//! Cross-platform path manipulation. //! //! This module provides two types, [`PathBuf`] and [`Path`] (akin to [`String`] //! and [`str`]), for working with paths abstractly. These types are thin wrappers //! around [`OsString`] and [`OsStr`] respectively, meaning that they work directly //! on strings according to the local platform's path syntax. //! //! Paths can be parsed into [`Component`]s by iterating over the structure //! returned by the [`components`] method on [`Path`]. [`Component`]s roughly //! correspond to the substrings between path separators (`/` or `\`). You can //! reconstruct an equivalent path from components with the [`push`] method on //! [`PathBuf`]; note that the paths may differ syntactically by the //! normalization described in the documentation for the [`components`] method. //! //! ## Case sensitivity //! //! Unless otherwise indicated path methods that do not access the filesystem, //! such as [`Path::starts_with`] and [`Path::ends_with`], are case sensitive no //! matter the platform or filesystem. An exception to this is made for Windows //! drive letters. //! //! ## Simple usage //! //! Path manipulation includes both parsing components from slices and building //! new owned paths. //! //! To parse a path, you can create a [`Path`] slice from a [`str`] //! slice and start asking questions: //! //! ``` //! use std::path::Path; //! use std::ffi::OsStr; //! //! let path = Path::new("/tmp/foo/bar.txt"); //! //! let parent = path.parent(); //! assert_eq!(parent, Some(Path::new("/tmp/foo"))); //! //! let file_stem = path.file_stem(); //! assert_eq!(file_stem, Some(OsStr::new("bar"))); //! //! let extension = path.extension(); //! assert_eq!(extension, Some(OsStr::new("txt"))); //! ``` //! //! To build or modify paths, use [`PathBuf`]: //! //! ``` //! use std::path::PathBuf; //! //! // This way works... //! let mut path = PathBuf::from("c:\\"); //! //! path.push("windows"); //! path.push("system32"); //! //! path.set_extension("dll"); //! //! // ... but push is best used if you don't know everything up //! // front. If you do, this way is better: //! let path: PathBuf = ["c:\\", "windows", "system32.dll"].iter().collect(); //! ``` //! //! [`components`]: Path::components //! [`push`]: PathBuf::push #![stable(feature = "rust1", since = "1.0.0")] #![deny(unsafe_op_in_unsafe_fn)] #[cfg(test)] mod tests; use crate::borrow::{Borrow, Cow}; use crate::cmp; use crate::collections::TryReserveError; use crate::error::Error; use crate::fmt; use crate::fs; use crate::hash::{Hash, Hasher}; use crate::io; use crate::iter::{self, FusedIterator}; use crate::ops::{self, Deref}; use crate::rc::Rc; use crate::str::FromStr; use crate::sync::Arc; use crate::ffi::{OsStr, OsString}; use crate::sys; use crate::sys::path::{is_sep_byte, is_verbatim_sep, parse_prefix, MAIN_SEP_STR}; //////////////////////////////////////////////////////////////////////////////// // GENERAL NOTES //////////////////////////////////////////////////////////////////////////////// // // Parsing in this module is done by directly transmuting OsStr to [u8] slices, // taking advantage of the fact that OsStr always encodes ASCII characters // as-is. Eventually, this transmutation should be replaced by direct uses of // OsStr APIs for parsing, but it will take a while for those to become // available. //////////////////////////////////////////////////////////////////////////////// // Windows Prefixes //////////////////////////////////////////////////////////////////////////////// /// Windows path prefixes, e.g., `C:` or `\\server\share`. /// /// Windows uses a variety of path prefix styles, including references to drive /// volumes (like `C:`), network shared folders (like `\\server\share`), and /// others. In addition, some path prefixes are "verbatim" (i.e., prefixed with /// `\\?\`), in which case `/` is *not* treated as a separator and essentially /// no normalization is performed. /// /// # Examples /// /// ``` /// use std::path::{Component, Path, Prefix}; /// use std::path::Prefix::*; /// use std::ffi::OsStr; /// /// fn get_path_prefix(s: &str) -> Prefix { /// let path = Path::new(s); /// match path.components().next().unwrap() { /// Component::Prefix(prefix_component) => prefix_component.kind(), /// _ => panic!(), /// } /// } /// /// # if cfg!(windows) { /// assert_eq!(Verbatim(OsStr::new("pictures")), /// get_path_prefix(r"\\?\pictures\kittens")); /// assert_eq!(VerbatimUNC(OsStr::new("server"), OsStr::new("share")), /// get_path_prefix(r"\\?\UNC\server\share")); /// assert_eq!(VerbatimDisk(b'C'), get_path_prefix(r"\\?\c:\")); /// assert_eq!(DeviceNS(OsStr::new("BrainInterface")), /// get_path_prefix(r"\\.\BrainInterface")); /// assert_eq!(UNC(OsStr::new("server"), OsStr::new("share")), /// get_path_prefix(r"\\server\share")); /// assert_eq!(Disk(b'C'), get_path_prefix(r"C:\Users\Rust\Pictures\Ferris")); /// # } /// ``` #[derive(Copy, Clone, Debug, Hash, PartialOrd, Ord, PartialEq, Eq)] #[stable(feature = "rust1", since = "1.0.0")] pub enum Prefix<'a> { /// Verbatim prefix, e.g., `\\?\cat_pics`. /// /// Verbatim prefixes consist of `\\?\` immediately followed by the given /// component. #[stable(feature = "rust1", since = "1.0.0")] Verbatim(#[stable(feature = "rust1", since = "1.0.0")] &'a OsStr), /// Verbatim prefix using Windows' _**U**niform **N**aming **C**onvention_, /// e.g., `\\?\UNC\server\share`. /// /// Verbatim UNC prefixes consist of `\\?\UNC\` immediately followed by the /// server's hostname and a share name. #[stable(feature = "rust1", since = "1.0.0")] VerbatimUNC( #[stable(feature = "rust1", since = "1.0.0")] &'a OsStr, #[stable(feature = "rust1", since = "1.0.0")] &'a OsStr, ), /// Verbatim disk prefix, e.g., `\\?\C:`. /// /// Verbatim disk prefixes consist of `\\?\` immediately followed by the /// drive letter and `:`. #[stable(feature = "rust1", since = "1.0.0")] VerbatimDisk(#[stable(feature = "rust1", since = "1.0.0")] u8), /// Device namespace prefix, e.g., `\\.\COM42`. /// /// Device namespace prefixes consist of `\\.\` (possibly using `/` /// instead of `\`), immediately followed by the device name. #[stable(feature = "rust1", since = "1.0.0")] DeviceNS(#[stable(feature = "rust1", since = "1.0.0")] &'a OsStr), /// Prefix using Windows' _**U**niform **N**aming **C**onvention_, e.g. /// `\\server\share`. /// /// UNC prefixes consist of the server's hostname and a share name. #[stable(feature = "rust1", since = "1.0.0")] UNC( #[stable(feature = "rust1", since = "1.0.0")] &'a OsStr, #[stable(feature = "rust1", since = "1.0.0")] &'a OsStr, ), /// Prefix `C:` for the given disk drive. #[stable(feature = "rust1", since = "1.0.0")] Disk(#[stable(feature = "rust1", since = "1.0.0")] u8), } impl<'a> Prefix<'a> { #[inline] fn len(&self) -> usize { use self::Prefix::*; fn os_str_len(s: &OsStr) -> usize { s.bytes().len() } match *self { Verbatim(x) => 4 + os_str_len(x), VerbatimUNC(x, y) => { 8 + os_str_len(x) + if os_str_len(y) > 0 { 1 + os_str_len(y) } else { 0 } } VerbatimDisk(_) => 6, UNC(x, y) => 2 + os_str_len(x) + if os_str_len(y) > 0 { 1 + os_str_len(y) } else { 0 }, DeviceNS(x) => 4 + os_str_len(x), Disk(_) => 2, } } /// Determines if the prefix is verbatim, i.e., begins with `\\?\`. /// /// # Examples /// /// ``` /// use std::path::Prefix::*; /// use std::ffi::OsStr; /// /// assert!(Verbatim(OsStr::new("pictures")).is_verbatim()); /// assert!(VerbatimUNC(OsStr::new("server"), OsStr::new("share")).is_verbatim()); /// assert!(VerbatimDisk(b'C').is_verbatim()); /// assert!(!DeviceNS(OsStr::new("BrainInterface")).is_verbatim()); /// assert!(!UNC(OsStr::new("server"), OsStr::new("share")).is_verbatim()); /// assert!(!Disk(b'C').is_verbatim()); /// ``` #[inline] #[must_use] #[stable(feature = "rust1", since = "1.0.0")] pub fn is_verbatim(&self) -> bool { use self::Prefix::*; matches!(*self, Verbatim(_) | VerbatimDisk(_) | VerbatimUNC(..)) } #[inline] fn is_drive(&self) -> bool { matches!(*self, Prefix::Disk(_)) } #[inline] fn has_implicit_root(&self) -> bool { !self.is_drive() } } //////////////////////////////////////////////////////////////////////////////// // Exposed parsing helpers //////////////////////////////////////////////////////////////////////////////// /// Determines whether the character is one of the permitted path /// separators for the current platform. /// /// # Examples /// /// ``` /// use std::path; /// /// assert!(path::is_separator('/')); // '/' works for both Unix and Windows /// assert!(!path::is_separator('❤')); /// ``` #[must_use] #[stable(feature = "rust1", since = "1.0.0")] pub fn is_separator(c: char) -> bool { c.is_ascii() && is_sep_byte(c as u8) } /// The primary separator of path components for the current platform. /// /// For example, `/` on Unix and `\` on Windows. #[stable(feature = "rust1", since = "1.0.0")] pub const MAIN_SEPARATOR: char = crate::sys::path::MAIN_SEP; /// The primary separator of path components for the current platform. /// /// For example, `/` on Unix and `\` on Windows. #[stable(feature = "main_separator_str", since = "1.68.0")] pub const MAIN_SEPARATOR_STR: &str = crate::sys::path::MAIN_SEP_STR; //////////////////////////////////////////////////////////////////////////////// // Misc helpers //////////////////////////////////////////////////////////////////////////////// // Iterate through `iter` while it matches `prefix`; return `None` if `prefix` // is not a prefix of `iter`, otherwise return `Some(iter_after_prefix)` giving // `iter` after having exhausted `prefix`. fn iter_after<'a, 'b, I, J>(mut iter: I, mut prefix: J) -> Option where I: Iterator> + Clone, J: Iterator>, { loop { let mut iter_next = iter.clone(); match (iter_next.next(), prefix.next()) { (Some(ref x), Some(ref y)) if x == y => (), (Some(_), Some(_)) => return None, (Some(_), None) => return Some(iter), (None, None) => return Some(iter), (None, Some(_)) => return None, } iter = iter_next; } } unsafe fn u8_slice_as_os_str(s: &[u8]) -> &OsStr { // SAFETY: See note at the top of this module to understand why this and // `OsStr::bytes` are used: // // This casts are safe as OsStr is internally a wrapper around [u8] on all // platforms. // // Note that currently this relies on the special knowledge that std has; // these types are single-element structs but are not marked // repr(transparent) or repr(C) which would make these casts not allowable // outside std. unsafe { &*(s as *const [u8] as *const OsStr) } } // Detect scheme on Redox fn has_redox_scheme(s: &[u8]) -> bool { cfg!(target_os = "redox") && s.contains(&b':') } //////////////////////////////////////////////////////////////////////////////// // Cross-platform, iterator-independent parsing //////////////////////////////////////////////////////////////////////////////// /// Says whether the first byte after the prefix is a separator. fn has_physical_root(s: &[u8], prefix: Option>) -> bool { let path = if let Some(p) = prefix { &s[p.len()..] } else { s }; !path.is_empty() && is_sep_byte(path[0]) } // basic workhorse for splitting stem and extension fn rsplit_file_at_dot(file: &OsStr) -> (Option<&OsStr>, Option<&OsStr>) { if file.bytes() == b".." { return (Some(file), None); } // The unsafety here stems from converting between &OsStr and &[u8] // and back. This is safe to do because (1) we only look at ASCII // contents of the encoding and (2) new &OsStr values are produced // only from ASCII-bounded slices of existing &OsStr values. let mut iter = file.bytes().rsplitn(2, |b| *b == b'.'); let after = iter.next(); let before = iter.next(); if before == Some(b"") { (Some(file), None) } else { unsafe { (before.map(|s| u8_slice_as_os_str(s)), after.map(|s| u8_slice_as_os_str(s))) } } } fn split_file_at_dot(file: &OsStr) -> (&OsStr, Option<&OsStr>) { let slice = file.bytes(); if slice == b".." { return (file, None); } // The unsafety here stems from converting between &OsStr and &[u8] // and back. This is safe to do because (1) we only look at ASCII // contents of the encoding and (2) new &OsStr values are produced // only from ASCII-bounded slices of existing &OsStr values. let i = match slice[1..].iter().position(|b| *b == b'.') { Some(i) => i + 1, None => return (file, None), }; let before = &slice[..i]; let after = &slice[i + 1..]; unsafe { (u8_slice_as_os_str(before), Some(u8_slice_as_os_str(after))) } } //////////////////////////////////////////////////////////////////////////////// // The core iterators //////////////////////////////////////////////////////////////////////////////// /// Component parsing works by a double-ended state machine; the cursors at the /// front and back of the path each keep track of what parts of the path have /// been consumed so far. /// /// Going front to back, a path is made up of a prefix, a starting /// directory component, and a body (of normal components) #[derive(Copy, Clone, PartialEq, PartialOrd, Debug)] enum State { Prefix = 0, // c: StartDir = 1, // / or . or nothing Body = 2, // foo/bar/baz Done = 3, } /// A structure wrapping a Windows path prefix as well as its unparsed string /// representation. /// /// In addition to the parsed [`Prefix`] information returned by [`kind`], /// `PrefixComponent` also holds the raw and unparsed [`OsStr`] slice, /// returned by [`as_os_str`]. /// /// Instances of this `struct` can be obtained by matching against the /// [`Prefix` variant] on [`Component`]. /// /// Does not occur on Unix. /// /// # Examples /// /// ``` /// # if cfg!(windows) { /// use std::path::{Component, Path, Prefix}; /// use std::ffi::OsStr; /// /// let path = Path::new(r"c:\you\later\"); /// match path.components().next().unwrap() { /// Component::Prefix(prefix_component) => { /// assert_eq!(Prefix::Disk(b'C'), prefix_component.kind()); /// assert_eq!(OsStr::new("c:"), prefix_component.as_os_str()); /// } /// _ => unreachable!(), /// } /// # } /// ``` /// /// [`as_os_str`]: PrefixComponent::as_os_str /// [`kind`]: PrefixComponent::kind /// [`Prefix` variant]: Component::Prefix #[stable(feature = "rust1", since = "1.0.0")] #[derive(Copy, Clone, Eq, Debug)] pub struct PrefixComponent<'a> { /// The prefix as an unparsed `OsStr` slice. raw: &'a OsStr, /// The parsed prefix data. parsed: Prefix<'a>, } impl<'a> PrefixComponent<'a> { /// Returns the parsed prefix data. /// /// See [`Prefix`]'s documentation for more information on the different /// kinds of prefixes. #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[inline] pub fn kind(&self) -> Prefix<'a> { self.parsed } /// Returns the raw [`OsStr`] slice for this prefix. #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[inline] pub fn as_os_str(&self) -> &'a OsStr { self.raw } } #[stable(feature = "rust1", since = "1.0.0")] impl<'a> cmp::PartialEq for PrefixComponent<'a> { #[inline] fn eq(&self, other: &PrefixComponent<'a>) -> bool { cmp::PartialEq::eq(&self.parsed, &other.parsed) } } #[stable(feature = "rust1", since = "1.0.0")] impl<'a> cmp::PartialOrd for PrefixComponent<'a> { #[inline] fn partial_cmp(&self, other: &PrefixComponent<'a>) -> Option { cmp::PartialOrd::partial_cmp(&self.parsed, &other.parsed) } } #[stable(feature = "rust1", since = "1.0.0")] impl cmp::Ord for PrefixComponent<'_> { #[inline] fn cmp(&self, other: &Self) -> cmp::Ordering { cmp::Ord::cmp(&self.parsed, &other.parsed) } } #[stable(feature = "rust1", since = "1.0.0")] impl Hash for PrefixComponent<'_> { fn hash(&self, h: &mut H) { self.parsed.hash(h); } } /// A single component of a path. /// /// A `Component` roughly corresponds to a substring between path separators /// (`/` or `\`). /// /// This `enum` is created by iterating over [`Components`], which in turn is /// created by the [`components`](Path::components) method on [`Path`]. /// /// # Examples /// /// ```rust /// use std::path::{Component, Path}; /// /// let path = Path::new("/tmp/foo/bar.txt"); /// let components = path.components().collect::>(); /// assert_eq!(&components, &[ /// Component::RootDir, /// Component::Normal("tmp".as_ref()), /// Component::Normal("foo".as_ref()), /// Component::Normal("bar.txt".as_ref()), /// ]); /// ``` #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug)] #[stable(feature = "rust1", since = "1.0.0")] pub enum Component<'a> { /// A Windows path prefix, e.g., `C:` or `\\server\share`. /// /// There is a large variety of prefix types, see [`Prefix`]'s documentation /// for more. /// /// Does not occur on Unix. #[stable(feature = "rust1", since = "1.0.0")] Prefix(#[stable(feature = "rust1", since = "1.0.0")] PrefixComponent<'a>), /// The root directory component, appears after any prefix and before anything else. /// /// It represents a separator that designates that a path starts from root. #[stable(feature = "rust1", since = "1.0.0")] RootDir, /// A reference to the current directory, i.e., `.`. #[stable(feature = "rust1", since = "1.0.0")] CurDir, /// A reference to the parent directory, i.e., `..`. #[stable(feature = "rust1", since = "1.0.0")] ParentDir, /// A normal component, e.g., `a` and `b` in `a/b`. /// /// This variant is the most common one, it represents references to files /// or directories. #[stable(feature = "rust1", since = "1.0.0")] Normal(#[stable(feature = "rust1", since = "1.0.0")] &'a OsStr), } impl<'a> Component<'a> { /// Extracts the underlying [`OsStr`] slice. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path = Path::new("./tmp/foo/bar.txt"); /// let components: Vec<_> = path.components().map(|comp| comp.as_os_str()).collect(); /// assert_eq!(&components, &[".", "tmp", "foo", "bar.txt"]); /// ``` #[must_use = "`self` will be dropped if the result is not used"] #[stable(feature = "rust1", since = "1.0.0")] pub fn as_os_str(self) -> &'a OsStr { match self { Component::Prefix(p) => p.as_os_str(), Component::RootDir => OsStr::new(MAIN_SEP_STR), Component::CurDir => OsStr::new("."), Component::ParentDir => OsStr::new(".."), Component::Normal(path) => path, } } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for Component<'_> { #[inline] fn as_ref(&self) -> &OsStr { self.as_os_str() } } #[stable(feature = "path_component_asref", since = "1.25.0")] impl AsRef for Component<'_> { #[inline] fn as_ref(&self) -> &Path { self.as_os_str().as_ref() } } /// An iterator over the [`Component`]s of a [`Path`]. /// /// This `struct` is created by the [`components`] method on [`Path`]. /// See its documentation for more. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path = Path::new("/tmp/foo/bar.txt"); /// /// for component in path.components() { /// println!("{component:?}"); /// } /// ``` /// /// [`components`]: Path::components #[derive(Clone)] #[must_use = "iterators are lazy and do nothing unless consumed"] #[stable(feature = "rust1", since = "1.0.0")] pub struct Components<'a> { // The path left to parse components from path: &'a [u8], // The prefix as it was originally parsed, if any prefix: Option>, // true if path *physically* has a root separator; for most Windows // prefixes, it may have a "logical" root separator for the purposes of // normalization, e.g., \\server\share == \\server\share\. has_physical_root: bool, // The iterator is double-ended, and these two states keep track of what has // been produced from either end front: State, back: State, } /// An iterator over the [`Component`]s of a [`Path`], as [`OsStr`] slices. /// /// This `struct` is created by the [`iter`] method on [`Path`]. /// See its documentation for more. /// /// [`iter`]: Path::iter #[derive(Clone)] #[must_use = "iterators are lazy and do nothing unless consumed"] #[stable(feature = "rust1", since = "1.0.0")] pub struct Iter<'a> { inner: Components<'a>, } #[stable(feature = "path_components_debug", since = "1.13.0")] impl fmt::Debug for Components<'_> { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { struct DebugHelper<'a>(&'a Path); impl fmt::Debug for DebugHelper<'_> { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { f.debug_list().entries(self.0.components()).finish() } } f.debug_tuple("Components").field(&DebugHelper(self.as_path())).finish() } } impl<'a> Components<'a> { // how long is the prefix, if any? #[inline] fn prefix_len(&self) -> usize { self.prefix.as_ref().map(Prefix::len).unwrap_or(0) } #[inline] fn prefix_verbatim(&self) -> bool { self.prefix.as_ref().map(Prefix::is_verbatim).unwrap_or(false) } /// how much of the prefix is left from the point of view of iteration? #[inline] fn prefix_remaining(&self) -> usize { if self.front == State::Prefix { self.prefix_len() } else { 0 } } // Given the iteration so far, how much of the pre-State::Body path is left? #[inline] fn len_before_body(&self) -> usize { let root = if self.front <= State::StartDir && self.has_physical_root { 1 } else { 0 }; let cur_dir = if self.front <= State::StartDir && self.include_cur_dir() { 1 } else { 0 }; self.prefix_remaining() + root + cur_dir } // is the iteration complete? #[inline] fn finished(&self) -> bool { self.front == State::Done || self.back == State::Done || self.front > self.back } #[inline] fn is_sep_byte(&self, b: u8) -> bool { if self.prefix_verbatim() { is_verbatim_sep(b) } else { is_sep_byte(b) } } /// Extracts a slice corresponding to the portion of the path remaining for iteration. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let mut components = Path::new("/tmp/foo/bar.txt").components(); /// components.next(); /// components.next(); /// /// assert_eq!(Path::new("foo/bar.txt"), components.as_path()); /// ``` #[must_use] #[stable(feature = "rust1", since = "1.0.0")] pub fn as_path(&self) -> &'a Path { let mut comps = self.clone(); if comps.front == State::Body { comps.trim_left(); } if comps.back == State::Body { comps.trim_right(); } unsafe { Path::from_u8_slice(comps.path) } } /// Is the *original* path rooted? fn has_root(&self) -> bool { if self.has_physical_root { return true; } if let Some(p) = self.prefix { if p.has_implicit_root() { return true; } } false } /// Should the normalized path include a leading . ? fn include_cur_dir(&self) -> bool { if self.has_root() { return false; } let mut iter = self.path[self.prefix_remaining()..].iter(); match (iter.next(), iter.next()) { (Some(&b'.'), None) => true, (Some(&b'.'), Some(&b)) => self.is_sep_byte(b), _ => false, } } // parse a given byte sequence into the corresponding path component fn parse_single_component<'b>(&self, comp: &'b [u8]) -> Option> { match comp { b"." if self.prefix_verbatim() => Some(Component::CurDir), b"." => None, // . components are normalized away, except at // the beginning of a path, which is treated // separately via `include_cur_dir` b".." => Some(Component::ParentDir), b"" => None, _ => Some(Component::Normal(unsafe { u8_slice_as_os_str(comp) })), } } // parse a component from the left, saying how many bytes to consume to // remove the component fn parse_next_component(&self) -> (usize, Option>) { debug_assert!(self.front == State::Body); let (extra, comp) = match self.path.iter().position(|b| self.is_sep_byte(*b)) { None => (0, self.path), Some(i) => (1, &self.path[..i]), }; (comp.len() + extra, self.parse_single_component(comp)) } // parse a component from the right, saying how many bytes to consume to // remove the component fn parse_next_component_back(&self) -> (usize, Option>) { debug_assert!(self.back == State::Body); let start = self.len_before_body(); let (extra, comp) = match self.path[start..].iter().rposition(|b| self.is_sep_byte(*b)) { None => (0, &self.path[start..]), Some(i) => (1, &self.path[start + i + 1..]), }; (comp.len() + extra, self.parse_single_component(comp)) } // trim away repeated separators (i.e., empty components) on the left fn trim_left(&mut self) { while !self.path.is_empty() { let (size, comp) = self.parse_next_component(); if comp.is_some() { return; } else { self.path = &self.path[size..]; } } } // trim away repeated separators (i.e., empty components) on the right fn trim_right(&mut self) { while self.path.len() > self.len_before_body() { let (size, comp) = self.parse_next_component_back(); if comp.is_some() { return; } else { self.path = &self.path[..self.path.len() - size]; } } } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for Components<'_> { #[inline] fn as_ref(&self) -> &Path { self.as_path() } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for Components<'_> { #[inline] fn as_ref(&self) -> &OsStr { self.as_path().as_os_str() } } #[stable(feature = "path_iter_debug", since = "1.13.0")] impl fmt::Debug for Iter<'_> { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { struct DebugHelper<'a>(&'a Path); impl fmt::Debug for DebugHelper<'_> { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { f.debug_list().entries(self.0.iter()).finish() } } f.debug_tuple("Iter").field(&DebugHelper(self.as_path())).finish() } } impl<'a> Iter<'a> { /// Extracts a slice corresponding to the portion of the path remaining for iteration. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let mut iter = Path::new("/tmp/foo/bar.txt").iter(); /// iter.next(); /// iter.next(); /// /// assert_eq!(Path::new("foo/bar.txt"), iter.as_path()); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[inline] pub fn as_path(&self) -> &'a Path { self.inner.as_path() } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for Iter<'_> { #[inline] fn as_ref(&self) -> &Path { self.as_path() } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for Iter<'_> { #[inline] fn as_ref(&self) -> &OsStr { self.as_path().as_os_str() } } #[stable(feature = "rust1", since = "1.0.0")] impl<'a> Iterator for Iter<'a> { type Item = &'a OsStr; #[inline] fn next(&mut self) -> Option<&'a OsStr> { self.inner.next().map(Component::as_os_str) } } #[stable(feature = "rust1", since = "1.0.0")] impl<'a> DoubleEndedIterator for Iter<'a> { #[inline] fn next_back(&mut self) -> Option<&'a OsStr> { self.inner.next_back().map(Component::as_os_str) } } #[stable(feature = "fused", since = "1.26.0")] impl FusedIterator for Iter<'_> {} #[stable(feature = "rust1", since = "1.0.0")] impl<'a> Iterator for Components<'a> { type Item = Component<'a>; fn next(&mut self) -> Option> { while !self.finished() { match self.front { State::Prefix if self.prefix_len() > 0 => { self.front = State::StartDir; debug_assert!(self.prefix_len() <= self.path.len()); let raw = &self.path[..self.prefix_len()]; self.path = &self.path[self.prefix_len()..]; return Some(Component::Prefix(PrefixComponent { raw: unsafe { u8_slice_as_os_str(raw) }, parsed: self.prefix.unwrap(), })); } State::Prefix => { self.front = State::StartDir; } State::StartDir => { self.front = State::Body; if self.has_physical_root { debug_assert!(!self.path.is_empty()); self.path = &self.path[1..]; return Some(Component::RootDir); } else if let Some(p) = self.prefix { if p.has_implicit_root() && !p.is_verbatim() { return Some(Component::RootDir); } } else if self.include_cur_dir() { debug_assert!(!self.path.is_empty()); self.path = &self.path[1..]; return Some(Component::CurDir); } } State::Body if !self.path.is_empty() => { let (size, comp) = self.parse_next_component(); self.path = &self.path[size..]; if comp.is_some() { return comp; } } State::Body => { self.front = State::Done; } State::Done => unreachable!(), } } None } } #[stable(feature = "rust1", since = "1.0.0")] impl<'a> DoubleEndedIterator for Components<'a> { fn next_back(&mut self) -> Option> { while !self.finished() { match self.back { State::Body if self.path.len() > self.len_before_body() => { let (size, comp) = self.parse_next_component_back(); self.path = &self.path[..self.path.len() - size]; if comp.is_some() { return comp; } } State::Body => { self.back = State::StartDir; } State::StartDir => { self.back = State::Prefix; if self.has_physical_root { self.path = &self.path[..self.path.len() - 1]; return Some(Component::RootDir); } else if let Some(p) = self.prefix { if p.has_implicit_root() && !p.is_verbatim() { return Some(Component::RootDir); } } else if self.include_cur_dir() { self.path = &self.path[..self.path.len() - 1]; return Some(Component::CurDir); } } State::Prefix if self.prefix_len() > 0 => { self.back = State::Done; return Some(Component::Prefix(PrefixComponent { raw: unsafe { u8_slice_as_os_str(self.path) }, parsed: self.prefix.unwrap(), })); } State::Prefix => { self.back = State::Done; return None; } State::Done => unreachable!(), } } None } } #[stable(feature = "fused", since = "1.26.0")] impl FusedIterator for Components<'_> {} #[stable(feature = "rust1", since = "1.0.0")] impl<'a> cmp::PartialEq for Components<'a> { #[inline] fn eq(&self, other: &Components<'a>) -> bool { let Components { path: _, front: _, back: _, has_physical_root: _, prefix: _ } = self; // Fast path for exact matches, e.g. for hashmap lookups. // Don't explicitly compare the prefix or has_physical_root fields since they'll // either be covered by the `path` buffer or are only relevant for `prefix_verbatim()`. if self.path.len() == other.path.len() && self.front == other.front && self.back == State::Body && other.back == State::Body && self.prefix_verbatim() == other.prefix_verbatim() { // possible future improvement: this could bail out earlier if there were a // reverse memcmp/bcmp comparing back to front if self.path == other.path { return true; } } // compare back to front since absolute paths often share long prefixes Iterator::eq(self.clone().rev(), other.clone().rev()) } } #[stable(feature = "rust1", since = "1.0.0")] impl cmp::Eq for Components<'_> {} #[stable(feature = "rust1", since = "1.0.0")] impl<'a> cmp::PartialOrd for Components<'a> { #[inline] fn partial_cmp(&self, other: &Components<'a>) -> Option { Some(compare_components(self.clone(), other.clone())) } } #[stable(feature = "rust1", since = "1.0.0")] impl cmp::Ord for Components<'_> { #[inline] fn cmp(&self, other: &Self) -> cmp::Ordering { compare_components(self.clone(), other.clone()) } } fn compare_components(mut left: Components<'_>, mut right: Components<'_>) -> cmp::Ordering { // Fast path for long shared prefixes // // - compare raw bytes to find first mismatch // - backtrack to find separator before mismatch to avoid ambiguous parsings of '.' or '..' characters // - if found update state to only do a component-wise comparison on the remainder, // otherwise do it on the full path // // The fast path isn't taken for paths with a PrefixComponent to avoid backtracking into // the middle of one if left.prefix.is_none() && right.prefix.is_none() && left.front == right.front { // possible future improvement: a [u8]::first_mismatch simd implementation let first_difference = match left.path.iter().zip(right.path).position(|(&a, &b)| a != b) { None if left.path.len() == right.path.len() => return cmp::Ordering::Equal, None => left.path.len().min(right.path.len()), Some(diff) => diff, }; if let Some(previous_sep) = left.path[..first_difference].iter().rposition(|&b| left.is_sep_byte(b)) { let mismatched_component_start = previous_sep + 1; left.path = &left.path[mismatched_component_start..]; left.front = State::Body; right.path = &right.path[mismatched_component_start..]; right.front = State::Body; } } Iterator::cmp(left, right) } /// An iterator over [`Path`] and its ancestors. /// /// This `struct` is created by the [`ancestors`] method on [`Path`]. /// See its documentation for more. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path = Path::new("/foo/bar"); /// /// for ancestor in path.ancestors() { /// println!("{}", ancestor.display()); /// } /// ``` /// /// [`ancestors`]: Path::ancestors #[derive(Copy, Clone, Debug)] #[must_use = "iterators are lazy and do nothing unless consumed"] #[stable(feature = "path_ancestors", since = "1.28.0")] pub struct Ancestors<'a> { next: Option<&'a Path>, } #[stable(feature = "path_ancestors", since = "1.28.0")] impl<'a> Iterator for Ancestors<'a> { type Item = &'a Path; #[inline] fn next(&mut self) -> Option { let next = self.next; self.next = next.and_then(Path::parent); next } } #[stable(feature = "path_ancestors", since = "1.28.0")] impl FusedIterator for Ancestors<'_> {} //////////////////////////////////////////////////////////////////////////////// // Basic types and traits //////////////////////////////////////////////////////////////////////////////// /// An owned, mutable path (akin to [`String`]). /// /// This type provides methods like [`push`] and [`set_extension`] that mutate /// the path in place. It also implements [`Deref`] to [`Path`], meaning that /// all methods on [`Path`] slices are available on `PathBuf` values as well. /// /// [`push`]: PathBuf::push /// [`set_extension`]: PathBuf::set_extension /// /// More details about the overall approach can be found in /// the [module documentation](self). /// /// # Examples /// /// You can use [`push`] to build up a `PathBuf` from /// components: /// /// ``` /// use std::path::PathBuf; /// /// let mut path = PathBuf::new(); /// /// path.push(r"C:\"); /// path.push("windows"); /// path.push("system32"); /// /// path.set_extension("dll"); /// ``` /// /// However, [`push`] is best used for dynamic situations. This is a better way /// to do this when you know all of the components ahead of time: /// /// ``` /// use std::path::PathBuf; /// /// let path: PathBuf = [r"C:\", "windows", "system32.dll"].iter().collect(); /// ``` /// /// We can still do better than this! Since these are all strings, we can use /// `From::from`: /// /// ``` /// use std::path::PathBuf; /// /// let path = PathBuf::from(r"C:\windows\system32.dll"); /// ``` /// /// Which method works best depends on what kind of situation you're in. #[cfg_attr(not(test), rustc_diagnostic_item = "PathBuf")] #[stable(feature = "rust1", since = "1.0.0")] // FIXME: // `PathBuf::as_mut_vec` current implementation relies // on `PathBuf` being layout-compatible with `Vec`. // When attribute privacy is implemented, `PathBuf` should be annotated as `#[repr(transparent)]`. // Anyway, `PathBuf` representation and layout are considered implementation detail, are // not documented and must not be relied upon. pub struct PathBuf { inner: OsString, } impl PathBuf { #[inline] fn as_mut_vec(&mut self) -> &mut Vec { unsafe { &mut *(self as *mut PathBuf as *mut Vec) } } /// Allocates an empty `PathBuf`. /// /// # Examples /// /// ``` /// use std::path::PathBuf; /// /// let path = PathBuf::new(); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[inline] pub fn new() -> PathBuf { PathBuf { inner: OsString::new() } } /// Creates a new `PathBuf` with a given capacity used to create the /// internal [`OsString`]. See [`with_capacity`] defined on [`OsString`]. /// /// # Examples /// /// ``` /// use std::path::PathBuf; /// /// let mut path = PathBuf::with_capacity(10); /// let capacity = path.capacity(); /// /// // This push is done without reallocating /// path.push(r"C:\"); /// /// assert_eq!(capacity, path.capacity()); /// ``` /// /// [`with_capacity`]: OsString::with_capacity #[stable(feature = "path_buf_capacity", since = "1.44.0")] #[must_use] #[inline] pub fn with_capacity(capacity: usize) -> PathBuf { PathBuf { inner: OsString::with_capacity(capacity) } } /// Coerces to a [`Path`] slice. /// /// # Examples /// /// ``` /// use std::path::{Path, PathBuf}; /// /// let p = PathBuf::from("/test"); /// assert_eq!(Path::new("/test"), p.as_path()); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[inline] pub fn as_path(&self) -> &Path { self } /// Extends `self` with `path`. /// /// If `path` is absolute, it replaces the current path. /// /// On Windows: /// /// * if `path` has a root but no prefix (e.g., `\windows`), it /// replaces everything except for the prefix (if any) of `self`. /// * if `path` has a prefix but no root, it replaces `self`. /// * if `self` has a verbatim prefix (e.g. `\\?\C:\windows`) /// and `path` is not empty, the new path is normalized: all references /// to `.` and `..` are removed. /// /// Consider using [`Path::join`] if you need a new `PathBuf` instead of /// using this function on a cloned `PathBuf`. /// /// # Examples /// /// Pushing a relative path extends the existing path: /// /// ``` /// use std::path::PathBuf; /// /// let mut path = PathBuf::from("/tmp"); /// path.push("file.bk"); /// assert_eq!(path, PathBuf::from("/tmp/file.bk")); /// ``` /// /// Pushing an absolute path replaces the existing path: /// /// ``` /// use std::path::PathBuf; /// /// let mut path = PathBuf::from("/tmp"); /// path.push("/etc"); /// assert_eq!(path, PathBuf::from("/etc")); /// ``` #[stable(feature = "rust1", since = "1.0.0")] pub fn push>(&mut self, path: P) { self._push(path.as_ref()) } fn _push(&mut self, path: &Path) { // in general, a separator is needed if the rightmost byte is not a separator let mut need_sep = self.as_mut_vec().last().map(|c| !is_sep_byte(*c)).unwrap_or(false); // in the special case of `C:` on Windows, do *not* add a separator let comps = self.components(); if comps.prefix_len() > 0 && comps.prefix_len() == comps.path.len() && comps.prefix.unwrap().is_drive() { need_sep = false } // absolute `path` replaces `self` if path.is_absolute() || path.prefix().is_some() { self.as_mut_vec().truncate(0); // verbatim paths need . and .. removed } else if comps.prefix_verbatim() && !path.inner.is_empty() { let mut buf: Vec<_> = comps.collect(); for c in path.components() { match c { Component::RootDir => { buf.truncate(1); buf.push(c); } Component::CurDir => (), Component::ParentDir => { if let Some(Component::Normal(_)) = buf.last() { buf.pop(); } } _ => buf.push(c), } } let mut res = OsString::new(); let mut need_sep = false; for c in buf { if need_sep && c != Component::RootDir { res.push(MAIN_SEP_STR); } res.push(c.as_os_str()); need_sep = match c { Component::RootDir => false, Component::Prefix(prefix) => { !prefix.parsed.is_drive() && prefix.parsed.len() > 0 } _ => true, } } self.inner = res; return; // `path` has a root but no prefix, e.g., `\windows` (Windows only) } else if path.has_root() { let prefix_len = self.components().prefix_remaining(); self.as_mut_vec().truncate(prefix_len); // `path` is a pure relative path } else if need_sep { self.inner.push(MAIN_SEP_STR); } self.inner.push(path); } /// Truncates `self` to [`self.parent`]. /// /// Returns `false` and does nothing if [`self.parent`] is [`None`]. /// Otherwise, returns `true`. /// /// [`self.parent`]: Path::parent /// /// # Examples /// /// ``` /// use std::path::{Path, PathBuf}; /// /// let mut p = PathBuf::from("/spirited/away.rs"); /// /// p.pop(); /// assert_eq!(Path::new("/spirited"), p); /// p.pop(); /// assert_eq!(Path::new("/"), p); /// ``` #[stable(feature = "rust1", since = "1.0.0")] pub fn pop(&mut self) -> bool { match self.parent().map(|p| p.as_u8_slice().len()) { Some(len) => { self.as_mut_vec().truncate(len); true } None => false, } } /// Updates [`self.file_name`] to `file_name`. /// /// If [`self.file_name`] was [`None`], this is equivalent to pushing /// `file_name`. /// /// Otherwise it is equivalent to calling [`pop`] and then pushing /// `file_name`. The new path will be a sibling of the original path. /// (That is, it will have the same parent.) /// /// [`self.file_name`]: Path::file_name /// [`pop`]: PathBuf::pop /// /// # Examples /// /// ``` /// use std::path::PathBuf; /// /// let mut buf = PathBuf::from("/"); /// assert!(buf.file_name() == None); /// buf.set_file_name("bar"); /// assert!(buf == PathBuf::from("/bar")); /// assert!(buf.file_name().is_some()); /// buf.set_file_name("baz.txt"); /// assert!(buf == PathBuf::from("/baz.txt")); /// ``` #[stable(feature = "rust1", since = "1.0.0")] pub fn set_file_name>(&mut self, file_name: S) { self._set_file_name(file_name.as_ref()) } fn _set_file_name(&mut self, file_name: &OsStr) { if self.file_name().is_some() { let popped = self.pop(); debug_assert!(popped); } self.push(file_name); } /// Updates [`self.extension`] to `Some(extension)` or to `None` if /// `extension` is empty. /// /// Returns `false` and does nothing if [`self.file_name`] is [`None`], /// returns `true` and updates the extension otherwise. /// /// If [`self.extension`] is [`None`], the extension is added; otherwise /// it is replaced. /// /// If `extension` is the empty string, [`self.extension`] will be [`None`] /// afterwards, not `Some("")`. /// /// # Caveats /// /// The new `extension` may contain dots and will be used in its entirety, /// but only the part after the final dot will be reflected in /// [`self.extension`]. /// /// If the file stem contains internal dots and `extension` is empty, part /// of the old file stem will be considered the new [`self.extension`]. /// /// See the examples below. /// /// [`self.file_name`]: Path::file_name /// [`self.extension`]: Path::extension /// /// # Examples /// /// ``` /// use std::path::{Path, PathBuf}; /// /// let mut p = PathBuf::from("/feel/the"); /// /// p.set_extension("force"); /// assert_eq!(Path::new("/feel/the.force"), p.as_path()); /// /// p.set_extension("dark.side"); /// assert_eq!(Path::new("/feel/the.dark.side"), p.as_path()); /// /// p.set_extension("cookie"); /// assert_eq!(Path::new("/feel/the.dark.cookie"), p.as_path()); /// /// p.set_extension(""); /// assert_eq!(Path::new("/feel/the.dark"), p.as_path()); /// /// p.set_extension(""); /// assert_eq!(Path::new("/feel/the"), p.as_path()); /// /// p.set_extension(""); /// assert_eq!(Path::new("/feel/the"), p.as_path()); /// ``` #[stable(feature = "rust1", since = "1.0.0")] pub fn set_extension>(&mut self, extension: S) -> bool { self._set_extension(extension.as_ref()) } fn _set_extension(&mut self, extension: &OsStr) -> bool { let file_stem = match self.file_stem() { None => return false, Some(f) => f.bytes(), }; // truncate until right after the file stem let end_file_stem = file_stem[file_stem.len()..].as_ptr().addr(); let start = self.inner.bytes().as_ptr().addr(); let v = self.as_mut_vec(); v.truncate(end_file_stem.wrapping_sub(start)); // add the new extension, if any let new = extension.bytes(); if !new.is_empty() { v.reserve_exact(new.len() + 1); v.push(b'.'); v.extend_from_slice(new); } true } /// Yields a mutable reference to the underlying [`OsString`] instance. /// /// # Examples /// /// ``` /// #![feature(path_as_mut_os_str)] /// use std::path::{Path, PathBuf}; /// /// let mut path = PathBuf::from("/foo"); /// /// path.push("bar"); /// assert_eq!(path, Path::new("/foo/bar")); /// /// // OsString's `push` does not add a separator. /// path.as_mut_os_string().push("baz"); /// assert_eq!(path, Path::new("/foo/barbaz")); /// ``` #[unstable(feature = "path_as_mut_os_str", issue = "105021")] #[must_use] #[inline] pub fn as_mut_os_string(&mut self) -> &mut OsString { &mut self.inner } /// Consumes the `PathBuf`, yielding its internal [`OsString`] storage. /// /// # Examples /// /// ``` /// use std::path::PathBuf; /// /// let p = PathBuf::from("/the/head"); /// let os_str = p.into_os_string(); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use = "`self` will be dropped if the result is not used"] #[inline] pub fn into_os_string(self) -> OsString { self.inner } /// Converts this `PathBuf` into a [boxed](Box) [`Path`]. #[stable(feature = "into_boxed_path", since = "1.20.0")] #[must_use = "`self` will be dropped if the result is not used"] #[inline] pub fn into_boxed_path(self) -> Box { let rw = Box::into_raw(self.inner.into_boxed_os_str()) as *mut Path; unsafe { Box::from_raw(rw) } } /// Invokes [`capacity`] on the underlying instance of [`OsString`]. /// /// [`capacity`]: OsString::capacity #[stable(feature = "path_buf_capacity", since = "1.44.0")] #[must_use] #[inline] pub fn capacity(&self) -> usize { self.inner.capacity() } /// Invokes [`clear`] on the underlying instance of [`OsString`]. /// /// [`clear`]: OsString::clear #[stable(feature = "path_buf_capacity", since = "1.44.0")] #[inline] pub fn clear(&mut self) { self.inner.clear() } /// Invokes [`reserve`] on the underlying instance of [`OsString`]. /// /// [`reserve`]: OsString::reserve #[stable(feature = "path_buf_capacity", since = "1.44.0")] #[inline] pub fn reserve(&mut self, additional: usize) { self.inner.reserve(additional) } /// Invokes [`try_reserve`] on the underlying instance of [`OsString`]. /// /// [`try_reserve`]: OsString::try_reserve #[stable(feature = "try_reserve_2", since = "1.63.0")] #[inline] pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> { self.inner.try_reserve(additional) } /// Invokes [`reserve_exact`] on the underlying instance of [`OsString`]. /// /// [`reserve_exact`]: OsString::reserve_exact #[stable(feature = "path_buf_capacity", since = "1.44.0")] #[inline] pub fn reserve_exact(&mut self, additional: usize) { self.inner.reserve_exact(additional) } /// Invokes [`try_reserve_exact`] on the underlying instance of [`OsString`]. /// /// [`try_reserve_exact`]: OsString::try_reserve_exact #[stable(feature = "try_reserve_2", since = "1.63.0")] #[inline] pub fn try_reserve_exact(&mut self, additional: usize) -> Result<(), TryReserveError> { self.inner.try_reserve_exact(additional) } /// Invokes [`shrink_to_fit`] on the underlying instance of [`OsString`]. /// /// [`shrink_to_fit`]: OsString::shrink_to_fit #[stable(feature = "path_buf_capacity", since = "1.44.0")] #[inline] pub fn shrink_to_fit(&mut self) { self.inner.shrink_to_fit() } /// Invokes [`shrink_to`] on the underlying instance of [`OsString`]. /// /// [`shrink_to`]: OsString::shrink_to #[stable(feature = "shrink_to", since = "1.56.0")] #[inline] pub fn shrink_to(&mut self, min_capacity: usize) { self.inner.shrink_to(min_capacity) } } #[stable(feature = "rust1", since = "1.0.0")] impl Clone for PathBuf { #[inline] fn clone(&self) -> Self { PathBuf { inner: self.inner.clone() } } #[inline] fn clone_from(&mut self, source: &Self) { self.inner.clone_from(&source.inner) } } #[stable(feature = "box_from_path", since = "1.17.0")] impl From<&Path> for Box { /// Creates a boxed [`Path`] from a reference. /// /// This will allocate and clone `path` to it. fn from(path: &Path) -> Box { let boxed: Box = path.inner.into(); let rw = Box::into_raw(boxed) as *mut Path; unsafe { Box::from_raw(rw) } } } #[stable(feature = "box_from_cow", since = "1.45.0")] impl From> for Box { /// Creates a boxed [`Path`] from a clone-on-write pointer. /// /// Converting from a `Cow::Owned` does not clone or allocate. #[inline] fn from(cow: Cow<'_, Path>) -> Box { match cow { Cow::Borrowed(path) => Box::from(path), Cow::Owned(path) => Box::from(path), } } } #[stable(feature = "path_buf_from_box", since = "1.18.0")] impl From> for PathBuf { /// Converts a [Box]<[Path]> into a [`PathBuf`]. /// /// This conversion does not allocate or copy memory. #[inline] fn from(boxed: Box) -> PathBuf { boxed.into_path_buf() } } #[stable(feature = "box_from_path_buf", since = "1.20.0")] impl From for Box { /// Converts a [`PathBuf`] into a [Box]<[Path]>. /// /// This conversion currently should not allocate memory, /// but this behavior is not guaranteed on all platforms or in all future versions. #[inline] fn from(p: PathBuf) -> Box { p.into_boxed_path() } } #[stable(feature = "more_box_slice_clone", since = "1.29.0")] impl Clone for Box { #[inline] fn clone(&self) -> Self { self.to_path_buf().into_boxed_path() } } #[stable(feature = "rust1", since = "1.0.0")] impl> From<&T> for PathBuf { /// Converts a borrowed [`OsStr`] to a [`PathBuf`]. /// /// Allocates a [`PathBuf`] and copies the data into it. #[inline] fn from(s: &T) -> PathBuf { PathBuf::from(s.as_ref().to_os_string()) } } #[stable(feature = "rust1", since = "1.0.0")] impl From for PathBuf { /// Converts an [`OsString`] into a [`PathBuf`] /// /// This conversion does not allocate or copy memory. #[inline] fn from(s: OsString) -> PathBuf { PathBuf { inner: s } } } #[stable(feature = "from_path_buf_for_os_string", since = "1.14.0")] impl From for OsString { /// Converts a [`PathBuf`] into an [`OsString`] /// /// This conversion does not allocate or copy memory. #[inline] fn from(path_buf: PathBuf) -> OsString { path_buf.inner } } #[stable(feature = "rust1", since = "1.0.0")] impl From for PathBuf { /// Converts a [`String`] into a [`PathBuf`] /// /// This conversion does not allocate or copy memory. #[inline] fn from(s: String) -> PathBuf { PathBuf::from(OsString::from(s)) } } #[stable(feature = "path_from_str", since = "1.32.0")] impl FromStr for PathBuf { type Err = core::convert::Infallible; #[inline] fn from_str(s: &str) -> Result { Ok(PathBuf::from(s)) } } #[stable(feature = "rust1", since = "1.0.0")] impl> iter::FromIterator

for PathBuf { fn from_iter>(iter: I) -> PathBuf { let mut buf = PathBuf::new(); buf.extend(iter); buf } } #[stable(feature = "rust1", since = "1.0.0")] impl> iter::Extend

for PathBuf { fn extend>(&mut self, iter: I) { iter.into_iter().for_each(move |p| self.push(p.as_ref())); } #[inline] fn extend_one(&mut self, p: P) { self.push(p.as_ref()); } } #[stable(feature = "rust1", since = "1.0.0")] impl fmt::Debug for PathBuf { fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { fmt::Debug::fmt(&**self, formatter) } } #[stable(feature = "rust1", since = "1.0.0")] impl ops::Deref for PathBuf { type Target = Path; #[inline] fn deref(&self) -> &Path { Path::new(&self.inner) } } #[stable(feature = "path_buf_deref_mut", since = "1.68.0")] impl ops::DerefMut for PathBuf { #[inline] fn deref_mut(&mut self) -> &mut Path { Path::from_inner_mut(&mut self.inner) } } #[stable(feature = "rust1", since = "1.0.0")] impl Borrow for PathBuf { #[inline] fn borrow(&self) -> &Path { self.deref() } } #[stable(feature = "default_for_pathbuf", since = "1.17.0")] impl Default for PathBuf { #[inline] fn default() -> Self { PathBuf::new() } } #[stable(feature = "cow_from_path", since = "1.6.0")] impl<'a> From<&'a Path> for Cow<'a, Path> { /// Creates a clone-on-write pointer from a reference to /// [`Path`]. /// /// This conversion does not clone or allocate. #[inline] fn from(s: &'a Path) -> Cow<'a, Path> { Cow::Borrowed(s) } } #[stable(feature = "cow_from_path", since = "1.6.0")] impl<'a> From for Cow<'a, Path> { /// Creates a clone-on-write pointer from an owned /// instance of [`PathBuf`]. /// /// This conversion does not clone or allocate. #[inline] fn from(s: PathBuf) -> Cow<'a, Path> { Cow::Owned(s) } } #[stable(feature = "cow_from_pathbuf_ref", since = "1.28.0")] impl<'a> From<&'a PathBuf> for Cow<'a, Path> { /// Creates a clone-on-write pointer from a reference to /// [`PathBuf`]. /// /// This conversion does not clone or allocate. #[inline] fn from(p: &'a PathBuf) -> Cow<'a, Path> { Cow::Borrowed(p.as_path()) } } #[stable(feature = "pathbuf_from_cow_path", since = "1.28.0")] impl<'a> From> for PathBuf { /// Converts a clone-on-write pointer to an owned path. /// /// Converting from a `Cow::Owned` does not clone or allocate. #[inline] fn from(p: Cow<'a, Path>) -> Self { p.into_owned() } } #[stable(feature = "shared_from_slice2", since = "1.24.0")] impl From for Arc { /// Converts a [`PathBuf`] into an [Arc]<[Path]> by moving the [`PathBuf`] data /// into a new [`Arc`] buffer. #[inline] fn from(s: PathBuf) -> Arc { let arc: Arc = Arc::from(s.into_os_string()); unsafe { Arc::from_raw(Arc::into_raw(arc) as *const Path) } } } #[stable(feature = "shared_from_slice2", since = "1.24.0")] impl From<&Path> for Arc { /// Converts a [`Path`] into an [`Arc`] by copying the [`Path`] data into a new [`Arc`] buffer. #[inline] fn from(s: &Path) -> Arc { let arc: Arc = Arc::from(s.as_os_str()); unsafe { Arc::from_raw(Arc::into_raw(arc) as *const Path) } } } #[stable(feature = "shared_from_slice2", since = "1.24.0")] impl From for Rc { /// Converts a [`PathBuf`] into an [Rc]<[Path]> by moving the [`PathBuf`] data into /// a new [`Rc`] buffer. #[inline] fn from(s: PathBuf) -> Rc { let rc: Rc = Rc::from(s.into_os_string()); unsafe { Rc::from_raw(Rc::into_raw(rc) as *const Path) } } } #[stable(feature = "shared_from_slice2", since = "1.24.0")] impl From<&Path> for Rc { /// Converts a [`Path`] into an [`Rc`] by copying the [`Path`] data into a new [`Rc`] buffer. #[inline] fn from(s: &Path) -> Rc { let rc: Rc = Rc::from(s.as_os_str()); unsafe { Rc::from_raw(Rc::into_raw(rc) as *const Path) } } } #[stable(feature = "rust1", since = "1.0.0")] impl ToOwned for Path { type Owned = PathBuf; #[inline] fn to_owned(&self) -> PathBuf { self.to_path_buf() } #[inline] fn clone_into(&self, target: &mut PathBuf) { self.inner.clone_into(&mut target.inner); } } #[stable(feature = "rust1", since = "1.0.0")] impl cmp::PartialEq for PathBuf { #[inline] fn eq(&self, other: &PathBuf) -> bool { self.components() == other.components() } } #[stable(feature = "rust1", since = "1.0.0")] impl Hash for PathBuf { fn hash(&self, h: &mut H) { self.as_path().hash(h) } } #[stable(feature = "rust1", since = "1.0.0")] impl cmp::Eq for PathBuf {} #[stable(feature = "rust1", since = "1.0.0")] impl cmp::PartialOrd for PathBuf { #[inline] fn partial_cmp(&self, other: &PathBuf) -> Option { Some(compare_components(self.components(), other.components())) } } #[stable(feature = "rust1", since = "1.0.0")] impl cmp::Ord for PathBuf { #[inline] fn cmp(&self, other: &PathBuf) -> cmp::Ordering { compare_components(self.components(), other.components()) } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for PathBuf { #[inline] fn as_ref(&self) -> &OsStr { &self.inner[..] } } /// A slice of a path (akin to [`str`]). /// /// This type supports a number of operations for inspecting a path, including /// breaking the path into its components (separated by `/` on Unix and by either /// `/` or `\` on Windows), extracting the file name, determining whether the path /// is absolute, and so on. /// /// This is an *unsized* type, meaning that it must always be used behind a /// pointer like `&` or [`Box`]. For an owned version of this type, /// see [`PathBuf`]. /// /// More details about the overall approach can be found in /// the [module documentation](self). /// /// # Examples /// /// ``` /// use std::path::Path; /// use std::ffi::OsStr; /// /// // Note: this example does work on Windows /// let path = Path::new("./foo/bar.txt"); /// /// let parent = path.parent(); /// assert_eq!(parent, Some(Path::new("./foo"))); /// /// let file_stem = path.file_stem(); /// assert_eq!(file_stem, Some(OsStr::new("bar"))); /// /// let extension = path.extension(); /// assert_eq!(extension, Some(OsStr::new("txt"))); /// ``` #[cfg_attr(not(test), rustc_diagnostic_item = "Path")] #[stable(feature = "rust1", since = "1.0.0")] // FIXME: // `Path::new` current implementation relies // on `Path` being layout-compatible with `OsStr`. // When attribute privacy is implemented, `Path` should be annotated as `#[repr(transparent)]`. // Anyway, `Path` representation and layout are considered implementation detail, are // not documented and must not be relied upon. pub struct Path { inner: OsStr, } /// An error returned from [`Path::strip_prefix`] if the prefix was not found. /// /// This `struct` is created by the [`strip_prefix`] method on [`Path`]. /// See its documentation for more. /// /// [`strip_prefix`]: Path::strip_prefix #[derive(Debug, Clone, PartialEq, Eq)] #[stable(since = "1.7.0", feature = "strip_prefix")] pub struct StripPrefixError(()); impl Path { // The following (private!) function allows construction of a path from a u8 // slice, which is only safe when it is known to follow the OsStr encoding. unsafe fn from_u8_slice(s: &[u8]) -> &Path { unsafe { Path::new(u8_slice_as_os_str(s)) } } // The following (private!) function reveals the byte encoding used for OsStr. fn as_u8_slice(&self) -> &[u8] { self.inner.bytes() } /// Directly wraps a string slice as a `Path` slice. /// /// This is a cost-free conversion. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// Path::new("foo.txt"); /// ``` /// /// You can create `Path`s from `String`s, or even other `Path`s: /// /// ``` /// use std::path::Path; /// /// let string = String::from("foo.txt"); /// let from_string = Path::new(&string); /// let from_path = Path::new(&from_string); /// assert_eq!(from_string, from_path); /// ``` #[stable(feature = "rust1", since = "1.0.0")] pub fn new + ?Sized>(s: &S) -> &Path { unsafe { &*(s.as_ref() as *const OsStr as *const Path) } } fn from_inner_mut(inner: &mut OsStr) -> &mut Path { // SAFETY: Path is just a wrapper around OsStr, // therefore converting &mut OsStr to &mut Path is safe. unsafe { &mut *(inner as *mut OsStr as *mut Path) } } /// Yields the underlying [`OsStr`] slice. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let os_str = Path::new("foo.txt").as_os_str(); /// assert_eq!(os_str, std::ffi::OsStr::new("foo.txt")); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[inline] pub fn as_os_str(&self) -> &OsStr { &self.inner } /// Yields a mutable reference to the underlying [`OsStr`] slice. /// /// # Examples /// /// ``` /// #![feature(path_as_mut_os_str)] /// use std::path::{Path, PathBuf}; /// /// let mut path = PathBuf::from("Foo.TXT"); /// /// assert_ne!(path, Path::new("foo.txt")); /// /// path.as_mut_os_str().make_ascii_lowercase(); /// assert_eq!(path, Path::new("foo.txt")); /// ``` #[unstable(feature = "path_as_mut_os_str", issue = "105021")] #[must_use] #[inline] pub fn as_mut_os_str(&mut self) -> &mut OsStr { &mut self.inner } /// Yields a [`&str`] slice if the `Path` is valid unicode. /// /// This conversion may entail doing a check for UTF-8 validity. /// Note that validation is performed because non-UTF-8 strings are /// perfectly valid for some OS. /// /// [`&str`]: str /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path = Path::new("foo.txt"); /// assert_eq!(path.to_str(), Some("foo.txt")); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub fn to_str(&self) -> Option<&str> { self.inner.to_str() } /// Converts a `Path` to a [`Cow`]. /// /// Any non-Unicode sequences are replaced with /// [`U+FFFD REPLACEMENT CHARACTER`][U+FFFD]. /// /// [U+FFFD]: super::char::REPLACEMENT_CHARACTER /// /// # Examples /// /// Calling `to_string_lossy` on a `Path` with valid unicode: /// /// ``` /// use std::path::Path; /// /// let path = Path::new("foo.txt"); /// assert_eq!(path.to_string_lossy(), "foo.txt"); /// ``` /// /// Had `path` contained invalid unicode, the `to_string_lossy` call might /// have returned `"fo�.txt"`. #[stable(feature = "rust1", since = "1.0.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub fn to_string_lossy(&self) -> Cow<'_, str> { self.inner.to_string_lossy() } /// Converts a `Path` to an owned [`PathBuf`]. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path_buf = Path::new("foo.txt").to_path_buf(); /// assert_eq!(path_buf, std::path::PathBuf::from("foo.txt")); /// ``` #[rustc_conversion_suggestion] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[stable(feature = "rust1", since = "1.0.0")] pub fn to_path_buf(&self) -> PathBuf { PathBuf::from(self.inner.to_os_string()) } /// Returns `true` if the `Path` is absolute, i.e., if it is independent of /// the current directory. /// /// * On Unix, a path is absolute if it starts with the root, so /// `is_absolute` and [`has_root`] are equivalent. /// /// * On Windows, a path is absolute if it has a prefix and starts with the /// root: `c:\windows` is absolute, while `c:temp` and `\temp` are not. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// assert!(!Path::new("foo.txt").is_absolute()); /// ``` /// /// [`has_root`]: Path::has_root #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[allow(deprecated)] pub fn is_absolute(&self) -> bool { if cfg!(target_os = "redox") { // FIXME: Allow Redox prefixes self.has_root() || has_redox_scheme(self.as_u8_slice()) } else { self.has_root() && (cfg!(any(unix, target_os = "wasi")) || self.prefix().is_some()) } } /// Returns `true` if the `Path` is relative, i.e., not absolute. /// /// See [`is_absolute`]'s documentation for more details. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// assert!(Path::new("foo.txt").is_relative()); /// ``` /// /// [`is_absolute`]: Path::is_absolute #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[inline] pub fn is_relative(&self) -> bool { !self.is_absolute() } fn prefix(&self) -> Option> { self.components().prefix } /// Returns `true` if the `Path` has a root. /// /// * On Unix, a path has a root if it begins with `/`. /// /// * On Windows, a path has a root if it: /// * has no prefix and begins with a separator, e.g., `\windows` /// * has a prefix followed by a separator, e.g., `c:\windows` but not `c:windows` /// * has any non-disk prefix, e.g., `\\server\share` /// /// # Examples /// /// ``` /// use std::path::Path; /// /// assert!(Path::new("/etc/passwd").has_root()); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[inline] pub fn has_root(&self) -> bool { self.components().has_root() } /// Returns the `Path` without its final component, if there is one. /// /// This means it returns `Some("")` for relative paths with one component. /// /// Returns [`None`] if the path terminates in a root or prefix, or if it's /// the empty string. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path = Path::new("/foo/bar"); /// let parent = path.parent().unwrap(); /// assert_eq!(parent, Path::new("/foo")); /// /// let grand_parent = parent.parent().unwrap(); /// assert_eq!(grand_parent, Path::new("/")); /// assert_eq!(grand_parent.parent(), None); /// /// let relative_path = Path::new("foo/bar"); /// let parent = relative_path.parent(); /// assert_eq!(parent, Some(Path::new("foo"))); /// let grand_parent = parent.and_then(Path::parent); /// assert_eq!(grand_parent, Some(Path::new(""))); /// let great_grand_parent = grand_parent.and_then(Path::parent); /// assert_eq!(great_grand_parent, None); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[doc(alias = "dirname")] #[must_use] pub fn parent(&self) -> Option<&Path> { let mut comps = self.components(); let comp = comps.next_back(); comp.and_then(|p| match p { Component::Normal(_) | Component::CurDir | Component::ParentDir => { Some(comps.as_path()) } _ => None, }) } /// Produces an iterator over `Path` and its ancestors. /// /// The iterator will yield the `Path` that is returned if the [`parent`] method is used zero /// or more times. That means, the iterator will yield `&self`, `&self.parent().unwrap()`, /// `&self.parent().unwrap().parent().unwrap()` and so on. If the [`parent`] method returns /// [`None`], the iterator will do likewise. The iterator will always yield at least one value, /// namely `&self`. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let mut ancestors = Path::new("/foo/bar").ancestors(); /// assert_eq!(ancestors.next(), Some(Path::new("/foo/bar"))); /// assert_eq!(ancestors.next(), Some(Path::new("/foo"))); /// assert_eq!(ancestors.next(), Some(Path::new("/"))); /// assert_eq!(ancestors.next(), None); /// /// let mut ancestors = Path::new("../foo/bar").ancestors(); /// assert_eq!(ancestors.next(), Some(Path::new("../foo/bar"))); /// assert_eq!(ancestors.next(), Some(Path::new("../foo"))); /// assert_eq!(ancestors.next(), Some(Path::new(".."))); /// assert_eq!(ancestors.next(), Some(Path::new(""))); /// assert_eq!(ancestors.next(), None); /// ``` /// /// [`parent`]: Path::parent #[stable(feature = "path_ancestors", since = "1.28.0")] #[inline] pub fn ancestors(&self) -> Ancestors<'_> { Ancestors { next: Some(&self) } } /// Returns the final component of the `Path`, if there is one. /// /// If the path is a normal file, this is the file name. If it's the path of a directory, this /// is the directory name. /// /// Returns [`None`] if the path terminates in `..`. /// /// # Examples /// /// ``` /// use std::path::Path; /// use std::ffi::OsStr; /// /// assert_eq!(Some(OsStr::new("bin")), Path::new("/usr/bin/").file_name()); /// assert_eq!(Some(OsStr::new("foo.txt")), Path::new("tmp/foo.txt").file_name()); /// assert_eq!(Some(OsStr::new("foo.txt")), Path::new("foo.txt/.").file_name()); /// assert_eq!(Some(OsStr::new("foo.txt")), Path::new("foo.txt/.//").file_name()); /// assert_eq!(None, Path::new("foo.txt/..").file_name()); /// assert_eq!(None, Path::new("/").file_name()); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[doc(alias = "basename")] #[must_use] pub fn file_name(&self) -> Option<&OsStr> { self.components().next_back().and_then(|p| match p { Component::Normal(p) => Some(p), _ => None, }) } /// Returns a path that, when joined onto `base`, yields `self`. /// /// # Errors /// /// If `base` is not a prefix of `self` (i.e., [`starts_with`] /// returns `false`), returns [`Err`]. /// /// [`starts_with`]: Path::starts_with /// /// # Examples /// /// ``` /// use std::path::{Path, PathBuf}; /// /// let path = Path::new("/test/haha/foo.txt"); /// /// assert_eq!(path.strip_prefix("/"), Ok(Path::new("test/haha/foo.txt"))); /// assert_eq!(path.strip_prefix("/test"), Ok(Path::new("haha/foo.txt"))); /// assert_eq!(path.strip_prefix("/test/"), Ok(Path::new("haha/foo.txt"))); /// assert_eq!(path.strip_prefix("/test/haha/foo.txt"), Ok(Path::new(""))); /// assert_eq!(path.strip_prefix("/test/haha/foo.txt/"), Ok(Path::new(""))); /// /// assert!(path.strip_prefix("test").is_err()); /// assert!(path.strip_prefix("/haha").is_err()); /// /// let prefix = PathBuf::from("/test/"); /// assert_eq!(path.strip_prefix(prefix), Ok(Path::new("haha/foo.txt"))); /// ``` #[stable(since = "1.7.0", feature = "path_strip_prefix")] pub fn strip_prefix

(&self, base: P) -> Result<&Path, StripPrefixError> where P: AsRef, { self._strip_prefix(base.as_ref()) } fn _strip_prefix(&self, base: &Path) -> Result<&Path, StripPrefixError> { iter_after(self.components(), base.components()) .map(|c| c.as_path()) .ok_or(StripPrefixError(())) } /// Determines whether `base` is a prefix of `self`. /// /// Only considers whole path components to match. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path = Path::new("/etc/passwd"); /// /// assert!(path.starts_with("/etc")); /// assert!(path.starts_with("/etc/")); /// assert!(path.starts_with("/etc/passwd")); /// assert!(path.starts_with("/etc/passwd/")); // extra slash is okay /// assert!(path.starts_with("/etc/passwd///")); // multiple extra slashes are okay /// /// assert!(!path.starts_with("/e")); /// assert!(!path.starts_with("/etc/passwd.txt")); /// /// assert!(!Path::new("/etc/foo.rs").starts_with("/etc/foo")); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] pub fn starts_with>(&self, base: P) -> bool { self._starts_with(base.as_ref()) } fn _starts_with(&self, base: &Path) -> bool { iter_after(self.components(), base.components()).is_some() } /// Determines whether `child` is a suffix of `self`. /// /// Only considers whole path components to match. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path = Path::new("/etc/resolv.conf"); /// /// assert!(path.ends_with("resolv.conf")); /// assert!(path.ends_with("etc/resolv.conf")); /// assert!(path.ends_with("/etc/resolv.conf")); /// /// assert!(!path.ends_with("/resolv.conf")); /// assert!(!path.ends_with("conf")); // use .extension() instead /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] pub fn ends_with>(&self, child: P) -> bool { self._ends_with(child.as_ref()) } fn _ends_with(&self, child: &Path) -> bool { iter_after(self.components().rev(), child.components().rev()).is_some() } /// Extracts the stem (non-extension) portion of [`self.file_name`]. /// /// [`self.file_name`]: Path::file_name /// /// The stem is: /// /// * [`None`], if there is no file name; /// * The entire file name if there is no embedded `.`; /// * The entire file name if the file name begins with `.` and has no other `.`s within; /// * Otherwise, the portion of the file name before the final `.` /// /// # Examples /// /// ``` /// use std::path::Path; /// /// assert_eq!("foo", Path::new("foo.rs").file_stem().unwrap()); /// assert_eq!("foo.tar", Path::new("foo.tar.gz").file_stem().unwrap()); /// ``` /// /// # See Also /// This method is similar to [`Path::file_prefix`], which extracts the portion of the file name /// before the *first* `.` /// /// [`Path::file_prefix`]: Path::file_prefix /// #[stable(feature = "rust1", since = "1.0.0")] #[must_use] pub fn file_stem(&self) -> Option<&OsStr> { self.file_name().map(rsplit_file_at_dot).and_then(|(before, after)| before.or(after)) } /// Extracts the prefix of [`self.file_name`]. /// /// The prefix is: /// /// * [`None`], if there is no file name; /// * The entire file name if there is no embedded `.`; /// * The portion of the file name before the first non-beginning `.`; /// * The entire file name if the file name begins with `.` and has no other `.`s within; /// * The portion of the file name before the second `.` if the file name begins with `.` /// /// [`self.file_name`]: Path::file_name /// /// # Examples /// /// ``` /// # #![feature(path_file_prefix)] /// use std::path::Path; /// /// assert_eq!("foo", Path::new("foo.rs").file_prefix().unwrap()); /// assert_eq!("foo", Path::new("foo.tar.gz").file_prefix().unwrap()); /// ``` /// /// # See Also /// This method is similar to [`Path::file_stem`], which extracts the portion of the file name /// before the *last* `.` /// /// [`Path::file_stem`]: Path::file_stem /// #[unstable(feature = "path_file_prefix", issue = "86319")] #[must_use] pub fn file_prefix(&self) -> Option<&OsStr> { self.file_name().map(split_file_at_dot).and_then(|(before, _after)| Some(before)) } /// Extracts the extension (without the leading dot) of [`self.file_name`], if possible. /// /// The extension is: /// /// * [`None`], if there is no file name; /// * [`None`], if there is no embedded `.`; /// * [`None`], if the file name begins with `.` and has no other `.`s within; /// * Otherwise, the portion of the file name after the final `.` /// /// [`self.file_name`]: Path::file_name /// /// # Examples /// /// ``` /// use std::path::Path; /// /// assert_eq!("rs", Path::new("foo.rs").extension().unwrap()); /// assert_eq!("gz", Path::new("foo.tar.gz").extension().unwrap()); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] pub fn extension(&self) -> Option<&OsStr> { self.file_name().map(rsplit_file_at_dot).and_then(|(before, after)| before.and(after)) } /// Creates an owned [`PathBuf`] with `path` adjoined to `self`. /// /// If `path` is absolute, it replaces the current path. /// /// See [`PathBuf::push`] for more details on what it means to adjoin a path. /// /// # Examples /// /// ``` /// use std::path::{Path, PathBuf}; /// /// assert_eq!(Path::new("/etc").join("passwd"), PathBuf::from("/etc/passwd")); /// assert_eq!(Path::new("/etc").join("/bin/sh"), PathBuf::from("/bin/sh")); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] pub fn join>(&self, path: P) -> PathBuf { self._join(path.as_ref()) } fn _join(&self, path: &Path) -> PathBuf { let mut buf = self.to_path_buf(); buf.push(path); buf } /// Creates an owned [`PathBuf`] like `self` but with the given file name. /// /// See [`PathBuf::set_file_name`] for more details. /// /// # Examples /// /// ``` /// use std::path::{Path, PathBuf}; /// /// let path = Path::new("/tmp/foo.txt"); /// assert_eq!(path.with_file_name("bar.txt"), PathBuf::from("/tmp/bar.txt")); /// /// let path = Path::new("/tmp"); /// assert_eq!(path.with_file_name("var"), PathBuf::from("/var")); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use] pub fn with_file_name>(&self, file_name: S) -> PathBuf { self._with_file_name(file_name.as_ref()) } fn _with_file_name(&self, file_name: &OsStr) -> PathBuf { let mut buf = self.to_path_buf(); buf.set_file_name(file_name); buf } /// Creates an owned [`PathBuf`] like `self` but with the given extension. /// /// See [`PathBuf::set_extension`] for more details. /// /// # Examples /// /// ``` /// use std::path::{Path, PathBuf}; /// /// let path = Path::new("foo.rs"); /// assert_eq!(path.with_extension("txt"), PathBuf::from("foo.txt")); /// /// let path = Path::new("foo.tar.gz"); /// assert_eq!(path.with_extension(""), PathBuf::from("foo.tar")); /// assert_eq!(path.with_extension("xz"), PathBuf::from("foo.tar.xz")); /// assert_eq!(path.with_extension("").with_extension("txt"), PathBuf::from("foo.txt")); /// ``` #[stable(feature = "rust1", since = "1.0.0")] pub fn with_extension>(&self, extension: S) -> PathBuf { self._with_extension(extension.as_ref()) } fn _with_extension(&self, extension: &OsStr) -> PathBuf { let mut buf = self.to_path_buf(); buf.set_extension(extension); buf } /// Produces an iterator over the [`Component`]s of the path. /// /// When parsing the path, there is a small amount of normalization: /// /// * Repeated separators are ignored, so `a/b` and `a//b` both have /// `a` and `b` as components. /// /// * Occurrences of `.` are normalized away, except if they are at the /// beginning of the path. For example, `a/./b`, `a/b/`, `a/b/.` and /// `a/b` all have `a` and `b` as components, but `./a/b` starts with /// an additional [`CurDir`] component. /// /// * A trailing slash is normalized away, `/a/b` and `/a/b/` are equivalent. /// /// Note that no other normalization takes place; in particular, `a/c` /// and `a/b/../c` are distinct, to account for the possibility that `b` /// is a symbolic link (so its parent isn't `a`). /// /// # Examples /// /// ``` /// use std::path::{Path, Component}; /// use std::ffi::OsStr; /// /// let mut components = Path::new("/tmp/foo.txt").components(); /// /// assert_eq!(components.next(), Some(Component::RootDir)); /// assert_eq!(components.next(), Some(Component::Normal(OsStr::new("tmp")))); /// assert_eq!(components.next(), Some(Component::Normal(OsStr::new("foo.txt")))); /// assert_eq!(components.next(), None) /// ``` /// /// [`CurDir`]: Component::CurDir #[stable(feature = "rust1", since = "1.0.0")] pub fn components(&self) -> Components<'_> { let prefix = parse_prefix(self.as_os_str()); Components { path: self.as_u8_slice(), prefix, has_physical_root: has_physical_root(self.as_u8_slice(), prefix) || has_redox_scheme(self.as_u8_slice()), front: State::Prefix, back: State::Body, } } /// Produces an iterator over the path's components viewed as [`OsStr`] /// slices. /// /// For more information about the particulars of how the path is separated /// into components, see [`components`]. /// /// [`components`]: Path::components /// /// # Examples /// /// ``` /// use std::path::{self, Path}; /// use std::ffi::OsStr; /// /// let mut it = Path::new("/tmp/foo.txt").iter(); /// assert_eq!(it.next(), Some(OsStr::new(&path::MAIN_SEPARATOR.to_string()))); /// assert_eq!(it.next(), Some(OsStr::new("tmp"))); /// assert_eq!(it.next(), Some(OsStr::new("foo.txt"))); /// assert_eq!(it.next(), None) /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[inline] pub fn iter(&self) -> Iter<'_> { Iter { inner: self.components() } } /// Returns an object that implements [`Display`] for safely printing paths /// that may contain non-Unicode data. This may perform lossy conversion, /// depending on the platform. If you would like an implementation which /// escapes the path please use [`Debug`] instead. /// /// [`Display`]: fmt::Display /// [`Debug`]: fmt::Debug /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path = Path::new("/tmp/foo.rs"); /// /// println!("{}", path.display()); /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[must_use = "this does not display the path, \ it returns an object that can be displayed"] #[inline] pub fn display(&self) -> Display<'_> { Display { path: self } } /// Queries the file system to get information about a file, directory, etc. /// /// This function will traverse symbolic links to query information about the /// destination file. /// /// This is an alias to [`fs::metadata`]. /// /// # Examples /// /// ```no_run /// use std::path::Path; /// /// let path = Path::new("/Minas/tirith"); /// let metadata = path.metadata().expect("metadata call failed"); /// println!("{:?}", metadata.file_type()); /// ``` #[stable(feature = "path_ext", since = "1.5.0")] #[inline] pub fn metadata(&self) -> io::Result { fs::metadata(self) } /// Queries the metadata about a file without following symlinks. /// /// This is an alias to [`fs::symlink_metadata`]. /// /// # Examples /// /// ```no_run /// use std::path::Path; /// /// let path = Path::new("/Minas/tirith"); /// let metadata = path.symlink_metadata().expect("symlink_metadata call failed"); /// println!("{:?}", metadata.file_type()); /// ``` #[stable(feature = "path_ext", since = "1.5.0")] #[inline] pub fn symlink_metadata(&self) -> io::Result { fs::symlink_metadata(self) } /// Returns the canonical, absolute form of the path with all intermediate /// components normalized and symbolic links resolved. /// /// This is an alias to [`fs::canonicalize`]. /// /// # Examples /// /// ```no_run /// use std::path::{Path, PathBuf}; /// /// let path = Path::new("/foo/test/../test/bar.rs"); /// assert_eq!(path.canonicalize().unwrap(), PathBuf::from("/foo/test/bar.rs")); /// ``` #[stable(feature = "path_ext", since = "1.5.0")] #[inline] pub fn canonicalize(&self) -> io::Result { fs::canonicalize(self) } /// Reads a symbolic link, returning the file that the link points to. /// /// This is an alias to [`fs::read_link`]. /// /// # Examples /// /// ```no_run /// use std::path::Path; /// /// let path = Path::new("/laputa/sky_castle.rs"); /// let path_link = path.read_link().expect("read_link call failed"); /// ``` #[stable(feature = "path_ext", since = "1.5.0")] #[inline] pub fn read_link(&self) -> io::Result { fs::read_link(self) } /// Returns an iterator over the entries within a directory. /// /// The iterator will yield instances of [io::Result]<[fs::DirEntry]>. New /// errors may be encountered after an iterator is initially constructed. /// /// This is an alias to [`fs::read_dir`]. /// /// # Examples /// /// ```no_run /// use std::path::Path; /// /// let path = Path::new("/laputa"); /// for entry in path.read_dir().expect("read_dir call failed") { /// if let Ok(entry) = entry { /// println!("{:?}", entry.path()); /// } /// } /// ``` #[stable(feature = "path_ext", since = "1.5.0")] #[inline] pub fn read_dir(&self) -> io::Result { fs::read_dir(self) } /// Returns `true` if the path points at an existing entity. /// /// Warning: this method may be error-prone, consider using [`try_exists()`] instead! /// It also has a risk of introducing time-of-check to time-of-use (TOCTOU) bugs. /// /// This function will traverse symbolic links to query information about the /// destination file. /// /// If you cannot access the metadata of the file, e.g. because of a /// permission error or broken symbolic links, this will return `false`. /// /// # Examples /// /// ```no_run /// use std::path::Path; /// assert!(!Path::new("does_not_exist.txt").exists()); /// ``` /// /// # See Also /// /// This is a convenience function that coerces errors to false. If you want to /// check errors, call [`Path::try_exists`]. /// /// [`try_exists()`]: Self::try_exists #[stable(feature = "path_ext", since = "1.5.0")] #[must_use] #[inline] pub fn exists(&self) -> bool { fs::metadata(self).is_ok() } /// Returns `Ok(true)` if the path points at an existing entity. /// /// This function will traverse symbolic links to query information about the /// destination file. In case of broken symbolic links this will return `Ok(false)`. /// /// As opposed to the [`exists()`] method, this one doesn't silently ignore errors /// unrelated to the path not existing. (E.g. it will return `Err(_)` in case of permission /// denied on some of the parent directories.) /// /// Note that while this avoids some pitfalls of the `exists()` method, it still can not /// prevent time-of-check to time-of-use (TOCTOU) bugs. You should only use it in scenarios /// where those bugs are not an issue. /// /// # Examples /// /// ```no_run /// use std::path::Path; /// assert!(!Path::new("does_not_exist.txt").try_exists().expect("Can't check existence of file does_not_exist.txt")); /// assert!(Path::new("/root/secret_file.txt").try_exists().is_err()); /// ``` /// /// [`exists()`]: Self::exists #[stable(feature = "path_try_exists", since = "1.63.0")] #[inline] pub fn try_exists(&self) -> io::Result { fs::try_exists(self) } /// Returns `true` if the path exists on disk and is pointing at a regular file. /// /// This function will traverse symbolic links to query information about the /// destination file. /// /// If you cannot access the metadata of the file, e.g. because of a /// permission error or broken symbolic links, this will return `false`. /// /// # Examples /// /// ```no_run /// use std::path::Path; /// assert_eq!(Path::new("./is_a_directory/").is_file(), false); /// assert_eq!(Path::new("a_file.txt").is_file(), true); /// ``` /// /// # See Also /// /// This is a convenience function that coerces errors to false. If you want to /// check errors, call [`fs::metadata`] and handle its [`Result`]. Then call /// [`fs::Metadata::is_file`] if it was [`Ok`]. /// /// When the goal is simply to read from (or write to) the source, the most /// reliable way to test the source can be read (or written to) is to open /// it. Only using `is_file` can break workflows like `diff <( prog_a )` on /// a Unix-like system for example. See [`fs::File::open`] or /// [`fs::OpenOptions::open`] for more information. #[stable(feature = "path_ext", since = "1.5.0")] #[must_use] pub fn is_file(&self) -> bool { fs::metadata(self).map(|m| m.is_file()).unwrap_or(false) } /// Returns `true` if the path exists on disk and is pointing at a directory. /// /// This function will traverse symbolic links to query information about the /// destination file. /// /// If you cannot access the metadata of the file, e.g. because of a /// permission error or broken symbolic links, this will return `false`. /// /// # Examples /// /// ```no_run /// use std::path::Path; /// assert_eq!(Path::new("./is_a_directory/").is_dir(), true); /// assert_eq!(Path::new("a_file.txt").is_dir(), false); /// ``` /// /// # See Also /// /// This is a convenience function that coerces errors to false. If you want to /// check errors, call [`fs::metadata`] and handle its [`Result`]. Then call /// [`fs::Metadata::is_dir`] if it was [`Ok`]. #[stable(feature = "path_ext", since = "1.5.0")] #[must_use] pub fn is_dir(&self) -> bool { fs::metadata(self).map(|m| m.is_dir()).unwrap_or(false) } /// Returns `true` if the path exists on disk and is pointing at a symbolic link. /// /// This function will not traverse symbolic links. /// In case of a broken symbolic link this will also return true. /// /// If you cannot access the directory containing the file, e.g., because of a /// permission error, this will return false. /// /// # Examples /// #[cfg_attr(unix, doc = "```no_run")] #[cfg_attr(not(unix), doc = "```ignore")] /// use std::path::Path; /// use std::os::unix::fs::symlink; /// /// let link_path = Path::new("link"); /// symlink("/origin_does_not_exist/", link_path).unwrap(); /// assert_eq!(link_path.is_symlink(), true); /// assert_eq!(link_path.exists(), false); /// ``` /// /// # See Also /// /// This is a convenience function that coerces errors to false. If you want to /// check errors, call [`fs::symlink_metadata`] and handle its [`Result`]. Then call /// [`fs::Metadata::is_symlink`] if it was [`Ok`]. #[must_use] #[stable(feature = "is_symlink", since = "1.58.0")] pub fn is_symlink(&self) -> bool { fs::symlink_metadata(self).map(|m| m.is_symlink()).unwrap_or(false) } /// Converts a [`Box`](Box) into a [`PathBuf`] without copying or /// allocating. #[stable(feature = "into_boxed_path", since = "1.20.0")] #[must_use = "`self` will be dropped if the result is not used"] pub fn into_path_buf(self: Box) -> PathBuf { let rw = Box::into_raw(self) as *mut OsStr; let inner = unsafe { Box::from_raw(rw) }; PathBuf { inner: OsString::from(inner) } } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for Path { #[inline] fn as_ref(&self) -> &OsStr { &self.inner } } #[stable(feature = "rust1", since = "1.0.0")] impl fmt::Debug for Path { fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { fmt::Debug::fmt(&self.inner, formatter) } } /// Helper struct for safely printing paths with [`format!`] and `{}`. /// /// A [`Path`] might contain non-Unicode data. This `struct` implements the /// [`Display`] trait in a way that mitigates that. It is created by the /// [`display`](Path::display) method on [`Path`]. This may perform lossy /// conversion, depending on the platform. If you would like an implementation /// which escapes the path please use [`Debug`] instead. /// /// # Examples /// /// ``` /// use std::path::Path; /// /// let path = Path::new("/tmp/foo.rs"); /// /// println!("{}", path.display()); /// ``` /// /// [`Display`]: fmt::Display /// [`format!`]: crate::format #[stable(feature = "rust1", since = "1.0.0")] pub struct Display<'a> { path: &'a Path, } #[stable(feature = "rust1", since = "1.0.0")] impl fmt::Debug for Display<'_> { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { fmt::Debug::fmt(&self.path, f) } } #[stable(feature = "rust1", since = "1.0.0")] impl fmt::Display for Display<'_> { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { self.path.inner.display(f) } } #[stable(feature = "rust1", since = "1.0.0")] impl cmp::PartialEq for Path { #[inline] fn eq(&self, other: &Path) -> bool { self.components() == other.components() } } #[stable(feature = "rust1", since = "1.0.0")] impl Hash for Path { fn hash(&self, h: &mut H) { let bytes = self.as_u8_slice(); let (prefix_len, verbatim) = match parse_prefix(&self.inner) { Some(prefix) => { prefix.hash(h); (prefix.len(), prefix.is_verbatim()) } None => (0, false), }; let bytes = &bytes[prefix_len..]; let mut component_start = 0; let mut bytes_hashed = 0; for i in 0..bytes.len() { let is_sep = if verbatim { is_verbatim_sep(bytes[i]) } else { is_sep_byte(bytes[i]) }; if is_sep { if i > component_start { let to_hash = &bytes[component_start..i]; h.write(to_hash); bytes_hashed += to_hash.len(); } // skip over separator and optionally a following CurDir item // since components() would normalize these away. component_start = i + 1; let tail = &bytes[component_start..]; if !verbatim { component_start += match tail { [b'.'] => 1, [b'.', sep @ _, ..] if is_sep_byte(*sep) => 1, _ => 0, }; } } } if component_start < bytes.len() { let to_hash = &bytes[component_start..]; h.write(to_hash); bytes_hashed += to_hash.len(); } h.write_usize(bytes_hashed); } } #[stable(feature = "rust1", since = "1.0.0")] impl cmp::Eq for Path {} #[stable(feature = "rust1", since = "1.0.0")] impl cmp::PartialOrd for Path { #[inline] fn partial_cmp(&self, other: &Path) -> Option { Some(compare_components(self.components(), other.components())) } } #[stable(feature = "rust1", since = "1.0.0")] impl cmp::Ord for Path { #[inline] fn cmp(&self, other: &Path) -> cmp::Ordering { compare_components(self.components(), other.components()) } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for Path { #[inline] fn as_ref(&self) -> &Path { self } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for OsStr { #[inline] fn as_ref(&self) -> &Path { Path::new(self) } } #[stable(feature = "cow_os_str_as_ref_path", since = "1.8.0")] impl AsRef for Cow<'_, OsStr> { #[inline] fn as_ref(&self) -> &Path { Path::new(self) } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for OsString { #[inline] fn as_ref(&self) -> &Path { Path::new(self) } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for str { #[inline] fn as_ref(&self) -> &Path { Path::new(self) } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for String { #[inline] fn as_ref(&self) -> &Path { Path::new(self) } } #[stable(feature = "rust1", since = "1.0.0")] impl AsRef for PathBuf { #[inline] fn as_ref(&self) -> &Path { self } } #[stable(feature = "path_into_iter", since = "1.6.0")] impl<'a> IntoIterator for &'a PathBuf { type Item = &'a OsStr; type IntoIter = Iter<'a>; #[inline] fn into_iter(self) -> Iter<'a> { self.iter() } } #[stable(feature = "path_into_iter", since = "1.6.0")] impl<'a> IntoIterator for &'a Path { type Item = &'a OsStr; type IntoIter = Iter<'a>; #[inline] fn into_iter(self) -> Iter<'a> { self.iter() } } macro_rules! impl_cmp { (<$($life:lifetime),*> $lhs:ty, $rhs: ty) => { #[stable(feature = "partialeq_path", since = "1.6.0")] impl<$($life),*> PartialEq<$rhs> for $lhs { #[inline] fn eq(&self, other: &$rhs) -> bool { ::eq(self, other) } } #[stable(feature = "partialeq_path", since = "1.6.0")] impl<$($life),*> PartialEq<$lhs> for $rhs { #[inline] fn eq(&self, other: &$lhs) -> bool { ::eq(self, other) } } #[stable(feature = "cmp_path", since = "1.8.0")] impl<$($life),*> PartialOrd<$rhs> for $lhs { #[inline] fn partial_cmp(&self, other: &$rhs) -> Option { ::partial_cmp(self, other) } } #[stable(feature = "cmp_path", since = "1.8.0")] impl<$($life),*> PartialOrd<$lhs> for $rhs { #[inline] fn partial_cmp(&self, other: &$lhs) -> Option { ::partial_cmp(self, other) } } }; } impl_cmp!(<> PathBuf, Path); impl_cmp!(<'a> PathBuf, &'a Path); impl_cmp!(<'a> Cow<'a, Path>, Path); impl_cmp!(<'a, 'b> Cow<'a, Path>, &'b Path); impl_cmp!(<'a> Cow<'a, Path>, PathBuf); macro_rules! impl_cmp_os_str { (<$($life:lifetime),*> $lhs:ty, $rhs: ty) => { #[stable(feature = "cmp_path", since = "1.8.0")] impl<$($life),*> PartialEq<$rhs> for $lhs { #[inline] fn eq(&self, other: &$rhs) -> bool { ::eq(self, other.as_ref()) } } #[stable(feature = "cmp_path", since = "1.8.0")] impl<$($life),*> PartialEq<$lhs> for $rhs { #[inline] fn eq(&self, other: &$lhs) -> bool { ::eq(self.as_ref(), other) } } #[stable(feature = "cmp_path", since = "1.8.0")] impl<$($life),*> PartialOrd<$rhs> for $lhs { #[inline] fn partial_cmp(&self, other: &$rhs) -> Option { ::partial_cmp(self, other.as_ref()) } } #[stable(feature = "cmp_path", since = "1.8.0")] impl<$($life),*> PartialOrd<$lhs> for $rhs { #[inline] fn partial_cmp(&self, other: &$lhs) -> Option { ::partial_cmp(self.as_ref(), other) } } }; } impl_cmp_os_str!(<> PathBuf, OsStr); impl_cmp_os_str!(<'a> PathBuf, &'a OsStr); impl_cmp_os_str!(<'a> PathBuf, Cow<'a, OsStr>); impl_cmp_os_str!(<> PathBuf, OsString); impl_cmp_os_str!(<> Path, OsStr); impl_cmp_os_str!(<'a> Path, &'a OsStr); impl_cmp_os_str!(<'a> Path, Cow<'a, OsStr>); impl_cmp_os_str!(<> Path, OsString); impl_cmp_os_str!(<'a> &'a Path, OsStr); impl_cmp_os_str!(<'a, 'b> &'a Path, Cow<'b, OsStr>); impl_cmp_os_str!(<'a> &'a Path, OsString); impl_cmp_os_str!(<'a> Cow<'a, Path>, OsStr); impl_cmp_os_str!(<'a, 'b> Cow<'a, Path>, &'b OsStr); impl_cmp_os_str!(<'a> Cow<'a, Path>, OsString); #[stable(since = "1.7.0", feature = "strip_prefix")] impl fmt::Display for StripPrefixError { #[allow(deprecated, deprecated_in_future)] fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { self.description().fmt(f) } } #[stable(since = "1.7.0", feature = "strip_prefix")] impl Error for StripPrefixError { #[allow(deprecated)] fn description(&self) -> &str { "prefix not found" } } /// Makes the path absolute without accessing the filesystem. /// /// If the path is relative, the current directory is used as the base directory. /// All intermediate components will be resolved according to platforms-specific /// rules but unlike [`canonicalize`][crate::fs::canonicalize] this does not /// resolve symlinks and may succeed even if the path does not exist. /// /// If the `path` is empty or getting the /// [current directory][crate::env::current_dir] fails then an error will be /// returned. /// /// # Examples /// /// ## Posix paths /// /// ``` /// #![feature(absolute_path)] /// # #[cfg(unix)] /// fn main() -> std::io::Result<()> { /// use std::path::{self, Path}; /// /// // Relative to absolute /// let absolute = path::absolute("foo/./bar")?; /// assert!(absolute.ends_with("foo/bar")); /// /// // Absolute to absolute /// let absolute = path::absolute("/foo//test/.././bar.rs")?; /// assert_eq!(absolute, Path::new("/foo/test/../bar.rs")); /// Ok(()) /// } /// # #[cfg(not(unix))] /// # fn main() {} /// ``` /// /// The path is resolved using [POSIX semantics][posix-semantics] except that /// it stops short of resolving symlinks. This means it will keep `..` /// components and trailing slashes. /// /// ## Windows paths /// /// ``` /// #![feature(absolute_path)] /// # #[cfg(windows)] /// fn main() -> std::io::Result<()> { /// use std::path::{self, Path}; /// /// // Relative to absolute /// let absolute = path::absolute("foo/./bar")?; /// assert!(absolute.ends_with(r"foo\bar")); /// /// // Absolute to absolute /// let absolute = path::absolute(r"C:\foo//test\..\./bar.rs")?; /// /// assert_eq!(absolute, Path::new(r"C:\foo\bar.rs")); /// Ok(()) /// } /// # #[cfg(not(windows))] /// # fn main() {} /// ``` /// /// For verbatim paths this will simply return the path as given. For other /// paths this is currently equivalent to calling [`GetFullPathNameW`][windows-path] /// This may change in the future. /// /// [posix-semantics]: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap04.html#tag_04_13 /// [windows-path]: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getfullpathnamew #[unstable(feature = "absolute_path", issue = "92750")] pub fn absolute>(path: P) -> io::Result { let path = path.as_ref(); if path.as_os_str().is_empty() { Err(io::const_io_error!(io::ErrorKind::InvalidInput, "cannot make an empty path absolute",)) } else { sys::path::absolute(path) } }