src/doc/reference/stable-check/src/main.rs

   1 use std::error::Error;
   2 use std::env;
   3 use std::fs;
   4 use std::fs::File;
   5 use std::io::prelude::*;
   6 use std::path::Path;
   7
   8 fn main() {
   9     let arg = env::args().nth(1).unwrap_or_else(|| {
  10         println!("Please pass a src directory as the first argument");
  11         std::process::exit(1);
  12     });
  13
  14     match check_directory(&Path::new(&arg)) {
  15         Ok(()) => println!("passed!"),
  16         Err(e) => {
  17             println!("Error: {}", e);
  18             std::process::exit(1);
  19         }
  20     }
  21 }
  22
  23 fn check_directory(dir: &Path) -> Result<(), Box<dyn Error>> {
  24     for entry in fs::read_dir(dir)? {
  25         let entry = entry?;
  26         let path = entry.path();
  27
  28         if path.is_dir() {
  29             return check_directory(&path);
  30         }
  31
  32         let mut file = File::open(&path)?;
  33         let mut contents = String::new();
  34         file.read_to_string(&mut contents)?;
  35
  36         if contents.contains("#![feature") {
  37             return Err(From::from(format!("Feature flag found in {:?}", path)));
  38         }
  39     }
  40
  41     Ok(())
  42 }