Kivanc Gunalp 4e9b5735ad Use more idiomatic Rust in file_io2/file_io3
- file_io2: replace the manual line_number counter with
  .lines().enumerate(), and replace
  buffered_file_writer.write(format!(...).as_bytes()) with writeln!,
  which both formats and guarantees a complete write (write_fmt loops
  internally, unlike a single Write::write call).
- file_io3: replace the manual match on file_path.parent() with
  .ok_or_else(...)? for a more idiomatic Option-to-Result conversion.

Verified locally: both solutions compile under edition 2024, clippy is
silent, and running them still produces identical output (3 lines
processed / 117-byte file, non-readonly permissions) with no leftover
files.
2026-07-26 15:48:35 +00:00

78 lines
2.0 KiB
Rust

use std::fs;
use std::io::Error;
use std::path::PathBuf;
const SAMPLE_TEXT: &str = "This is the first line of the text.
This is the second line.
And this is the third and the last line.";
fn sample_file_path() -> PathBuf {
PathBuf::from("SampleFilesFolder/MultiLineTextFile.txt")
}
fn main() -> Result<(), std::io::Error> {
create_required_files()?;
let path_buffer = sample_file_path();
let meta_data_result = path_buffer.metadata();
match meta_data_result {
Ok(meta_data) => {
println!("Metadata about the file : {:?}", path_buffer);
println!("File creation time {:?}", meta_data.created());
println!("File size {}", meta_data.len());
assert_eq!(meta_data.len(), SAMPLE_TEXT.len() as u64);
println!("File permissions {:?}", meta_data.permissions());
assert!(!meta_data.permissions().readonly());
}
Err(error) => {
eprintln!("Could not get metadata. Error: {:?}", error);
}
}
file_cleanup()
}
fn create_required_files() -> Result<(), std::io::Error> {
let file_path = sample_file_path();
let dir_path = file_path
.parent()
.ok_or_else(|| Error::other("Could not get parent path"))?;
if !dir_path.exists() {
fs::create_dir_all(dir_path).inspect_err(|x| {
eprintln!("Could not create directory: {:?}", x);
})?;
}
if !file_path.exists() {
fs::write(&file_path, SAMPLE_TEXT).inspect_err(|err| {
eprintln!("Couldn't create test file: {:?}", err);
})?;
}
Ok(())
}
fn file_cleanup() -> Result<(), std::io::Error> {
let path_buffer = sample_file_path();
if path_buffer.exists() {
fs::remove_file(&path_buffer).inspect(|_| {
println!("Test file removed");
})?;
}
if let Some(dir_path) = path_buffer.parent()
&& dir_path.exists()
{
fs::remove_dir(dir_path).inspect(|_| {
println!("Test dir removed");
})?;
}
Ok(())
}