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.
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.
16 use strings::string_buffer::StringBuffer;
17 use std::collections::HashMap;
18 use syntax::codemap::{CodeMap, Span, BytePos};
24 // This is basically a wrapper around a bunch of Ropes which makes it convenient
25 // to work with libsyntax. It is badly named.
26 pub struct ChangeSet<'a> {
27 file_map: HashMap<String, StringBuffer>,
29 file_spans: Vec<(u32, u32)>,
32 impl<'a> ChangeSet<'a> {
33 // Create a new ChangeSet for a given libsyntax CodeMap.
34 pub fn from_codemap(codemap: &'a CodeMap) -> ChangeSet<'a> {
35 let mut result = ChangeSet {
36 file_map: HashMap::new(),
38 file_spans: Vec::with_capacity(codemap.files.borrow().len()),
41 for f in codemap.files.borrow().iter() {
42 // Use the length of the file as a heuristic for how much space we
43 // need. I hope that at some stage someone rounds this up to the next
44 // power of two. TODO check that or do it here.
45 result.file_map.insert(f.name.clone(),
46 StringBuffer::with_capacity(f.src.as_ref().unwrap().len()));
48 result.file_spans.push((f.start_pos.0, f.end_pos.0));
51 result.file_spans.sort();
56 pub fn filespans_for_span(&self, start: BytePos, end: BytePos) -> Vec<(u32, u32)> {
57 assert!(start.0 <= end.0);
59 if self.file_spans.len() == 0 {
63 // idx is the index into file_spans which indicates the current file, we
64 // with the file start denotes.
65 let mut idx = match self.file_spans.binary_search(&(start.0, ::std::u32::MAX)) {
71 let mut result = Vec::new();
72 let mut start = start.0;
74 let cur_file = &self.file_spans[idx];
77 if idx >= self.file_spans.len() || start >= end.0 {
79 result.push((start, end.0));
84 let end = ::std::cmp::min(cur_file.1 - 1, end.0);
86 result.push((start, end));
88 start = self.file_spans[idx].0;
92 pub fn push_str(&mut self, filename: &str, text: &str) {
93 let buf = self.file_map.get_mut(&*filename).unwrap();
97 pub fn push_str_span(&mut self, span: Span, text: &str) {
98 let file_name = self.codemap.span_to_filename(span);
99 self.push_str(&file_name, text)
102 pub fn cur_offset(&mut self, filename: &str) -> usize {
103 self.file_map[&*filename].cur_offset()
106 pub fn cur_offset_span(&mut self, span: Span) -> usize {
107 let filename = self.codemap.span_to_filename(span);
108 self.cur_offset(&filename)
111 // Return an iterator over the entire changed text.
112 pub fn text<'c>(&'c self) -> FileIterator<'c, 'a> {
115 keys: self.file_map.keys().collect(),
120 // Append a newline to the end of each file.
121 pub fn append_newlines(&mut self) {
122 for (_, s) in self.file_map.iter_mut() {
127 pub fn write_all_files(&self,
129 -> Result<(HashMap<String, String>), ::std::io::Error> {
130 let mut result = HashMap::new();
131 for filename in self.file_map.keys() {
132 let one_result = try!(self.write_file(filename, mode));
133 if let Some(r) = one_result {
134 result.insert(filename.clone(), r);
141 pub fn write_file(&self,
144 -> Result<Option<String>, ::std::io::Error> {
145 let text = &self.file_map[filename];
148 WriteMode::Overwrite => {
149 // Do a little dance to make writing safer - write to a temp file
150 // rename the original to a .bk, then rename the temp file to the
152 let tmp_name = filename.to_string() + ".tmp";
153 let bk_name = filename.to_string() + ".bk";
155 // Write text to temp file
156 let mut tmp_file = try!(File::create(&tmp_name));
157 try!(write!(tmp_file, "{}", text));
160 try!(::std::fs::rename(filename, bk_name));
161 try!(::std::fs::rename(tmp_name, filename));
163 WriteMode::NewFile(extn) => {
164 let filename = filename.to_string() + "." + extn;
165 let mut file = try!(File::create(&filename));
166 try!(write!(file, "{}", text));
168 WriteMode::Display => {
169 println!("{}:\n", filename);
170 println!("{}", text);
172 WriteMode::Return(_) => {
173 return Ok(Some(text.to_string()));
181 // Iterates over each file in the ChangSet. Yields the filename and the changed
182 // text for that file.
183 pub struct FileIterator<'c, 'a: 'c> {
184 change_set: &'c ChangeSet<'a>,
185 keys: Vec<&'c String>,
189 impl<'c, 'a> Iterator for FileIterator<'c, 'a> {
190 type Item = (&'c str, &'c StringBuffer);
192 fn next(&mut self) -> Option<(&'c str, &'c StringBuffer)> {
193 if self.cur_key >= self.keys.len() {
197 let key = self.keys[self.cur_key];
199 return Some((&key, &self.change_set.file_map[&*key]))
203 impl<'a> fmt::Display for ChangeSet<'a> {
204 // Prints the entire changed text.
205 fn fmt(&self, fmt: &mut fmt::Formatter) -> Result<(), fmt::Error> {
206 for (f, r) in self.text() {
207 try!(write!(fmt, "{}:\n", f));
208 try!(write!(fmt, "{}\n\n", r));