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, BufWriter};
  19
  20 use config::{NewlineStyle, Config, WriteMode};
  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<(), io::Error> {
  37     for filename in file_map.keys() {
  38         try!(write_file(&file_map[filename], filename, mode, config));
  39     }
  40
  41     // Output trailers for write mode.
  42     Ok(())
  43 }
  44
  45 // Prints all newlines either as `\n` or as `\r\n`.
  46 pub fn write_system_newlines<T>(writer: T,
  47                                 text: &StringBuffer,
  48                                 config: &Config)
  49                                 -> Result<(), io::Error>
  50     where T: Write
  51 {
  52     // Buffer output, since we're writing a since char at a time.
  53     let mut writer = BufWriter::new(writer);
  54
  55     let style = if config.newline_style == NewlineStyle::Native {
  56         if cfg!(windows) {
  57             NewlineStyle::Windows
  58         } else {
  59             NewlineStyle::Unix
  60         }
  61     } else {
  62         config.newline_style
  63     };
  64
  65     match style {
  66         NewlineStyle::Unix => write!(writer, "{}", text),
  67         NewlineStyle::Windows => {
  68             for (c, _) in text.chars() {
  69                 match c {
  70                     '\n' => try!(write!(writer, "\r\n")),
  71                     '\r' => continue,
  72                     c => try!(write!(writer, "{}", c)),
  73                 }
  74             }
  75             Ok(())
  76         }
  77         NewlineStyle::Native => unreachable!(),
  78     }
  79 }
  80
  81 pub fn write_file(text: &StringBuffer,
  82                   filename: &str,
  83                   mode: WriteMode,
  84                   config: &Config)
  85                   -> Result<Option<String>, io::Error> {
  86
  87     fn source_and_formatted_text(text: &StringBuffer,
  88                                  filename: &str,
  89                                  config: &Config)
  90                                  -> Result<(String, String), io::Error> {
  91         let mut f = try!(File::open(filename));
  92         let mut ori_text = String::new();
  93         try!(f.read_to_string(&mut ori_text));
  94         let mut v = Vec::new();
  95         try!(write_system_newlines(&mut v, text, config));
  96         let fmt_text = String::from_utf8(v).unwrap();
  97         Ok((ori_text, fmt_text))
  98     }
  99
 100     match mode {
 101         WriteMode::Replace => {
 102             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 103                 if fmt != ori {
 104                     // Do a little dance to make writing safer - write to a temp file
 105                     // rename the original to a .bk, then rename the temp file to the
 106                     // original.
 107                     let tmp_name = filename.to_owned() + ".tmp";
 108                     let bk_name = filename.to_owned() + ".bk";
 109                     {
 110                         // Write text to temp file
 111                         let tmp_file = try!(File::create(&tmp_name));
 112                         try!(write_system_newlines(tmp_file, text, config));
 113                     }
 114
 115                     try!(fs::rename(filename, bk_name));
 116                     try!(fs::rename(tmp_name, filename));
 117                 }
 118             }
 119         }
 120         WriteMode::Overwrite => {
 121             // Write text directly over original file.
 122             let file = try!(File::create(filename));
 123             try!(write_system_newlines(file, text, config));
 124         }
 125         WriteMode::Plain => {
 126             let stdout = stdout();
 127             let stdout = stdout.lock();
 128             try!(write_system_newlines(stdout, text, config));
 129         }
 130         WriteMode::Display | WriteMode::Coverage => {
 131             println!("{}:\n", filename);
 132             let stdout = stdout();
 133             let stdout = stdout.lock();
 134             try!(write_system_newlines(stdout, text, config));
 135         }
 136         WriteMode::Diff => {
 137             println!("Diff of {}:\n", filename);
 138             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 139                 print_diff(make_diff(&ori, &fmt, 3),
 140                            |line_num| format!("\nDiff at line {}:", line_num));
 141             }
 142         }
 143         WriteMode::Default => {
 144             unreachable!("The WriteMode should NEVER Be default at this point!");
 145         }
 146         WriteMode::Checkstyle => {
 147             // Generate the diff for the current file.
 148             // Output the XML tags for the lines that are different.
 149             // Use the new text as 'should be X'.
 150         }
 151         WriteMode::Return => {
 152             // io::Write is not implemented for String, working around with
 153             // Vec<u8>
 154             let mut v = Vec::new();
 155             try!(write_system_newlines(&mut v, text, config));
 156             // won't panic, we are writing correct utf8
 157             return Ok(Some(String::from_utf8(v).unwrap()));
 158         }
 159     }
 160
 161     Ok(None)
 162 }