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
  35     T: Write,
  36 {
  37     output_header(out, config.write_mode()).ok();
  38     for &(ref filename, ref text) in file_map {
  39         write_file(text, filename, out, config)?;
  40     }
  41     output_footer(out, config.write_mode()).ok();
  42
  43     Ok(())
  44 }
  45
  46 // Prints all newlines either as `\n` or as `\r\n`.
  47 pub fn write_system_newlines<T>(
  48     writer: T,
  49     text: &StringBuffer,
  50     config: &Config,
  51 ) -> Result<(), io::Error>
  52 where
  53     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' => write!(writer, "\r\n")?,
  74                     '\r' => continue,
  75                     c => write!(writer, "{}", c)?,
  76                 }
  77             }
  78             Ok(())
  79         }
  80         NewlineStyle::Native => unreachable!(),
  81     }
  82 }
  83
  84 pub fn write_file<T>(
  85     text: &StringBuffer,
  86     filename: &str,
  87     out: &mut T,
  88     config: &Config,
  89 ) -> Result<bool, io::Error>
  90 where
  91     T: Write,
  92 {
  93
  94     fn source_and_formatted_text(
  95         text: &StringBuffer,
  96         filename: &str,
  97         config: &Config,
  98     ) -> Result<(String, String), io::Error> {
  99         let mut f = File::open(filename)?;
 100         let mut ori_text = String::new();
 101         f.read_to_string(&mut ori_text)?;
 102         let mut v = Vec::new();
 103         write_system_newlines(&mut v, text, config)?;
 104         let fmt_text = String::from_utf8(v).unwrap();
 105         Ok((ori_text, fmt_text))
 106     }
 107
 108     fn create_diff(
 109         filename: &str,
 110         text: &StringBuffer,
 111         config: &Config,
 112     ) -> Result<Vec<Mismatch>, io::Error> {
 113         let (ori, fmt) = source_and_formatted_text(text, filename, config)?;
 114         Ok(make_diff(&ori, &fmt, 3))
 115     }
 116
 117     match config.write_mode() {
 118         WriteMode::Replace => {
 119             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 120                 if fmt != ori {
 121                     // Do a little dance to make writing safer - write to a temp file
 122                     // rename the original to a .bk, then rename the temp file to the
 123                     // original.
 124                     let tmp_name = filename.to_owned() + ".tmp";
 125                     let bk_name = filename.to_owned() + ".bk";
 126                     {
 127                         // Write text to temp file
 128                         let tmp_file = File::create(&tmp_name)?;
 129                         write_system_newlines(tmp_file, text, config)?;
 130                     }
 131
 132                     fs::rename(filename, bk_name)?;
 133                     fs::rename(tmp_name, filename)?;
 134                 }
 135             }
 136         }
 137         WriteMode::Overwrite => {
 138             // Write text directly over original file if there is a diff.
 139             let (source, formatted) = source_and_formatted_text(text, filename, config)?;
 140             if source != formatted {
 141                 let file = File::create(filename)?;
 142                 write_system_newlines(file, text, config)?;
 143             }
 144         }
 145         WriteMode::Plain => {
 146             write_system_newlines(out, text, config)?;
 147         }
 148         WriteMode::Display | WriteMode::Coverage => {
 149             println!("{}:\n", filename);
 150             write_system_newlines(out, text, config)?;
 151         }
 152         WriteMode::Diff => {
 153             if let Ok((ori, fmt)) = source_and_formatted_text(text, filename, config) {
 154                 let mismatch = make_diff(&ori, &fmt, 3);
 155                 let has_diff = !mismatch.is_empty();
 156                 print_diff(mismatch, |line_num| {
 157                     format!("Diff in {} at line {}:", filename, line_num)
 158                 });
 159                 return Ok(has_diff);
 160             }
 161         }
 162         WriteMode::Checkstyle => {
 163             let diff = create_diff(filename, text, config)?;
 164             output_checkstyle_file(out, filename, diff)?;
 165         }
 166     }
 167
 168     // when we are not in diff mode, don't indicate differing files
 169     Ok(false)
 170 }