Crate fs_err

fs-err is a drop-in replacement for std::fs that provides more helpful messages on errors. Extra information includes which operations was attmpted and any involved paths.

Error Messages

Using std::fs, if this code fails:

let file = File::open("does not exist.txt")?;

The error message that Rust gives you isn't very useful:

The system cannot find the file specified. (os error 2)

...but if we use fs-err instead, our error contains more actionable information:

failed to open file `does not exist.txt`
    caused by: The system cannot find the file specified. (os error 2)

Usage

fs-err's API is the same as std::fs, so migrating code to use it is easy.

// use std::fs;
use fs_err as fs;

let contents = fs::read_to_string("foo.txt")?;

println!("Read foo.txt: {}", contents);

fs-err uses std::io::Error for all errors. This helps fs-err compose well with traits from the standard library like std::io::Read and crates that use them like serde_json:

use fs_err::File;

let file = File::open("my-config.json")?;

// If an I/O error occurs inside serde_json, the error will include a file path
// as well as what operation was being performed.
let decoded: Vec<String> = serde_json::from_reader(file)?;

println!("Program config: {:?}", decoded);

Modules

os	OS-specific functionality.

Structs

DirEntry	Wrapper around std::fs::DirEntry which adds more helpful information to all errors.
File	Wrapper around std::fs::File which adds more helpful information to all errors.
OpenOptions	Wrapper around std::fs::OptionOptions
ReadDir	Wrapper around std::fs::ReadDir which adds more helpful information to all errors.

Traits

PathExt

Defines aliases on Path for fs_err functions.

Functions

canonicalize	Wrapper for fs::canonicalize.
copy	Wrapper for fs::copy.
create_dir	Wrapper for fs::create_dir.
create_dir_all	Wrapper for fs::create_dir_all.
hard_link	Wrapper for fs::hard_link.
metadata	Wrapper for fs::metadata.
read	Wrapper for fs::read.
read_dir	Wrapper for fs::read_dir.
read_link	Wrapper for fs::read_link.
read_to_string	Wrapper for fs::read_to_string.
remove_dir	Wrapper for fs::remove_dir.
remove_dir_all	Wrapper for fs::remove_dir_all.
remove_file	Wrapper for fs::remove_file.
rename	Wrapper for fs::rename.
set_permissions	Wrapper for fs::set_permissions.
soft_link	Deprecated Wrapper for fs::soft_link.
symlink_metadata	Wrapper for fs::symlink_metadata.
write	Wrapper for fs::write.