Auto merge of #53085 - ljedrz:cleanup_syntax_structures, r=ljedrz

Move SmallVector and ThinVec out of libsyntax

- move `libsyntax::util::SmallVector` tests to `librustc_data_structures::small_vec`
- remove `libsyntax::util::SmallVector`
- move `libsyntax::util::thin_vec` to `librustc_data_structures::thin_vec`

Other than moving these data structures where they belong it allows modules using `SmallVector<T>` (`SmallVec<[T; 1]>`) to specify their own length (e.g. 8 or 32) independently from `libsyntax`.

3 files changed, 2 insertions, 143 deletions

diff --git a/src/libsyntax/util/move_map.rs b/src/libsyntax/util/move_map.rs
index 8cc37afa354..eb2c5a2458c 100644
--- a/src/libsyntax/util/move_map.rs
+++ b/src/libsyntax/util/move_map.rs
@@ -9,8 +9,7 @@
 // except according to those terms.
 
 use std::ptr;
-
-use util::small_vector::SmallVector;
+use OneVector;
 
 pub trait MoveMap<T>: Sized {
     fn move_map<F>(self, mut f: F) -> Self where F: FnMut(T) -> T {
@@ -78,7 +77,7 @@ impl<T> MoveMap<T> for ::ptr::P<[T]> {
     }
 }
 
-impl<T> MoveMap<T> for SmallVector<T> {
+impl<T> MoveMap<T> for OneVector<T> {
     fn move_flat_map<F, I>(mut self, mut f: F) -> Self
         where F: FnMut(T) -> I,
               I: IntoIterator<Item=T>
diff --git a/src/libsyntax/util/small_vector.rs b/src/libsyntax/util/small_vector.rs
deleted file mode 100644
index 31e675836fc..00000000000
--- a/src/libsyntax/util/small_vector.rs
+++ /dev/null
@@ -1,81 +0,0 @@
-// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-use rustc_data_structures::small_vec::SmallVec;
-
-pub type SmallVector<T> = SmallVec<[T; 1]>;
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_len() {
-        let v: SmallVector<isize> = SmallVector::new();
-        assert_eq!(0, v.len());
-
-        assert_eq!(1, SmallVector::one(1).len());
-        assert_eq!(5, SmallVector::many(vec![1, 2, 3, 4, 5]).len());
-    }
-
-    #[test]
-    fn test_push_get() {
-        let mut v = SmallVector::new();
-        v.push(1);
-        assert_eq!(1, v.len());
-        assert_eq!(1, v[0]);
-        v.push(2);
-        assert_eq!(2, v.len());
-        assert_eq!(2, v[1]);
-        v.push(3);
-        assert_eq!(3, v.len());
-        assert_eq!(3, v[2]);
-    }
-
-    #[test]
-    fn test_from_iter() {
-        let v: SmallVector<isize> = (vec![1, 2, 3]).into_iter().collect();
-        assert_eq!(3, v.len());
-        assert_eq!(1, v[0]);
-        assert_eq!(2, v[1]);
-        assert_eq!(3, v[2]);
-    }
-
-    #[test]
-    fn test_move_iter() {
-        let v = SmallVector::new();
-        let v: Vec<isize> = v.into_iter().collect();
-        assert_eq!(v, Vec::new());
-
-        let v = SmallVector::one(1);
-        assert_eq!(v.into_iter().collect::<Vec<_>>(), [1]);
-
-        let v = SmallVector::many(vec![1, 2, 3]);
-        assert_eq!(v.into_iter().collect::<Vec<_>>(), [1, 2, 3]);
-    }
-
-    #[test]
-    #[should_panic]
-    fn test_expect_one_zero() {
-        let _: isize = SmallVector::new().expect_one("");
-    }
-
-    #[test]
-    #[should_panic]
-    fn test_expect_one_many() {
-        SmallVector::many(vec![1, 2]).expect_one("");
-    }
-
-    #[test]
-    fn test_expect_one_one() {
-        assert_eq!(1, SmallVector::one(1).expect_one(""));
-        assert_eq!(1, SmallVector::many(vec![1]).expect_one(""));
-    }
-}
diff --git a/src/libsyntax/util/thin_vec.rs b/src/libsyntax/util/thin_vec.rs
deleted file mode 100644
index 546686b46b8..00000000000
--- a/src/libsyntax/util/thin_vec.rs
+++ /dev/null
@@ -1,59 +0,0 @@
-// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-/// A vector type optimized for cases where this size is usually 0 (c.f. `SmallVector`).
-/// The `Option<Box<..>>` wrapping allows us to represent a zero sized vector with `None`,
-/// which uses only a single (null) pointer.
-#[derive(Clone, PartialEq, Eq, RustcEncodable, RustcDecodable, Hash, Debug)]
-pub struct ThinVec<T>(Option<Box<Vec<T>>>);
-
-impl<T> ThinVec<T> {
-    pub fn new() -> Self {
-        ThinVec(None)
-    }
-}
-
-impl<T> From<Vec<T>> for ThinVec<T> {
-    fn from(vec: Vec<T>) -> Self {
-        if vec.is_empty() {
-            ThinVec(None)
-        } else {
-            ThinVec(Some(Box::new(vec)))
-        }
-    }
-}
-
-impl<T> Into<Vec<T>> for ThinVec<T> {
-    fn into(self) -> Vec<T> {
-        match self {
-            ThinVec(None) => Vec::new(),
-            ThinVec(Some(vec)) => *vec,
-        }
-    }
-}
-
-impl<T> ::std::ops::Deref for ThinVec<T> {
-    type Target = [T];
-    fn deref(&self) -> &[T] {
-        match *self {
-            ThinVec(None) => &[],
-            ThinVec(Some(ref vec)) => vec,
-        }
-    }
-}
-
-impl<T> Extend<T> for ThinVec<T> {
-    fn extend<I: IntoIterator<Item = T>>(&mut self, iter: I) {
-        match *self {
-            ThinVec(Some(ref mut vec)) => vec.extend(iter),
-            ThinVec(None) => *self = iter.into_iter().collect::<Vec<_>>().into(),
-        }
-    }
-}