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use std::fmt::Display;
use std::fs;
use std::io::{Read, Write};
use std::path::Path;
/// A no-op struct that allows you to easily manipulate files.
pub struct File;
impl File {
/// Read a file at `path` into a String.
pub fn read<P: AsRef<Path>>(path: P) -> Result<String, String> {
let mut file = fs::OpenOptions::new().read(true).open(&path);
match &mut file {
Ok(f) => {
let mut contents = String::from("");
match f.read_to_string(&mut contents) {
Ok(_) => Ok(contents),
Err(e) => Err(format!(
"Could not read from file '{}' because {}",
match path.as_ref().to_str() {
Some(s) => s,
None => "",
},
e.to_string()
)),
}
}
Err(e) => Err(format!(
"Could not open file '{}' because {}",
match path.as_ref().to_str() {
Some(s) => s,
None => "",
},
e.to_string()
)),
}
}
/// Write a string to file.
/// This truncates a file (sets its size to zero to clear its contents),
/// and then writes `contents` to the file.
pub fn write<P: AsRef<Path>, S: Display>(path: P, contents: S) -> Result<(), String> {
let mut file = fs::OpenOptions::new()
.create(true)
.write(true)
.truncate(true)
.open(&path);
match &mut file {
Ok(f) => match writeln!(f, "{}", contents) {
Ok(_) => Ok(()),
Err(e) => Err(format!(
"Could not open file '{}' because {}",
match path.as_ref().to_str() {
Some(s) => s,
None => "",
},
e.to_string()
)),
},
Err(e) => Err(format!(
"Could not open file '{}' because {}",
match path.as_ref().to_str() {
Some(s) => s,
None => "",
},
e.to_string()
)),
}
}
/// This does the same as write, but does not wipe the file,
/// and appends `contents` to the end of the file.
pub fn append<P: AsRef<Path>, S: Display>(path: P, contents: S) -> Result<(), String> {
let mut file = fs::OpenOptions::new().append(true).write(true).open(&path);
match &mut file {
Ok(f) => match writeln!(f, "{}", contents) {
Ok(_) => Ok(()),
Err(e) => Err(format!(
"Could not open file '{}' because {}",
match path.as_ref().to_str() {
Some(s) => s,
None => "",
},
e.to_string()
)),
},
Err(e) => Err(format!(
"Could not open file '{}' because {}",
match path.as_ref().to_str() {
Some(s) => s,
None => "",
},
e.to_string()
)),
}
}
}