Path) -> Result<(), SessionError>

Remove a file or directory tree at path.

Tries remove_file first; on failure tries remove_dir_all. This keeps the API simple: callers do not need to know whether path is a file or a directory.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl Fs for MemFs

impl Fs for OsFs