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::fs::{self, File};
  17 use std::io::{self, Write, Read, BufWriter};
  18
  19 use config::{NewlineStyle, Config, WriteMode};
  20 use rustfmt_diff::{make_diff, print_diff, Mismatch};
  21 use checkstyle::{output_header, output_footer, output_checkstyle_file};
  22
  23 // A map of the files of a crate, with their new content
  24 pub type FileMap = Vec<FileRecord>;
  25
  26 pub type FileRecord = (String, StringBuffer);
  27
  28 // Append a newline to the end of each file.
  29 pub fn append_newline(s: &mut StringBuffer) {
  30     s.push_str("\n");
  31 }
  32
  33 pub fn write_all_files<T>(file_map: &FileMap, out: &mut T, config: &Config) -> Result<(), io::Error>
  34     where T: Write
  35 {
  36     output_header(out, config.write_mode()).ok();
  37     for &(ref filename, ref text) in file_map {
  38         write_file(text, filename, out, config)?;
  39     }
  40     output_footer(out, config.write_mode()).ok();
  41
  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' => write!(writer, "\r\n")?,
  71                     '\r' => continue,
  72                     c => write!(writer, "{}", c)?,
  73                 }
  74             }
  75             Ok(())
  76         }
  77         NewlineStyle::Native => unreachable!(),
  78     }
  79 }
  80
  81 pub fn write_file<T>(text: &StringBuffer,
  82                      filename: &str,
  83                      out: &mut T,
  84                      config: &Config)
  85                      -> Result<bool, io::Error>
  86     where T: Write
  87 {
  88
  89     fn source_and_formatted_text(text: &StringBuffer,
  90                                  filename: &str,
  91                                  config: &Config)
  92                                  -> Result<(String, String), io::Error> {
  93         let mut f = File::open(filename)?;
  94         let mut ori_text = String::new();
  95         f.read_to_string(&mut ori_text)?;
  96         let mut v = Vec::new();
  97         write_system_newlines(&mut v, text, config)?;
  98         let fmt_text = String::from_utf8(v).unwrap();
  99         Ok((ori_text, fmt_text))
 100     }
 101
 102     fn create_diff(filename: &str,
 103                    text: &StringBuffer,
 104                    config: &Config)
 105                    -> Result<Vec<Mismatch>, io::Error> {
 106         let (ori, fmt) = source_and_formatted_text(text, filename, config)?;
 107         Ok(make_diff(&ori, &fmt, 3))
 108     }
 109
 110     match config.write_mode() {
 111         WriteMode::Replace => {
 112             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 113                 if fmt != ori {
 114                     // Do a little dance to make writing safer - write to a temp file
 115                     // rename the original to a .bk, then rename the temp file to the
 116                     // original.
 117                     let tmp_name = filename.to_owned() + ".tmp";
 118                     let bk_name = filename.to_owned() + ".bk";
 119                     {
 120                         // Write text to temp file
 121                         let tmp_file = File::create(&tmp_name)?;
 122                         write_system_newlines(tmp_file, text, config)?;
 123                     }
 124
 125                     fs::rename(filename, bk_name)?;
 126                     fs::rename(tmp_name, filename)?;
 127                 }
 128             }
 129         }
 130         WriteMode::Overwrite => {
 131             // Write text directly over original file.
 132             let file = File::create(filename)?;
 133             write_system_newlines(file, text, config)?;
 134         }
 135         WriteMode::Plain => {
 136             write_system_newlines(out, text, config)?;
 137         }
 138         WriteMode::Display | WriteMode::Coverage => {
 139             println!("{}:\n", filename);
 140             write_system_newlines(out, text, config)?;
 141         }
 142         WriteMode::Diff => {
 143             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 144                 let mismatch = make_diff(&ori, &fmt, 3);
 145                 let has_diff = !mismatch.is_empty();
 146                 print_diff(mismatch,
 147                            |line_num| format!("Diff in {} at line {}:", filename, line_num));
 148                 return Ok(has_diff);
 149             }
 150         }
 151         WriteMode::Checkstyle => {
 152             let diff = create_diff(filename, text, config)?;
 153             output_checkstyle_file(out, filename, diff)?;
 154         }
 155     }
 156
 157     // when we are not in diff mode, don't indicate differing files
 158     Ok(false)
 159 }