src/tools/clippy/clippy_dev/src/lib.rs - third_party/rust - Git at Google

 #![cfg_attr(feature = "deny-warnings", deny(warnings))]

 use itertools::Itertools;
 use lazy_static::lazy_static;
 use regex::Regex;
 use std::collections::HashMap;
 use std::ffi::OsStr;
 use std::fs;
 use std::path::{Path, PathBuf};
 use walkdir::WalkDir;

 pub mod fmt;
 pub mod new_lint;
 pub mod ra_setup;
 pub mod stderr_length_check;
 pub mod update_lints;

 lazy_static! {
     static ref DEC_CLIPPY_LINT_RE: Regex = Regex::new(
         r#"(?x)
         declare_clippy_lint!\s*[\{(]
         (?:\s+///.*)*
         \s+pub\s+(?P<name>[A-Z_][A-Z_0-9]*)\s*,\s*
         (?P<cat>[a-z_]+)\s*,\s*
         "(?P<desc>(?:[^"\\]+|\\(?s).(?-s))*)"\s*[})]
     "#
     )
     .unwrap();
     static ref DEC_DEPRECATED_LINT_RE: Regex = Regex::new(
         r#"(?x)
         declare_deprecated_lint!\s*[{(]\s*
         (?:\s+///.*)*
         \s+pub\s+(?P<name>[A-Z_][A-Z_0-9]*)\s*,\s*
         "(?P<desc>(?:[^"\\]+|\\(?s).(?-s))*)"\s*[})]
     "#
     )
     .unwrap();
     static ref NL_ESCAPE_RE: Regex = Regex::new(r#"\\\n\s*"#).unwrap();
 }

 pub static DOCS_LINK: &str = "https://rust-lang.github.io/rust-clippy/master/index.html";

 /// Lint data parsed from the Clippy source code.
 #[derive(Clone, PartialEq, Debug)]
 pub struct Lint {
     pub name: String,
     pub group: String,
     pub desc: String,
     pub deprecation: Option<String>,
     pub module: String,
 }

 impl Lint {
     #[must_use]
     pub fn new(name: &str, group: &str, desc: &str, deprecation: Option<&str>, module: &str) -> Self {
         Self {
             name: name.to_lowercase(),
             group: group.to_string(),
             desc: NL_ESCAPE_RE.replace(&desc.replace("\\\"", "\""), "").to_string(),
             deprecation: deprecation.map(ToString::to_string),
             module: module.to_string(),
         }
     }

     /// Returns all non-deprecated lints and non-internal lints
     #[must_use]
     pub fn usable_lints(lints: &[Self]) -> Vec<Self> {
         lints
             .iter()
             .filter(|l| l.deprecation.is_none() && !l.group.starts_with("internal"))
             .cloned()
             .collect()
     }

     /// Returns all internal lints (not `internal_warn` lints)
     #[must_use]
     pub fn internal_lints(lints: &[Self]) -> Vec<Self> {
         lints.iter().filter(|l| l.group == "internal").cloned().collect()
     }

     /// Returns all deprecated lints
     #[must_use]
     pub fn deprecated_lints(lints: &[Self]) -> Vec<Self> {
         lints.iter().filter(|l| l.deprecation.is_some()).cloned().collect()
     }

     /// Returns the lints in a `HashMap`, grouped by the different lint groups
     #[must_use]
     pub fn by_lint_group(lints: impl Iterator<Item = Self>) -> HashMap<String, Vec<Self>> {
         lints.map(|lint| (lint.group.to_string(), lint)).into_group_map()
     }
 }

 /// Generates the Vec items for `register_lint_group` calls in `clippy_lints/src/lib.rs`.
 #[must_use]
 pub fn gen_lint_group_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     lints
         .map(|l| format!("        LintId::of(&{}::{}),", l.module, l.name.to_uppercase()))
         .sorted()
         .collect::<Vec<String>>()
 }

 /// Generates the `pub mod module_name` list in `clippy_lints/src/lib.rs`.
 #[must_use]
 pub fn gen_modules_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     lints
         .map(|l| &l.module)
         .unique()
         .map(|module| format!("mod {};", module))
         .sorted()
         .collect::<Vec<String>>()
 }

 /// Generates the list of lint links at the bottom of the README
 #[must_use]
 pub fn gen_changelog_lint_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     lints
         .sorted_by_key(|l| &l.name)
         .map(|l| format!("[`{}`]: {}#{}", l.name, DOCS_LINK, l.name))
         .collect()
 }

 /// Generates the `register_removed` code in `./clippy_lints/src/lib.rs`.
 #[must_use]
 pub fn gen_deprecated<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     lints
         .flat_map(|l| {
             l.deprecation
                 .clone()
                 .map(|depr_text| {
                     vec![
                         "    store.register_removed(".to_string(),
                         format!("        \"clippy::{}\",", l.name),
                         format!("        \"{}\",", depr_text),
                         "    );".to_string(),
                     ]
                 })
                 .expect("only deprecated lints should be passed")
         })
         .collect::<Vec<String>>()
 }

 #[must_use]
 pub fn gen_register_lint_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
     let pre = "    store.register_lints(&[".to_string();
     let post = "    ]);".to_string();
     let mut inner = lints
         .map(|l| format!("        &{}::{},", l.module, l.name.to_uppercase()))
         .sorted()
         .collect::<Vec<String>>();
     inner.insert(0, pre);
     inner.push(post);
     inner
 }

 /// Gathers all files in `src/clippy_lints` and gathers all lints inside
 pub fn gather_all() -> impl Iterator<Item = Lint> {
     lint_files().flat_map(|f| gather_from_file(&f))
 }

 fn gather_from_file(dir_entry: &walkdir::DirEntry) -> impl Iterator<Item = Lint> {
     let content = fs::read_to_string(dir_entry.path()).unwrap();
     let path = dir_entry.path();
     let filename = path.file_stem().unwrap();
     let path_buf = path.with_file_name(filename);
     let mut rel_path = path_buf
         .strip_prefix(clippy_project_root().join("clippy_lints/src"))
         .expect("only files in `clippy_lints/src` should be looked at");
     // If the lints are stored in mod.rs, we get the module name from
     // the containing directory:
     if filename == "mod" {
         rel_path = rel_path.parent().unwrap();
     }

     let module = rel_path
         .components()
         .map(|c| c.as_os_str().to_str().unwrap())
         .collect::<Vec<_>>()
         .join("::");

     parse_contents(&content, &module)
 }

 fn parse_contents(content: &str, module: &str) -> impl Iterator<Item = Lint> {
     let lints = DEC_CLIPPY_LINT_RE
         .captures_iter(content)
         .map(|m| Lint::new(&m["name"], &m["cat"], &m["desc"], None, module));
     let deprecated = DEC_DEPRECATED_LINT_RE
         .captures_iter(content)
         .map(|m| Lint::new(&m["name"], "Deprecated", &m["desc"], Some(&m["desc"]), module));
     // Removing the `.collect::<Vec<Lint>>().into_iter()` causes some lifetime issues due to the map
     lints.chain(deprecated).collect::<Vec<Lint>>().into_iter()
 }

 /// Collects all .rs files in the `clippy_lints/src` directory
 fn lint_files() -> impl Iterator<Item = walkdir::DirEntry> {
     // We use `WalkDir` instead of `fs::read_dir` here in order to recurse into subdirectories.
     // Otherwise we would not collect all the lints, for example in `clippy_lints/src/methods/`.
     let path = clippy_project_root().join("clippy_lints/src");
     WalkDir::new(path)
         .into_iter()
         .filter_map(Result::ok)
         .filter(|f| f.path().extension() == Some(OsStr::new("rs")))
 }

 /// Whether a file has had its text changed or not
 #[derive(PartialEq, Debug)]
 pub struct FileChange {
     pub changed: bool,
     pub new_lines: String,
 }

 /// Replaces a region in a file delimited by two lines matching regexes.
 ///
 /// `path` is the relative path to the file on which you want to perform the replacement.
 ///
 /// See `replace_region_in_text` for documentation of the other options.
 pub fn replace_region_in_file<F>(
     path: &Path,
     start: &str,
     end: &str,
     replace_start: bool,
     write_back: bool,
     replacements: F,
 ) -> FileChange
 where
     F: FnOnce() -> Vec<String>,
 {
     let contents = fs::read_to_string(path).unwrap_or_else(|e| panic!("Cannot read from {}: {}", path.display(), e));
     let file_change = replace_region_in_text(&contents, start, end, replace_start, replacements);

     if write_back {
         if let Err(e) = fs::write(path, file_change.new_lines.as_bytes()) {
             panic!("Cannot write to {}: {}", path.display(), e);
         }
     }
     file_change
 }

 /// Replaces a region in a text delimited by two lines matching regexes.
 ///
 /// * `text` is the input text on which you want to perform the replacement
 /// * `start` is a `&str` that describes the delimiter line before the region you want to replace.
 ///   As the `&str` will be converted to a `Regex`, this can contain regex syntax, too.
 /// * `end` is a `&str` that describes the delimiter line until where the replacement should happen.
 ///   As the `&str` will be converted to a `Regex`, this can contain regex syntax, too.
 /// * If `replace_start` is true, the `start` delimiter line is replaced as well. The `end`
 ///   delimiter line is never replaced.
 /// * `replacements` is a closure that has to return a `Vec<String>` which contains the new text.
 ///
 /// If you want to perform the replacement on files instead of already parsed text,
 /// use `replace_region_in_file`.
 ///
 /// # Example
 ///
 /// ```
 /// let the_text = "replace_start\nsome text\nthat will be replaced\nreplace_end";
 /// let result =
 ///     clippy_dev::replace_region_in_text(the_text, "replace_start", "replace_end", false, || {
 ///         vec!["a different".to_string(), "text".to_string()]
 ///     })
 ///     .new_lines;
 /// assert_eq!("replace_start\na different\ntext\nreplace_end", result);
 /// ```
 pub fn replace_region_in_text<F>(text: &str, start: &str, end: &str, replace_start: bool, replacements: F) -> FileChange
 where
     F: FnOnce() -> Vec<String>,
 {
     let replace_it = replacements();
     let mut in_old_region = false;
     let mut found = false;
     let mut new_lines = vec![];
     let start = Regex::new(start).unwrap();
     let end = Regex::new(end).unwrap();

     for line in text.lines() {
         if in_old_region {
             if end.is_match(line) {
                 in_old_region = false;
                 new_lines.extend(replace_it.clone());
                 new_lines.push(line.to_string());
             }
         } else if start.is_match(line) {
             if !replace_start {
                 new_lines.push(line.to_string());
             }
             in_old_region = true;
             found = true;
         } else {
             new_lines.push(line.to_string());
         }
     }

     if !found {
         // This happens if the provided regex in `clippy_dev/src/main.rs` does not match in the
         // given text or file. Most likely this is an error on the programmer's side and the Regex
         // is incorrect.
         eprintln!("error: regex \n{:?}\ndoesn't match. You may have to update it.", start);
         std::process::exit(1);
     }

     let mut new_lines = new_lines.join("\n");
     if text.ends_with('\n') {
         new_lines.push('\n');
     }
     let changed = new_lines != text;
     FileChange { changed, new_lines }
 }

 /// Returns the path to the Clippy project directory
 #[must_use]
 pub fn clippy_project_root() -> PathBuf {
     let current_dir = std::env::current_dir().unwrap();
     for path in current_dir.ancestors() {
         let result = std::fs::read_to_string(path.join("Cargo.toml"));
         if let Err(err) = &result {
             if err.kind() == std::io::ErrorKind::NotFound {
                 continue;
             }
         }

         let content = result.unwrap();
         if content.contains("[package]\nname = \"clippy\"") {
             return path.to_path_buf();
         }
     }
     panic!("error: Can't determine root of project. Please run inside a Clippy working dir.");
 }

 #[test]
 fn test_parse_contents() {
     let result: Vec<Lint> = parse_contents(
         r#"
 declare_clippy_lint! {
     pub PTR_ARG,
     style,
     "really long \
      text"
 }

 declare_clippy_lint!{
     pub DOC_MARKDOWN,
     pedantic,
     "single line"
 }

 /// some doc comment
 declare_deprecated_lint! {
     pub SHOULD_ASSERT_EQ,
     "`assert!()` will be more flexible with RFC 2011"
 }
     "#,
         "module_name",
     )
     .collect();

     let expected = vec![
         Lint::new("ptr_arg", "style", "really long text", None, "module_name"),
         Lint::new("doc_markdown", "pedantic", "single line", None, "module_name"),
         Lint::new(
             "should_assert_eq",
             "Deprecated",
             "`assert!()` will be more flexible with RFC 2011",
             Some("`assert!()` will be more flexible with RFC 2011"),
             "module_name",
         ),
     ];
     assert_eq!(expected, result);
 }

 #[test]
 fn test_replace_region() {
     let text = "\nabc\n123\n789\ndef\nghi";
     let expected = FileChange {
         changed: true,
         new_lines: "\nabc\nhello world\ndef\nghi".to_string(),
     };
     let result = replace_region_in_text(text, r#"^\s*abc$"#, r#"^\s*def"#, false, || {
         vec!["hello world".to_string()]
     });
     assert_eq!(expected, result);
 }

 #[test]
 fn test_replace_region_with_start() {
     let text = "\nabc\n123\n789\ndef\nghi";
     let expected = FileChange {
         changed: true,
         new_lines: "\nhello world\ndef\nghi".to_string(),
     };
     let result = replace_region_in_text(text, r#"^\s*abc$"#, r#"^\s*def"#, true, || {
         vec!["hello world".to_string()]
     });
     assert_eq!(expected, result);
 }

 #[test]
 fn test_replace_region_no_changes() {
     let text = "123\n456\n789";
     let expected = FileChange {
         changed: false,
         new_lines: "123\n456\n789".to_string(),
     };
     let result = replace_region_in_text(text, r#"^\s*123$"#, r#"^\s*456"#, false, Vec::new);
     assert_eq!(expected, result);
 }

 #[test]
 fn test_usable_lints() {
     let lints = vec![
         Lint::new("should_assert_eq", "Deprecated", "abc", Some("Reason"), "module_name"),
         Lint::new("should_assert_eq2", "Not Deprecated", "abc", None, "module_name"),
         Lint::new("should_assert_eq2", "internal", "abc", None, "module_name"),
         Lint::new("should_assert_eq2", "internal_style", "abc", None, "module_name"),
     ];
     let expected = vec![Lint::new(
         "should_assert_eq2",
         "Not Deprecated",
         "abc",
         None,
         "module_name",
     )];
     assert_eq!(expected, Lint::usable_lints(&lints));
 }

 #[test]
 fn test_by_lint_group() {
     let lints = vec![
         Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
         Lint::new("should_assert_eq2", "group2", "abc", None, "module_name"),
         Lint::new("incorrect_match", "group1", "abc", None, "module_name"),
     ];
     let mut expected: HashMap<String, Vec<Lint>> = HashMap::new();
     expected.insert(
         "group1".to_string(),
         vec![
             Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
             Lint::new("incorrect_match", "group1", "abc", None, "module_name"),
         ],
     );
     expected.insert(
         "group2".to_string(),
         vec![Lint::new("should_assert_eq2", "group2", "abc", None, "module_name")],
     );
     assert_eq!(expected, Lint::by_lint_group(lints.into_iter()));
 }

 #[test]
 fn test_gen_changelog_lint_list() {
     let lints = vec![
         Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
         Lint::new("should_assert_eq2", "group2", "abc", None, "module_name"),
     ];
     let expected = vec![
         format!("[`should_assert_eq`]: {}#should_assert_eq", DOCS_LINK.to_string()),
         format!("[`should_assert_eq2`]: {}#should_assert_eq2", DOCS_LINK.to_string()),
     ];
     assert_eq!(expected, gen_changelog_lint_list(lints.iter()));
 }

 #[test]
 fn test_gen_deprecated() {
     let lints = vec![
         Lint::new(
             "should_assert_eq",
             "group1",
             "abc",
             Some("has been superseded by should_assert_eq2"),
             "module_name",
         ),
         Lint::new(
             "another_deprecated",
             "group2",
             "abc",
             Some("will be removed"),
             "module_name",
         ),
     ];
     let expected: Vec<String> = vec![
         "    store.register_removed(",
         "        \"clippy::should_assert_eq\",",
         "        \"has been superseded by should_assert_eq2\",",
         "    );",
         "    store.register_removed(",
         "        \"clippy::another_deprecated\",",
         "        \"will be removed\",",
         "    );",
     ]
     .into_iter()
     .map(String::from)
     .collect();
     assert_eq!(expected, gen_deprecated(lints.iter()));
 }

 #[test]
 #[should_panic]
 fn test_gen_deprecated_fail() {
     let lints = vec![Lint::new("should_assert_eq2", "group2", "abc", None, "module_name")];
     let _ = gen_deprecated(lints.iter());
 }

 #[test]
 fn test_gen_modules_list() {
     let lints = vec![
         Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
         Lint::new("incorrect_stuff", "group3", "abc", None, "another_module"),
     ];
     let expected = vec!["mod another_module;".to_string(), "mod module_name;".to_string()];
     assert_eq!(expected, gen_modules_list(lints.iter()));
 }

 #[test]
 fn test_gen_lint_group_list() {
     let lints = vec![
         Lint::new("abc", "group1", "abc", None, "module_name"),
         Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
         Lint::new("internal", "internal_style", "abc", None, "module_name"),
     ];
     let expected = vec![
         "        LintId::of(&module_name::ABC),".to_string(),
         "        LintId::of(&module_name::INTERNAL),".to_string(),
         "        LintId::of(&module_name::SHOULD_ASSERT_EQ),".to_string(),
     ];
     assert_eq!(expected, gen_lint_group_list(lints.iter()));
 }
	#![cfg_attr(feature = "deny-warnings", deny(warnings))]

	use itertools::Itertools;
	use lazy_static::lazy_static;
	use regex::Regex;
	use std::collections::HashMap;
	use std::ffi::OsStr;
	use std::fs;
	use std::path::{Path, PathBuf};
	use walkdir::WalkDir;

	pub mod fmt;
	pub mod new_lint;
	pub mod ra_setup;
	pub mod stderr_length_check;
	pub mod update_lints;

	lazy_static! {
	static ref DEC_CLIPPY_LINT_RE: Regex = Regex::new(
	r#"(?x)
	declare_clippy_lint!\s*[\{(]
	(?:\s+///.)
	\s+pub\s+(?P<name>[A-Z_][A-Z_0-9])\s,\s*
	(?P<cat>[a-z_]+)\s,\s
	"(?P<desc>(?:[^"\\]+\|\\(?s).(?-s)))"\s[})]
	"#
	)
	.unwrap();
	static ref DEC_DEPRECATED_LINT_RE: Regex = Regex::new(
	r#"(?x)
	declare_deprecated_lint!\s[{(]\s
	(?:\s+///.)
	\s+pub\s+(?P<name>[A-Z_][A-Z_0-9])\s,\s*
	"(?P<desc>(?:[^"\\]+\|\\(?s).(?-s)))"\s[})]
	"#
	)
	.unwrap();
	static ref NL_ESCAPE_RE: Regex = Regex::new(r#"\\\n\s*"#).unwrap();
	}

	pub static DOCS_LINK: &str = "https://rust-lang.github.io/rust-clippy/master/index.html";

	/// Lint data parsed from the Clippy source code.
	#[derive(Clone, PartialEq, Debug)]
	pub struct Lint {
	pub name: String,
	pub group: String,
	pub desc: String,
	pub deprecation: Option<String>,
	pub module: String,
	}

	impl Lint {
	#[must_use]
	pub fn new(name: &str, group: &str, desc: &str, deprecation: Option<&str>, module: &str) -> Self {
	Self {
	name: name.to_lowercase(),
	group: group.to_string(),
	desc: NL_ESCAPE_RE.replace(&desc.replace("\\\"", "\""), "").to_string(),
	deprecation: deprecation.map(ToString::to_string),
	module: module.to_string(),
	}
	}

	/// Returns all non-deprecated lints and non-internal lints
	#[must_use]
	pub fn usable_lints(lints: &[Self]) -> Vec<Self> {
	lints
	.iter()
	.filter(\|l\| l.deprecation.is_none() && !l.group.starts_with("internal"))
	.cloned()
	.collect()
	}

	/// Returns all internal lints (not `internal_warn` lints)
	#[must_use]
	pub fn internal_lints(lints: &[Self]) -> Vec<Self> {
	lints.iter().filter(\|l\| l.group == "internal").cloned().collect()
	}

	/// Returns all deprecated lints
	#[must_use]
	pub fn deprecated_lints(lints: &[Self]) -> Vec<Self> {
	lints.iter().filter(\|l\| l.deprecation.is_some()).cloned().collect()
	}

	/// Returns the lints in a `HashMap`, grouped by the different lint groups
	#[must_use]
	pub fn by_lint_group(lints: impl Iterator<Item = Self>) -> HashMap<String, Vec<Self>> {
	lints.map(\|lint\| (lint.group.to_string(), lint)).into_group_map()
	}
	}

	/// Generates the Vec items for `register_lint_group` calls in `clippy_lints/src/lib.rs`.
	#[must_use]
	pub fn gen_lint_group_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
	lints
	.map(\|l\| format!(" LintId::of(&{}::{}),", l.module, l.name.to_uppercase()))
	.sorted()
	.collect::<Vec<String>>()
	}

	/// Generates the `pub mod module_name` list in `clippy_lints/src/lib.rs`.
	#[must_use]
	pub fn gen_modules_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
	lints
	.map(\|l\| &l.module)
	.unique()
	.map(\|module\| format!("mod {};", module))
	.sorted()
	.collect::<Vec<String>>()
	}

	/// Generates the list of lint links at the bottom of the README
	#[must_use]
	pub fn gen_changelog_lint_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
	lints
	.sorted_by_key(\|l\| &l.name)
	.map(\|l\| format!("[`{}`]: {}#{}", l.name, DOCS_LINK, l.name))
	.collect()
	}

	/// Generates the `register_removed` code in `./clippy_lints/src/lib.rs`.
	#[must_use]
	pub fn gen_deprecated<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
	lints
	.flat_map(\|l\| {
	l.deprecation
	.clone()
	.map(\|depr_text\| {
	vec![
	" store.register_removed(".to_string(),
	format!(" \"clippy::{}\",", l.name),
	format!(" \"{}\",", depr_text),
	" );".to_string(),
	]
	})
	.expect("only deprecated lints should be passed")
	})
	.collect::<Vec<String>>()
	}

	#[must_use]
	pub fn gen_register_lint_list<'a>(lints: impl Iterator<Item = &'a Lint>) -> Vec<String> {
	let pre = " store.register_lints(&[".to_string();
	let post = " ]);".to_string();
	let mut inner = lints
	.map(\|l\| format!(" &{}::{},", l.module, l.name.to_uppercase()))
	.sorted()
	.collect::<Vec<String>>();
	inner.insert(0, pre);
	inner.push(post);
	inner
	}

	/// Gathers all files in `src/clippy_lints` and gathers all lints inside
	pub fn gather_all() -> impl Iterator<Item = Lint> {
	lint_files().flat_map(\|f\| gather_from_file(&f))
	}

	fn gather_from_file(dir_entry: &walkdir::DirEntry) -> impl Iterator<Item = Lint> {
	let content = fs::read_to_string(dir_entry.path()).unwrap();
	let path = dir_entry.path();
	let filename = path.file_stem().unwrap();
	let path_buf = path.with_file_name(filename);
	let mut rel_path = path_buf
	.strip_prefix(clippy_project_root().join("clippy_lints/src"))
	.expect("only files in `clippy_lints/src` should be looked at");
	// If the lints are stored in mod.rs, we get the module name from
	// the containing directory:
	if filename == "mod" {
	rel_path = rel_path.parent().unwrap();
	}

	let module = rel_path
	.components()
	.map(\|c\| c.as_os_str().to_str().unwrap())
	.collect::<Vec<_>>()
	.join("::");

	parse_contents(&content, &module)
	}

	fn parse_contents(content: &str, module: &str) -> impl Iterator<Item = Lint> {
	let lints = DEC_CLIPPY_LINT_RE
	.captures_iter(content)
	.map(\|m\| Lint::new(&m["name"], &m["cat"], &m["desc"], None, module));
	let deprecated = DEC_DEPRECATED_LINT_RE
	.captures_iter(content)
	.map(\|m\| Lint::new(&m["name"], "Deprecated", &m["desc"], Some(&m["desc"]), module));
	// Removing the `.collect::<Vec<Lint>>().into_iter()` causes some lifetime issues due to the map
	lints.chain(deprecated).collect::<Vec<Lint>>().into_iter()
	}

	/// Collects all .rs files in the `clippy_lints/src` directory
	fn lint_files() -> impl Iterator<Item = walkdir::DirEntry> {
	// We use `WalkDir` instead of `fs::read_dir` here in order to recurse into subdirectories.
	// Otherwise we would not collect all the lints, for example in `clippy_lints/src/methods/`.
	let path = clippy_project_root().join("clippy_lints/src");
	WalkDir::new(path)
	.into_iter()
	.filter_map(Result::ok)
	.filter(\|f\| f.path().extension() == Some(OsStr::new("rs")))
	}

	/// Whether a file has had its text changed or not
	#[derive(PartialEq, Debug)]
	pub struct FileChange {
	pub changed: bool,
	pub new_lines: String,
	}

	/// Replaces a region in a file delimited by two lines matching regexes.
	///
	/// `path` is the relative path to the file on which you want to perform the replacement.
	///
	/// See `replace_region_in_text` for documentation of the other options.
	pub fn replace_region_in_file<F>(
	path: &Path,
	start: &str,
	end: &str,
	replace_start: bool,
	write_back: bool,
	replacements: F,
	) -> FileChange
	where
	F: FnOnce() -> Vec<String>,
	{
	let contents = fs::read_to_string(path).unwrap_or_else(\|e\| panic!("Cannot read from {}: {}", path.display(), e));
	let file_change = replace_region_in_text(&contents, start, end, replace_start, replacements);

	if write_back {
	if let Err(e) = fs::write(path, file_change.new_lines.as_bytes()) {
	panic!("Cannot write to {}: {}", path.display(), e);
	}
	}
	file_change
	}

	/// Replaces a region in a text delimited by two lines matching regexes.
	///
	/// * `text` is the input text on which you want to perform the replacement
	/// * `start` is a `&str` that describes the delimiter line before the region you want to replace.
	/// As the `&str` will be converted to a `Regex`, this can contain regex syntax, too.
	/// * `end` is a `&str` that describes the delimiter line until where the replacement should happen.
	/// As the `&str` will be converted to a `Regex`, this can contain regex syntax, too.
	/// * If `replace_start` is true, the `start` delimiter line is replaced as well. The `end`
	/// delimiter line is never replaced.
	/// * `replacements` is a closure that has to return a `Vec<String>` which contains the new text.
	///
	/// If you want to perform the replacement on files instead of already parsed text,
	/// use `replace_region_in_file`.
	///
	/// # Example
	///
	/// ```
	/// let the_text = "replace_start\nsome text\nthat will be replaced\nreplace_end";
	/// let result =
	/// clippy_dev::replace_region_in_text(the_text, "replace_start", "replace_end", false, \|\| {
	/// vec!["a different".to_string(), "text".to_string()]
	/// })
	/// .new_lines;
	/// assert_eq!("replace_start\na different\ntext\nreplace_end", result);
	/// ```
	pub fn replace_region_in_text<F>(text: &str, start: &str, end: &str, replace_start: bool, replacements: F) -> FileChange
	where
	F: FnOnce() -> Vec<String>,
	{
	let replace_it = replacements();
	let mut in_old_region = false;
	let mut found = false;
	let mut new_lines = vec![];
	let start = Regex::new(start).unwrap();
	let end = Regex::new(end).unwrap();

	for line in text.lines() {
	if in_old_region {
	if end.is_match(line) {
	in_old_region = false;
	new_lines.extend(replace_it.clone());
	new_lines.push(line.to_string());
	}
	} else if start.is_match(line) {
	if !replace_start {
	new_lines.push(line.to_string());
	}
	in_old_region = true;
	found = true;
	} else {
	new_lines.push(line.to_string());
	}
	}

	if !found {
	// This happens if the provided regex in `clippy_dev/src/main.rs` does not match in the
	// given text or file. Most likely this is an error on the programmer's side and the Regex
	// is incorrect.
	eprintln!("error: regex \n{:?}\ndoesn't match. You may have to update it.", start);
	std::process::exit(1);
	}

	let mut new_lines = new_lines.join("\n");
	if text.ends_with('\n') {
	new_lines.push('\n');
	}
	let changed = new_lines != text;
	FileChange { changed, new_lines }
	}

	/// Returns the path to the Clippy project directory
	#[must_use]
	pub fn clippy_project_root() -> PathBuf {
	let current_dir = std::env::current_dir().unwrap();
	for path in current_dir.ancestors() {
	let result = std::fs::read_to_string(path.join("Cargo.toml"));
	if let Err(err) = &result {
	if err.kind() == std::io::ErrorKind::NotFound {
	continue;
	}
	}

	let content = result.unwrap();
	if content.contains("[package]\nname = \"clippy\"") {
	return path.to_path_buf();
	}
	}
	panic!("error: Can't determine root of project. Please run inside a Clippy working dir.");
	}

	#[test]
	fn test_parse_contents() {
	let result: Vec<Lint> = parse_contents(
	r#"
	declare_clippy_lint! {
	pub PTR_ARG,
	style,
	"really long \
	text"
	}

	declare_clippy_lint!{
	pub DOC_MARKDOWN,
	pedantic,
	"single line"
	}

	/// some doc comment
	declare_deprecated_lint! {
	pub SHOULD_ASSERT_EQ,
	"`assert!()` will be more flexible with RFC 2011"
	}
	"#,
	"module_name",
	)
	.collect();

	let expected = vec![
	Lint::new("ptr_arg", "style", "really long text", None, "module_name"),
	Lint::new("doc_markdown", "pedantic", "single line", None, "module_name"),
	Lint::new(
	"should_assert_eq",
	"Deprecated",
	"`assert!()` will be more flexible with RFC 2011",
	Some("`assert!()` will be more flexible with RFC 2011"),
	"module_name",
	),
	];
	assert_eq!(expected, result);
	}

	#[test]
	fn test_replace_region() {
	let text = "\nabc\n123\n789\ndef\nghi";
	let expected = FileChange {
	changed: true,
	new_lines: "\nabc\nhello world\ndef\nghi".to_string(),
	};
	let result = replace_region_in_text(text, r#"^\sabc$"#, r#"^\sdef"#, false, \|\| {
	vec!["hello world".to_string()]
	});
	assert_eq!(expected, result);
	}

	#[test]
	fn test_replace_region_with_start() {
	let text = "\nabc\n123\n789\ndef\nghi";
	let expected = FileChange {
	changed: true,
	new_lines: "\nhello world\ndef\nghi".to_string(),
	};
	let result = replace_region_in_text(text, r#"^\sabc$"#, r#"^\sdef"#, true, \|\| {
	vec!["hello world".to_string()]
	});
	assert_eq!(expected, result);
	}

	#[test]
	fn test_replace_region_no_changes() {
	let text = "123\n456\n789";
	let expected = FileChange {
	changed: false,
	new_lines: "123\n456\n789".to_string(),
	};
	let result = replace_region_in_text(text, r#"^\s123$"#, r#"^\s456"#, false, Vec::new);
	assert_eq!(expected, result);
	}

	#[test]
	fn test_usable_lints() {
	let lints = vec![
	Lint::new("should_assert_eq", "Deprecated", "abc", Some("Reason"), "module_name"),
	Lint::new("should_assert_eq2", "Not Deprecated", "abc", None, "module_name"),
	Lint::new("should_assert_eq2", "internal", "abc", None, "module_name"),
	Lint::new("should_assert_eq2", "internal_style", "abc", None, "module_name"),
	];
	let expected = vec![Lint::new(
	"should_assert_eq2",
	"Not Deprecated",
	"abc",
	None,
	"module_name",
	)];
	assert_eq!(expected, Lint::usable_lints(&lints));
	}

	#[test]
	fn test_by_lint_group() {
	let lints = vec![
	Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
	Lint::new("should_assert_eq2", "group2", "abc", None, "module_name"),
	Lint::new("incorrect_match", "group1", "abc", None, "module_name"),
	];
	let mut expected: HashMap<String, Vec<Lint>> = HashMap::new();
	expected.insert(
	"group1".to_string(),
	vec![
	Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
	Lint::new("incorrect_match", "group1", "abc", None, "module_name"),
	],
	);
	expected.insert(
	"group2".to_string(),
	vec![Lint::new("should_assert_eq2", "group2", "abc", None, "module_name")],
	);
	assert_eq!(expected, Lint::by_lint_group(lints.into_iter()));
	}

	#[test]
	fn test_gen_changelog_lint_list() {
	let lints = vec![
	Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
	Lint::new("should_assert_eq2", "group2", "abc", None, "module_name"),
	];
	let expected = vec![
	format!("[`should_assert_eq`]: {}#should_assert_eq", DOCS_LINK.to_string()),
	format!("[`should_assert_eq2`]: {}#should_assert_eq2", DOCS_LINK.to_string()),
	];
	assert_eq!(expected, gen_changelog_lint_list(lints.iter()));
	}

	#[test]
	fn test_gen_deprecated() {
	let lints = vec![
	Lint::new(
	"should_assert_eq",
	"group1",
	"abc",
	Some("has been superseded by should_assert_eq2"),
	"module_name",
	),
	Lint::new(
	"another_deprecated",
	"group2",
	"abc",
	Some("will be removed"),
	"module_name",
	),
	];
	let expected: Vec<String> = vec![
	" store.register_removed(",
	" \"clippy::should_assert_eq\",",
	" \"has been superseded by should_assert_eq2\",",
	" );",
	" store.register_removed(",
	" \"clippy::another_deprecated\",",
	" \"will be removed\",",
	" );",
	]
	.into_iter()
	.map(String::from)
	.collect();
	assert_eq!(expected, gen_deprecated(lints.iter()));
	}

	#[test]
	#[should_panic]
	fn test_gen_deprecated_fail() {
	let lints = vec![Lint::new("should_assert_eq2", "group2", "abc", None, "module_name")];
	let _ = gen_deprecated(lints.iter());
	}

	#[test]
	fn test_gen_modules_list() {
	let lints = vec![
	Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
	Lint::new("incorrect_stuff", "group3", "abc", None, "another_module"),
	];
	let expected = vec!["mod another_module;".to_string(), "mod module_name;".to_string()];
	assert_eq!(expected, gen_modules_list(lints.iter()));
	}

	#[test]
	fn test_gen_lint_group_list() {
	let lints = vec![
	Lint::new("abc", "group1", "abc", None, "module_name"),
	Lint::new("should_assert_eq", "group1", "abc", None, "module_name"),
	Lint::new("internal", "internal_style", "abc", None, "module_name"),
	];
	let expected = vec![
	" LintId::of(&module_name::ABC),".to_string(),
	" LintId::of(&module_name::INTERNAL),".to_string(),
	" LintId::of(&module_name::SHOULD_ASSERT_EQ),".to_string(),
	];
	assert_eq!(expected, gen_lint_group_list(lints.iter()));
	}