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 pub 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         let style = if config.newline_style == NewlineStyle::Native {
  63             if cfg!(windows) {
  64                 NewlineStyle::Windows
  65             } else {
  66                 NewlineStyle::Unix
  67             }
  68         } else {
  69             config.newline_style
  70         };
  71
  72         match style {
  73             NewlineStyle::Unix => write!(writer, "{}", text),
  74             NewlineStyle::Windows => {
  75                 for (c, _) in text.chars() {
  76                     match c {
  77                         '\n' => try!(write!(writer, "\r\n")),
  78                         '\r' => continue,
  79                         c => try!(write!(writer, "{}", c)),
  80                     }
  81                 }
  82                 Ok(())
  83             }
  84             NewlineStyle::Native => unreachable!(),
  85         }
  86     }
  87
  88     fn source_and_formatted_text(text: &StringBuffer,
  89                                  filename: &str,
  90                                  config: &Config)
  91                                  -> Result<(String, String), io::Error> {
  92         let mut f = try!(File::open(filename));
  93         let mut ori_text = String::new();
  94         try!(f.read_to_string(&mut ori_text));
  95         let mut v = Vec::new();
  96         try!(write_system_newlines(&mut v, text, config));
  97         let fmt_text = String::from_utf8(v).unwrap();
  98         Ok((ori_text, fmt_text))
  99     }
 100
 101     match mode {
 102         WriteMode::Replace => {
 103             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 104                 if fmt != ori {
 105                     // Do a little dance to make writing safer - write to a temp file
 106                     // rename the original to a .bk, then rename the temp file to the
 107                     // original.
 108                     let tmp_name = filename.to_owned() + ".tmp";
 109                     let bk_name = filename.to_owned() + ".bk";
 110                     {
 111                         // Write text to temp file
 112                         let tmp_file = try!(File::create(&tmp_name));
 113                         try!(write_system_newlines(tmp_file, text, config));
 114                     }
 115
 116                     try!(fs::rename(filename, bk_name));
 117                     try!(fs::rename(tmp_name, filename));
 118                 }
 119             }
 120         }
 121         WriteMode::Overwrite => {
 122             // Write text directly over original file.
 123             let file = try!(File::create(filename));
 124             try!(write_system_newlines(file, text, config));
 125         }
 126         WriteMode::NewFile(extn) => {
 127             let filename = filename.to_owned() + "." + extn;
 128             let file = try!(File::create(&filename));
 129             try!(write_system_newlines(file, text, config));
 130         }
 131         WriteMode::Plain => {
 132             let stdout = stdout();
 133             let stdout = stdout.lock();
 134             try!(write_system_newlines(stdout, text, config));
 135         }
 136         WriteMode::Display | WriteMode::Coverage => {
 137             println!("{}:\n", filename);
 138             let stdout = stdout();
 139             let stdout = stdout.lock();
 140             try!(write_system_newlines(stdout, text, config));
 141         }
 142         WriteMode::Diff => {
 143             println!("Diff of {}:\n", filename);
 144             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 145                 print_diff(make_diff(&ori, &fmt, 3),
 146                            |line_num| format!("\nDiff at line {}:", line_num));
 147             }
 148         }
 149         WriteMode::Return => {
 150             // io::Write is not implemented for String, working around with
 151             // Vec<u8>
 152             let mut v = Vec::new();
 153             try!(write_system_newlines(&mut v, text, config));
 154             // won't panic, we are writing correct utf8
 155             return Ok(Some(String::from_utf8(v).unwrap()));
 156         }
 157     }
 158
 159     Ok(None)
 160 }