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