src/source_file.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 use std::fs;
  12 use std::io::{self, Write};
  13
  14 use checkstyle::output_checkstyle_file;
  15 use config::{Config, EmitMode, FileName, Verbosity};
  16 use rustfmt_diff::{make_diff, output_modified, print_diff};
  17
  18 #[cfg(test)]
  19 use formatting::FileRecord;
  20
  21 // Append a newline to the end of each file.
  22 pub fn append_newline(s: &mut String) {
  23     s.push_str("\n");
  24 }
  25
  26 #[cfg(test)]
  27 pub(crate) fn write_all_files<T>(
  28     source_file: &[FileRecord],
  29     out: &mut T,
  30     config: &Config,
  31 ) -> Result<(), io::Error>
  32 where
  33     T: Write,
  34 {
  35     if config.emit_mode() == EmitMode::Checkstyle {
  36         write!(out, "{}", ::checkstyle::header())?;
  37     }
  38     for &(ref filename, ref text) in source_file {
  39         write_file(text, filename, out, config)?;
  40     }
  41     if config.emit_mode() == EmitMode::Checkstyle {
  42         write!(out, "{}", ::checkstyle::footer())?;
  43     }
  44
  45     Ok(())
  46 }
  47
  48 pub fn write_file<T>(
  49     formatted_text: &str,
  50     filename: &FileName,
  51     out: &mut T,
  52     config: &Config,
  53 ) -> Result<bool, io::Error>
  54 where
  55     T: Write,
  56 {
  57     let filename_to_path = || match *filename {
  58         FileName::Real(ref path) => path,
  59         _ => panic!("cannot format `{}` and emit to files", filename),
  60     };
  61
  62     match config.emit_mode() {
  63         EmitMode::Files if config.make_backup() => {
  64             let filename = filename_to_path();
  65             let ori = fs::read_to_string(filename)?;
  66             if ori != formatted_text {
  67                 // Do a little dance to make writing safer - write to a temp file
  68                 // rename the original to a .bk, then rename the temp file to the
  69                 // original.
  70                 let tmp_name = filename.with_extension("tmp");
  71                 let bk_name = filename.with_extension("bk");
  72
  73                 fs::write(&tmp_name, formatted_text)?;
  74                 fs::rename(filename, bk_name)?;
  75                 fs::rename(tmp_name, filename)?;
  76             }
  77         }
  78         EmitMode::Files => {
  79             // Write text directly over original file if there is a diff.
  80             let filename = filename_to_path();
  81             let ori = fs::read_to_string(filename)?;
  82             if ori != formatted_text {
  83                 fs::write(filename, formatted_text)?;
  84             }
  85         }
  86         EmitMode::Stdout | EmitMode::Coverage => {
  87             if config.verbose() != Verbosity::Quiet {
  88                 println!("{}:\n", filename);
  89             }
  90             write!(out, "{}", formatted_text)?;
  91         }
  92         EmitMode::ModifiedLines => {
  93             let filename = filename_to_path();
  94             let ori = fs::read_to_string(filename)?;
  95             let mismatch = make_diff(&ori, formatted_text, 0);
  96             let has_diff = !mismatch.is_empty();
  97             output_modified(out, mismatch);
  98             return Ok(has_diff);
  99         }
 100         EmitMode::Checkstyle => {
 101             let filename = filename_to_path();
 102             let ori = fs::read_to_string(filename)?;
 103             let diff = make_diff(&ori, formatted_text, 3);
 104             output_checkstyle_file(out, filename, diff)?;
 105         }
 106         EmitMode::Diff => {
 107             let filename = filename_to_path();
 108             let ori = fs::read_to_string(filename)?;
 109             let mismatch = make_diff(&ori, formatted_text, 3);
 110             let has_diff = !mismatch.is_empty();
 111             print_diff(
 112                 mismatch,
 113                 |line_num| format!("Diff in {} at line {}:", filename.display(), line_num),
 114                 config,
 115             );
 116             return Ok(has_diff);
 117         }
 118     }
 119
 120     // when we are not in diff mode, don't indicate differing files
 121     Ok(false)
 122 }