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, Mismatch};
  22 use checkstyle::{output_heading, output_footing, output_checkstyle_file};
  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<(), io::Error> {
  38     output_heading(mode).ok();
  39     for filename in file_map.keys() {
  40         try!(write_file(&file_map[filename], filename, mode, config));
  41     }
  42     output_footing(mode).ok();
  43
  44     Ok(())
  45 }
  46
  47
  48 // Prints all newlines either as `\n` or as `\r\n`.
  49 pub fn write_system_newlines<T>(writer: T,
  50                                 text: &StringBuffer,
  51                                 config: &Config)
  52                                 -> Result<(), io::Error>
  53     where T: Write
  54 {
  55     // Buffer output, since we're writing a since char at a time.
  56     let mut writer = BufWriter::new(writer);
  57
  58     let style = if config.newline_style == NewlineStyle::Native {
  59         if cfg!(windows) {
  60             NewlineStyle::Windows
  61         } else {
  62             NewlineStyle::Unix
  63         }
  64     } else {
  65         config.newline_style
  66     };
  67
  68     match style {
  69         NewlineStyle::Unix => write!(writer, "{}", text),
  70         NewlineStyle::Windows => {
  71             for (c, _) in text.chars() {
  72                 match c {
  73                     '\n' => try!(write!(writer, "\r\n")),
  74                     '\r' => continue,
  75                     c => try!(write!(writer, "{}", c)),
  76                 }
  77             }
  78             Ok(())
  79         }
  80         NewlineStyle::Native => unreachable!(),
  81     }
  82 }
  83
  84 pub fn write_file(text: &StringBuffer,
  85                   filename: &str,
  86                   mode: WriteMode,
  87                   config: &Config)
  88                   -> Result<Option<String>, io::Error> {
  89
  90     fn source_and_formatted_text(text: &StringBuffer,
  91                                  filename: &str,
  92                                  config: &Config)
  93                                  -> Result<(String, String), io::Error> {
  94         let mut f = try!(File::open(filename));
  95         let mut ori_text = String::new();
  96         try!(f.read_to_string(&mut ori_text));
  97         let mut v = Vec::new();
  98         try!(write_system_newlines(&mut v, text, config));
  99         let fmt_text = String::from_utf8(v).unwrap();
 100         Ok((ori_text, fmt_text))
 101     }
 102
 103     fn create_diff(filename: &str,
 104                    text: &StringBuffer,
 105                    config: &Config)
 106                    -> Result<Vec<Mismatch>, io::Error> {
 107         let (ori, fmt) = try!(source_and_formatted_text(text, filename, config));
 108         Ok(make_diff(&ori, &fmt, 3))
 109     }
 110
 111     match mode {
 112         WriteMode::Replace => {
 113             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 114                 if fmt != ori {
 115                     // Do a little dance to make writing safer - write to a temp file
 116                     // rename the original to a .bk, then rename the temp file to the
 117                     // original.
 118                     let tmp_name = filename.to_owned() + ".tmp";
 119                     let bk_name = filename.to_owned() + ".bk";
 120                     {
 121                         // Write text to temp file
 122                         let tmp_file = try!(File::create(&tmp_name));
 123                         try!(write_system_newlines(tmp_file, text, config));
 124                     }
 125
 126                     try!(fs::rename(filename, bk_name));
 127                     try!(fs::rename(tmp_name, filename));
 128                 }
 129             }
 130         }
 131         WriteMode::Overwrite => {
 132             // Write text directly over original file.
 133             let file = try!(File::create(filename));
 134             try!(write_system_newlines(file, text, config));
 135         }
 136         WriteMode::Plain => {
 137             let stdout = stdout();
 138             let stdout = stdout.lock();
 139             try!(write_system_newlines(stdout, text, config));
 140         }
 141         WriteMode::Display | WriteMode::Coverage => {
 142             println!("{}:\n", filename);
 143             let stdout = stdout();
 144             let stdout = stdout.lock();
 145             try!(write_system_newlines(stdout, text, config));
 146         }
 147         WriteMode::Diff => {
 148             println!("Diff of {}:\n", filename);
 149             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 150                 print_diff(make_diff(&ori, &fmt, 3),
 151                            |line_num| format!("\nDiff at line {}:", line_num));
 152             }
 153         }
 154         WriteMode::Default => {
 155             unreachable!("The WriteMode should NEVER Be default at this point!");
 156         }
 157         WriteMode::Checkstyle => {
 158             let stdout = stdout();
 159             let stdout = stdout.lock();
 160             let diff = try!(create_diff(filename, text, config));
 161             // Output the XML tags for the lines that are different.
 162             try!(output_checkstyle_file(stdout, filename, diff));
 163         }
 164         WriteMode::Return => {
 165             // io::Write is not implemented for String, working around with
 166             // Vec<u8>
 167             let mut v = Vec::new();
 168             try!(write_system_newlines(&mut v, text, config));
 169             // won't panic, we are writing correct utf8
 170             return Ok(Some(String::from_utf8(v).unwrap()));
 171         }
 172     }
 173
 174     Ok(None)
 175 }