From b9e9b4a1461e3a49b68db56413324dc1b6a2ed60 Mon Sep 17 00:00:00 2001 From: Tobias Stolzmann Date: Wed, 28 Feb 2018 15:29:16 +0100 Subject: [PATCH] Add std::path::Path::ancestors Squashed commit of the following: commit 1b5d55e26f667b1a25c83c5db0cbb072013a5122 Author: Tobias Stolzmann Date: Wed Feb 28 00:06:15 2018 +0100 Bugfix commit 4265c2db0b0aaa66fdeace5d329665fd2d13903a Author: Tobias Stolzmann Date: Tue Feb 27 22:59:12 2018 +0100 Rename std::path::Path::parents into std::path::Path::ancestors commit 2548e4b14d377d20adad0f08304a0dd6f8e48e23 Author: Tobias Stolzmann Date: Tue Feb 27 12:50:37 2018 +0100 Add tracking issue commit 3e2ce51a6eea0e39af05849f76dd2cefd5035e86 Author: Tobias Stolzmann Date: Mon Feb 26 15:05:15 2018 +0100 impl FusedIterator for Parents commit a7e096420809740311e19d963d4aba6df77be2f9 Author: Tobias Stolzmann Date: Mon Feb 26 14:38:41 2018 +0100 Clarify that the iterator returned will yield at least one value commit 796a36ea203cd197cc4c810eebd21c7e3433e6f1 Author: Tobias Stolzmann Date: Thu Feb 22 14:01:21 2018 +0100 Fix examples commit e279383b21f11c97269cb355a5b2a0ecdb65bb0c Author: Tobias Stolzmann Date: Thu Feb 22 04:47:24 2018 +0100 Add std::path::Path::parents --- src/libstd/path.rs | 75 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 75 insertions(+) diff --git a/src/libstd/path.rs b/src/libstd/path.rs index 4bbad30a5a315..1608a752a463f 100644 --- a/src/libstd/path.rs +++ b/src/libstd/path.rs @@ -1035,6 +1035,50 @@ impl<'a> cmp::Ord for Components<'a> { } } +/// An iterator over [`Path`] and its ancestors. +/// +/// This `struct` is created by the [`ancestors`] method on [`Path`]. +/// See its documentation for more. +/// +/// # Examples +/// +/// ``` +/// #![feature(path_ancestors)] +/// +/// use std::path::Path; +/// +/// let path = Path::new("/foo/bar"); +/// +/// for ancestor in path.ancestors() { +/// println!("{}", ancestor.display()); +/// } +/// ``` +/// +/// [`ancestors`]: struct.Path.html#method.ancestors +/// [`Path`]: struct.Path.html +#[derive(Copy, Clone, Debug)] +#[unstable(feature = "path_ancestors", issue = "48581")] +pub struct Ancestors<'a> { + next: Option<&'a Path>, +} + +#[unstable(feature = "path_ancestors", issue = "48581")] +impl<'a> Iterator for Ancestors<'a> { + type Item = &'a Path; + + fn next(&mut self) -> Option { + let next = self.next; + self.next = match next { + Some(path) => path.parent(), + None => None, + }; + next + } +} + +#[unstable(feature = "fused", issue = "35602")] +impl<'a> FusedIterator for Ancestors<'a> {} + //////////////////////////////////////////////////////////////////////////////// // Basic types and traits //////////////////////////////////////////////////////////////////////////////// @@ -1820,6 +1864,37 @@ impl Path { }) } + /// 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 + /// + /// ``` + /// #![feature(path_ancestors)] + /// + /// 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); + /// ``` + /// + /// [`None`]: ../../std/option/enum.Option.html#variant.None + /// [`parent`]: struct.Path.html#method.parent + #[unstable(feature = "path_ancestors", issue = "48581")] + 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