src/filemap.rs

   1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11
  12 // TODO: add tests
  13
  14 use strings::string_buffer::StringBuffer;
  15
  16 use std::collections::HashMap;
  17 use std::fs::{self, File};
  18 use std::io::{self, Write, Read, stdout};
  19
  20 use WriteMode;
  21 use config::{NewlineStyle, Config};
  22 use rustfmt_diff::{make_diff, print_diff};
  23
  24 // A map of the files of a crate, with their new content
  25 pub type FileMap = HashMap<String, StringBuffer>;
  26
  27 // Append a newline to the end of each file.
  28 pub fn append_newlines(file_map: &mut FileMap) {
  29     for (_, s) in file_map.iter_mut() {
  30         s.push_str("\n");
  31     }
  32 }
  33
  34 pub fn write_all_files(file_map: &FileMap,
  35                        mode: WriteMode,
  36                        config: &Config)
  37                        -> Result<(HashMap<String, String>), io::Error> {
  38     let mut result = HashMap::new();
  39     for filename in file_map.keys() {
  40         let one_result = try!(write_file(&file_map[filename], filename, mode, config));
  41         if let Some(r) = one_result {
  42             result.insert(filename.clone(), r);
  43         }
  44     }
  45
  46     Ok(result)
  47 }
  48
  49 fn write_file(text: &StringBuffer,
  50               filename: &str,
  51               mode: WriteMode,
  52               config: &Config)
  53               -> Result<Option<String>, io::Error> {
  54
  55     // prints all newlines either as `\n` or as `\r\n`
  56     fn write_system_newlines<T>(mut writer: T,
  57                                 text: &StringBuffer,
  58                                 config: &Config)
  59                                 -> Result<(), io::Error>
  60         where T: Write
  61     {
  62         match config.newline_style {
  63             NewlineStyle::Unix => write!(writer, "{}", text),
  64             NewlineStyle::Windows => {
  65                 for (c, _) in text.chars() {
  66                     match c {
  67                         '\n' => try!(write!(writer, "\r\n")),
  68                         '\r' => continue,
  69                         c => try!(write!(writer, "{}", c)),
  70                     }
  71                 }
  72                 Ok(())
  73             }
  74         }
  75     }
  76
  77     match mode {
  78         WriteMode::Replace => {
  79             // Do a little dance to make writing safer - write to a temp file
  80             // rename the original to a .bk, then rename the temp file to the
  81             // original.
  82             let tmp_name = filename.to_owned() + ".tmp";
  83             let bk_name = filename.to_owned() + ".bk";
  84             {
  85                 // Write text to temp file
  86                 let tmp_file = try!(File::create(&tmp_name));
  87                 try!(write_system_newlines(tmp_file, text, config));
  88             }
  89
  90             try!(fs::rename(filename, bk_name));
  91             try!(fs::rename(tmp_name, filename));
  92         }
  93         WriteMode::Overwrite => {
  94             // Write text directly over original file.
  95             let file = try!(File::create(filename));
  96             try!(write_system_newlines(file, text, config));
  97         }
  98         WriteMode::NewFile(extn) => {
  99             let filename = filename.to_owned() + "." + extn;
 100             let file = try!(File::create(&filename));
 101             try!(write_system_newlines(file, text, config));
 102         }
 103         WriteMode::Display => {
 104             println!("{}:\n", filename);
 105             let stdout = stdout();
 106             let stdout_lock = stdout.lock();
 107             try!(write_system_newlines(stdout_lock, text, config));
 108         }
 109         WriteMode::Diff => {
 110             println!("Diff of {}:\n", filename);
 111             let mut f = try!(File::open(filename));
 112             let mut ori_text = String::new();
 113             try!(f.read_to_string(&mut ori_text));
 114             let mut v = Vec::new();
 115             try!(write_system_newlines(&mut v, text, config));
 116             let fmt_text = String::from_utf8(v).unwrap();
 117             let diff = make_diff(&ori_text, &fmt_text, 3);
 118             print_diff(diff,
 119                        |line_num| format!("\nDiff at line {}:", line_num));
 120         }
 121         WriteMode::Return => {
 122             // io::Write is not implemented for String, working around with
 123             // Vec<u8>
 124             let mut v = Vec::new();
 125             try!(write_system_newlines(&mut v, text, config));
 126             // won't panic, we are writing correct utf8
 127             return Ok(Some(String::from_utf8(v).unwrap()));
 128         }
 129     }
 130
 131     Ok(None)
 132 }