1 // Inspired by Clang's clang-format-diff:
2 //
3 // https://github.com/llvm-mirror/clang/blob/master/tools/clang-format/clang-format-diff.py
4
5 #![deny(warnings)]
6
7 #[macro_use]
8 extern crate log;
9
10 use serde::{Deserialize, Serialize};
11 use serde_json as json;
12 use thiserror::Error;
13
14 use std::collections::HashSet;
15 use std::env;
16 use std::ffi::OsStr;
17 use std::io::{self, BufRead};
18 use std::process;
19
20 use regex::Regex;
21
22 use structopt::clap::AppSettings;
23 use structopt::StructOpt;
24
25 /// The default pattern of files to format.
26 ///
27 /// We only want to format rust files by default.
28 const DEFAULT_PATTERN: &str = r".*\.rs";
29
30 #[derive(Error, Debug)]
31 enum FormatDiffError {
32 #[error("{0}")]
33 IncorrectOptions(#[from] getopts::Fail),
34 #[error("{0}")]
35 IncorrectFilter(#[from] regex::Error),
36 #[error("{0}")]
37 IoError(#[from] io::Error),
38 }
39
40 #[derive(StructOpt, Debug)]
41 #[structopt(
42 name = "rustfmt-format-diff",
43 setting = AppSettings::DisableVersion,
44 setting = AppSettings::NextLineHelp
45 )]
46 pub struct Opts {
47 /// Skip the smallest prefix containing NUMBER slashes
48 #[structopt(
49 short = "p",
50 long = "skip-prefix",
51 value_name = "NUMBER",
52 default_value = "0"
53 )]
54 skip_prefix: u32,
55
56 /// Custom pattern selecting file paths to reformat
57 #[structopt(
58 short = "f",
59 long = "filter",
60 value_name = "PATTERN",
61 default_value = DEFAULT_PATTERN
62 )]
63 filter: String,
64 }
65
main()66 fn main() {
67 env_logger::Builder::from_env("RUSTFMT_LOG").init();
68 let opts = Opts::from_args();
69 if let Err(e) = run(opts) {
70 println!("{}", e);
71 Opts::clap().print_help().expect("cannot write to stdout");
72 process::exit(1);
73 }
74 }
75
76 #[derive(Debug, Eq, PartialEq, Serialize, Deserialize)]
77 struct Range {
78 file: String,
79 range: [u32; 2],
80 }
81
run(opts: Opts) -> Result<(), FormatDiffError>82 fn run(opts: Opts) -> Result<(), FormatDiffError> {
83 let (files, ranges) = scan_diff(io::stdin(), opts.skip_prefix, &opts.filter)?;
84 run_rustfmt(&files, &ranges)
85 }
86
run_rustfmt(files: &HashSet<String>, ranges: &[Range]) -> Result<(), FormatDiffError>87 fn run_rustfmt(files: &HashSet<String>, ranges: &[Range]) -> Result<(), FormatDiffError> {
88 if files.is_empty() || ranges.is_empty() {
89 debug!("No files to format found");
90 return Ok(());
91 }
92
93 let ranges_as_json = json::to_string(ranges).unwrap();
94
95 debug!("Files: {:?}", files);
96 debug!("Ranges: {:?}", ranges);
97
98 let rustfmt_var = env::var_os("RUSTFMT");
99 let rustfmt = match &rustfmt_var {
100 Some(rustfmt) => rustfmt,
101 None => OsStr::new("rustfmt"),
102 };
103 let exit_status = process::Command::new(rustfmt)
104 .args(files)
105 .arg("--file-lines")
106 .arg(ranges_as_json)
107 .status()?;
108
109 if !exit_status.success() {
110 return Err(FormatDiffError::IoError(io::Error::new(
111 io::ErrorKind::Other,
112 format!("rustfmt failed with {}", exit_status),
113 )));
114 }
115 Ok(())
116 }
117
118 /// Scans a diff from `from`, and returns the set of files found, and the ranges
119 /// in those files.
scan_diff<R>( from: R, skip_prefix: u32, file_filter: &str, ) -> Result<(HashSet<String>, Vec<Range>), FormatDiffError> where R: io::Read,120 fn scan_diff<R>(
121 from: R,
122 skip_prefix: u32,
123 file_filter: &str,
124 ) -> Result<(HashSet<String>, Vec<Range>), FormatDiffError>
125 where
126 R: io::Read,
127 {
128 let diff_pattern = format!(r"^\+\+\+\s(?:.*?/){{{}}}(\S*)", skip_prefix);
129 let diff_pattern = Regex::new(&diff_pattern).unwrap();
130
131 let lines_pattern = Regex::new(r"^@@.*\+(\d+)(,(\d+))?").unwrap();
132
133 let file_filter = Regex::new(&format!("^{}$", file_filter))?;
134
135 let mut current_file = None;
136
137 let mut files = HashSet::new();
138 let mut ranges = vec![];
139 for line in io::BufReader::new(from).lines() {
140 let line = line.unwrap();
141
142 if let Some(captures) = diff_pattern.captures(&line) {
143 current_file = Some(captures.get(1).unwrap().as_str().to_owned());
144 }
145
146 let file = match current_file {
147 Some(ref f) => &**f,
148 None => continue,
149 };
150
151 // FIXME(emilio): We could avoid this most of the time if needed, but
152 // it's not clear it's worth it.
153 if !file_filter.is_match(file) {
154 continue;
155 }
156
157 let lines_captures = match lines_pattern.captures(&line) {
158 Some(captures) => captures,
159 None => continue,
160 };
161
162 let start_line = lines_captures
163 .get(1)
164 .unwrap()
165 .as_str()
166 .parse::<u32>()
167 .unwrap();
168 let line_count = match lines_captures.get(3) {
169 Some(line_count) => line_count.as_str().parse::<u32>().unwrap(),
170 None => 1,
171 };
172
173 if line_count == 0 {
174 continue;
175 }
176
177 let end_line = start_line + line_count - 1;
178 files.insert(file.to_owned());
179 ranges.push(Range {
180 file: file.to_owned(),
181 range: [start_line, end_line],
182 });
183 }
184
185 Ok((files, ranges))
186 }
187
188 #[test]
scan_simple_git_diff()189 fn scan_simple_git_diff() {
190 const DIFF: &str = include_str!("test/bindgen.diff");
191 let (files, ranges) = scan_diff(DIFF.as_bytes(), 1, r".*\.rs").expect("scan_diff failed?");
192
193 assert!(
194 files.contains("src/ir/traversal.rs"),
195 "Should've matched the filter"
196 );
197
198 assert!(
199 !files.contains("tests/headers/anon_enum.hpp"),
200 "Shouldn't have matched the filter"
201 );
202
203 assert_eq!(
204 &ranges,
205 &[
206 Range {
207 file: "src/ir/item.rs".to_owned(),
208 range: [148, 158],
209 },
210 Range {
211 file: "src/ir/item.rs".to_owned(),
212 range: [160, 170],
213 },
214 Range {
215 file: "src/ir/traversal.rs".to_owned(),
216 range: [9, 16],
217 },
218 Range {
219 file: "src/ir/traversal.rs".to_owned(),
220 range: [35, 43],
221 },
222 ]
223 );
224 }
225
226 #[cfg(test)]
227 mod cmd_line_tests {
228 use super::*;
229
230 #[test]
default_options()231 fn default_options() {
232 let empty: Vec<String> = vec![];
233 let o = Opts::from_iter(&empty);
234 assert_eq!(DEFAULT_PATTERN, o.filter);
235 assert_eq!(0, o.skip_prefix);
236 }
237
238 #[test]
good_options()239 fn good_options() {
240 let o = Opts::from_iter(&["test", "-p", "10", "-f", r".*\.hs"]);
241 assert_eq!(r".*\.hs", o.filter);
242 assert_eq!(10, o.skip_prefix);
243 }
244
245 #[test]
unexpected_option()246 fn unexpected_option() {
247 assert!(
248 Opts::clap()
249 .get_matches_from_safe(&["test", "unexpected"])
250 .is_err()
251 );
252 }
253
254 #[test]
unexpected_flag()255 fn unexpected_flag() {
256 assert!(
257 Opts::clap()
258 .get_matches_from_safe(&["test", "--flag"])
259 .is_err()
260 );
261 }
262
263 #[test]
overridden_option()264 fn overridden_option() {
265 assert!(
266 Opts::clap()
267 .get_matches_from_safe(&["test", "-p", "10", "-p", "20"])
268 .is_err()
269 );
270 }
271
272 #[test]
negative_filter()273 fn negative_filter() {
274 assert!(
275 Opts::clap()
276 .get_matches_from_safe(&["test", "-p", "-1"])
277 .is_err()
278 );
279 }
280 }
281