src/tools/rustfmt/src/test/configuration_snippet.rs

   1 use std::collections::{HashMap, HashSet};
   2 use std::fs;
   3 use std::io::{BufRead, BufReader, Write};
   4 use std::iter::Enumerate;
   5 use std::path::{Path, PathBuf};
   6
   7 use super::{print_mismatches, write_message, DIFF_CONTEXT_SIZE};
   8 use crate::config::{Config, EmitMode, Verbosity};
   9 use crate::rustfmt_diff::{make_diff, Mismatch};
  10 use crate::{Input, Session};
  11
  12 const CONFIGURATIONS_FILE_NAME: &str = "Configurations.md";
  13
  14 // This enum is used to represent one of three text features in Configurations.md: a block of code
  15 // with its starting line number, the name of a rustfmt configuration option, or the value of a
  16 // rustfmt configuration option.
  17 enum ConfigurationSection {
  18     CodeBlock((String, u32)), // (String: block of code, u32: line number of code block start)
  19     ConfigName(String),
  20     ConfigValue(String),
  21 }
  22
  23 impl ConfigurationSection {
  24     fn get_section<I: Iterator<Item = String>>(
  25         file: &mut Enumerate<I>,
  26     ) -> Option<ConfigurationSection> {
  27         lazy_static! {
  28             static ref CONFIG_NAME_REGEX: regex::Regex =
  29                 regex::Regex::new(r"^## `([^`]+)`").expect("failed creating configuration pattern");
  30             static ref CONFIG_VALUE_REGEX: regex::Regex =
  31                 regex::Regex::new(r#"^#### `"?([^`"]+)"?`"#)
  32                     .expect("failed creating configuration value pattern");
  33         }
  34
  35         loop {
  36             match file.next() {
  37                 Some((i, line)) => {
  38                     if line.starts_with("```rust") {
  39                         // Get the lines of the code block.
  40                         let lines: Vec<String> = file
  41                             .map(|(_i, l)| l)
  42                             .take_while(|l| !l.starts_with("```"))
  43                             .collect();
  44                         let block = format!("{}\n", lines.join("\n"));
  45
  46                         // +1 to translate to one-based indexing
  47                         // +1 to get to first line of code (line after "```")
  48                         let start_line = (i + 2) as u32;
  49
  50                         return Some(ConfigurationSection::CodeBlock((block, start_line)));
  51                     } else if let Some(c) = CONFIG_NAME_REGEX.captures(&line) {
  52                         return Some(ConfigurationSection::ConfigName(String::from(&c[1])));
  53                     } else if let Some(c) = CONFIG_VALUE_REGEX.captures(&line) {
  54                         return Some(ConfigurationSection::ConfigValue(String::from(&c[1])));
  55                     }
  56                 }
  57                 None => return None, // reached the end of the file
  58             }
  59         }
  60     }
  61 }
  62
  63 // This struct stores the information about code blocks in the configurations
  64 // file, formats the code blocks, and prints formatting errors.
  65 struct ConfigCodeBlock {
  66     config_name: Option<String>,
  67     config_value: Option<String>,
  68     code_block: Option<String>,
  69     code_block_start: Option<u32>,
  70 }
  71
  72 impl ConfigCodeBlock {
  73     fn new() -> ConfigCodeBlock {
  74         ConfigCodeBlock {
  75             config_name: None,
  76             config_value: None,
  77             code_block: None,
  78             code_block_start: None,
  79         }
  80     }
  81
  82     fn set_config_name(&mut self, name: Option<String>) {
  83         self.config_name = name;
  84         self.config_value = None;
  85     }
  86
  87     fn set_config_value(&mut self, value: Option<String>) {
  88         self.config_value = value;
  89     }
  90
  91     fn set_code_block(&mut self, code_block: String, code_block_start: u32) {
  92         self.code_block = Some(code_block);
  93         self.code_block_start = Some(code_block_start);
  94     }
  95
  96     fn get_block_config(&self) -> Config {
  97         let mut config = Config::default();
  98         config.set().verbose(Verbosity::Quiet);
  99         if self.config_name.is_some() && self.config_value.is_some() {
 100             config.override_value(
 101                 self.config_name.as_ref().unwrap(),
 102                 self.config_value.as_ref().unwrap(),
 103             );
 104         }
 105         config
 106     }
 107
 108     fn code_block_valid(&self) -> bool {
 109         // We never expect to not have a code block.
 110         assert!(self.code_block.is_some() && self.code_block_start.is_some());
 111
 112         // See if code block begins with #![rustfmt::skip].
 113         let fmt_skip = self.fmt_skip();
 114
 115         if self.config_name.is_none() && !fmt_skip {
 116             write_message(&format!(
 117                 "No configuration name for {}:{}",
 118                 CONFIGURATIONS_FILE_NAME,
 119                 self.code_block_start.unwrap()
 120             ));
 121             return false;
 122         }
 123         if self.config_value.is_none() && !fmt_skip {
 124             write_message(&format!(
 125                 "No configuration value for {}:{}",
 126                 CONFIGURATIONS_FILE_NAME,
 127                 self.code_block_start.unwrap()
 128             ));
 129             return false;
 130         }
 131         true
 132     }
 133
 134     /// True if the code block starts with #![rustfmt::skip]
 135     fn fmt_skip(&self) -> bool {
 136         self.code_block
 137             .as_ref()
 138             .unwrap()
 139             .lines()
 140             .nth(0)
 141             .unwrap_or("")
 142             == "#![rustfmt::skip]"
 143     }
 144
 145     fn has_parsing_errors<T: Write>(&self, session: &Session<'_, T>) -> bool {
 146         if session.has_parsing_errors() {
 147             write_message(&format!(
 148                 "\u{261d}\u{1f3fd} Cannot format {}:{}",
 149                 CONFIGURATIONS_FILE_NAME,
 150                 self.code_block_start.unwrap()
 151             ));
 152             return true;
 153         }
 154
 155         false
 156     }
 157
 158     fn print_diff(&self, compare: Vec<Mismatch>) {
 159         let mut mismatches = HashMap::new();
 160         mismatches.insert(PathBuf::from(CONFIGURATIONS_FILE_NAME), compare);
 161         print_mismatches(mismatches, |line_num| {
 162             format!(
 163                 "\nMismatch at {}:{}:",
 164                 CONFIGURATIONS_FILE_NAME,
 165                 line_num + self.code_block_start.unwrap() - 1
 166             )
 167         });
 168     }
 169
 170     fn formatted_has_diff(&self, text: &str) -> bool {
 171         let compare = make_diff(self.code_block.as_ref().unwrap(), text, DIFF_CONTEXT_SIZE);
 172         if !compare.is_empty() {
 173             self.print_diff(compare);
 174             return true;
 175         }
 176
 177         false
 178     }
 179
 180     // Return a bool indicating if formatting this code block is an idempotent
 181     // operation. This function also triggers printing any formatting failure
 182     // messages.
 183     fn formatted_is_idempotent(&self) -> bool {
 184         // Verify that we have all of the expected information.
 185         if !self.code_block_valid() {
 186             return false;
 187         }
 188
 189         let input = Input::Text(self.code_block.as_ref().unwrap().to_owned());
 190         let mut config = self.get_block_config();
 191         config.set().emit_mode(EmitMode::Stdout);
 192         let mut buf: Vec<u8> = vec![];
 193
 194         {
 195             let mut session = Session::new(config, Some(&mut buf));
 196             session.format(input).unwrap();
 197             if self.has_parsing_errors(&session) {
 198                 return false;
 199             }
 200         }
 201
 202         !self.formatted_has_diff(&String::from_utf8(buf).unwrap())
 203     }
 204
 205     // Extract a code block from the iterator. Behavior:
 206     // - Rust code blocks are identifed by lines beginning with "```rust".
 207     // - One explicit configuration setting is supported per code block.
 208     // - Rust code blocks with no configuration setting are illegal and cause an
 209     //   assertion failure, unless the snippet begins with #![rustfmt::skip].
 210     // - Configuration names in Configurations.md must be in the form of
 211     //   "## `NAME`".
 212     // - Configuration values in Configurations.md must be in the form of
 213     //   "#### `VALUE`".
 214     fn extract<I: Iterator<Item = String>>(
 215         file: &mut Enumerate<I>,
 216         prev: Option<&ConfigCodeBlock>,
 217         hash_set: &mut HashSet<String>,
 218     ) -> Option<ConfigCodeBlock> {
 219         let mut code_block = ConfigCodeBlock::new();
 220         code_block.config_name = prev.and_then(|cb| cb.config_name.clone());
 221
 222         loop {
 223             match ConfigurationSection::get_section(file) {
 224                 Some(ConfigurationSection::CodeBlock((block, start_line))) => {
 225                     code_block.set_code_block(block, start_line);
 226                     break;
 227                 }
 228                 Some(ConfigurationSection::ConfigName(name)) => {
 229                     assert!(
 230                         Config::is_valid_name(&name),
 231                         "an unknown configuration option was found: {}",
 232                         name
 233                     );
 234                     assert!(
 235                         hash_set.remove(&name),
 236                         "multiple configuration guides found for option {}",
 237                         name
 238                     );
 239                     code_block.set_config_name(Some(name));
 240                 }
 241                 Some(ConfigurationSection::ConfigValue(value)) => {
 242                     code_block.set_config_value(Some(value));
 243                 }
 244                 None => return None, // end of file was reached
 245             }
 246         }
 247
 248         Some(code_block)
 249     }
 250 }
 251
 252 #[test]
 253 fn configuration_snippet_tests() {
 254     super::init_log();
 255     let blocks = get_code_blocks();
 256     let failures = blocks
 257         .iter()
 258         .filter(|block| !block.fmt_skip())
 259         .map(ConfigCodeBlock::formatted_is_idempotent)
 260         .fold(0, |acc, r| acc + (!r as u32));
 261
 262     // Display results.
 263     println!("Ran {} configurations tests.", blocks.len());
 264     assert_eq!(failures, 0, "{} configurations tests failed", failures);
 265 }
 266
 267 // Read Configurations.md and build a `Vec` of `ConfigCodeBlock` structs with one
 268 // entry for each Rust code block found.
 269 fn get_code_blocks() -> Vec<ConfigCodeBlock> {
 270     let mut file_iter = BufReader::new(
 271         fs::File::open(Path::new(CONFIGURATIONS_FILE_NAME))
 272             .unwrap_or_else(|_| panic!("couldn't read file {}", CONFIGURATIONS_FILE_NAME)),
 273     )
 274     .lines()
 275     .map(Result::unwrap)
 276     .enumerate();
 277     let mut code_blocks: Vec<ConfigCodeBlock> = Vec::new();
 278     let mut hash_set = Config::hash_set();
 279
 280     while let Some(cb) = ConfigCodeBlock::extract(&mut file_iter, code_blocks.last(), &mut hash_set)
 281     {
 282         code_blocks.push(cb);
 283     }
 284
 285     for name in hash_set {
 286         if !Config::is_hidden_option(&name) {
 287             panic!("{} does not have a configuration guide", name);
 288         }
 289     }
 290
 291     code_blocks
 292 }
 293
 294 #[test]
 295 fn check_unstable_option_tracking_issue_numbers() {
 296     // Ensure that tracking issue links point to the correct issue number
 297     let tracking_issue =
 298         regex::Regex::new(r"\(tracking issue: \[#(?P<number>\d+)\]\((?P<link>\S+)\)\)")
 299             .expect("failed creating configuration pattern");
 300
 301     let lines = BufReader::new(
 302         fs::File::open(Path::new(CONFIGURATIONS_FILE_NAME))
 303             .unwrap_or_else(|_| panic!("couldn't read file {}", CONFIGURATIONS_FILE_NAME)),
 304     )
 305     .lines()
 306     .map(Result::unwrap)
 307     .enumerate();
 308
 309     for (idx, line) in lines {
 310         if let Some(capture) = tracking_issue.captures(&line) {
 311             let number = capture.name("number").unwrap().as_str();
 312             let link = capture.name("link").unwrap().as_str();
 313             assert!(
 314                 link.ends_with(number),
 315                 "{} on line {} does not point to issue #{}",
 316                 link,
 317                 idx + 1,
 318                 number,
 319             );
 320         }
 321     }
 322 }