Vendor dependenciesvendor

Just testing how CI works with this. I tend to prefer vendoring, as it
means that if you have a copy of the code *you can always build it*.
Even if you're 20 years in the future

This is the output of

```
cargo vendor --versioned-dirs
```

15 files changed, 4876 insertions, 0 deletions

diff --git a/vendor/hashlink-0.6.0/.cargo-checksum.json b/vendor/hashlink-0.6.0/.cargo-checksum.json
new file mode 100644
index 00000000..49b02702
--- /dev/null
+++ b/vendor/hashlink-0.6.0/.cargo-checksum.json
@@ -0,0 +1 @@
+{"files":{"CHANGELOG.md":"e9109ae14db72bf03cf72b5de1b2ecd421fac08c9185287ee80752c60b3ab7fe","Cargo.toml":"bd45b0b99fddf93fe48bfe59e372d55e43c0528b25aac4710711be1d086645be","LICENSE-APACHE":"c144680885b29e4719e2a51f0aab5439a1e02d980692b5aaf086cae12727f28b","LICENSE-MIT":"e915669a595b11a200873df8286561881b0e04932f6412a585db6297ba0bc97c","README.md":"f2b040b9aa899d3bd9fbb6c2391054980b00e7f475b6066071c17dd59d614d1c","src/lib.rs":"12f7bf2e1bdc312fd9740b639983916a2e7a8582c588902af8c4ac71b9032fde","src/linked_hash_map.rs":"d80f3d692655d18eb2d8f65be5d4f000cc95219a44f9b8f2eac1746502401d63","src/linked_hash_set.rs":"d71243afc3932df593e8a031266e7b71358f9304ad38a2a9baab4fec91d762fd","src/lru_cache.rs":"d2322af90780a3ef192f25d213f5af38e1dc6492a323fb361757d53692058774","src/serde.rs":"cc6287e48d740671c16848c1cf206da32011daa04efdca79f528736b4d2cdf03","tests/linked_hash_map.rs":"576decc19ebdc54bfbf653c1bf395792d80f5f0fd1d1f1eb9fbf1d45b295389b","tests/linked_hash_set.rs":"91fb96a11d1935343208e258696354b1436d7e497d786ceb6c681d0039a499d1","tests/lru_cache.rs":"c0328001d53e2a0d1ef6fb36550e8cbb989ef1914cef3657f1832b280f4d4572","tests/serde.rs":"d4b9b38d9812f4926dd7effff43c0d51d27c07477f732e9a2feb18f796b39b22"},"package":"d99cf782f0dc4372d26846bec3de7804ceb5df083c2d4462c0b8d2330e894fa8"}
\ No newline at end of file
diff --git a/vendor/hashlink-0.6.0/CHANGELOG.md b/vendor/hashlink-0.6.0/CHANGELOG.md
new file mode 100644
index 00000000..12963eab
--- /dev/null
+++ b/vendor/hashlink-0.6.0/CHANGELOG.md
@@ -0,0 +1,51 @@
+## [0.6.0]
+- API incompatible change: depend on hashbrown 0.9, re-export renamed
+  hashbrown::TryReserveError type.
+- Add a `Debug` impl to `LruCache` (thanks @thomcc!)
+- Adjust trait bounds for `LinkedHashMap::retain`, `LinkedHashSet::default` to
+  be less strict (to match hashbrown)
+- Adjust trait bounds for all `Debug` impls to be less strict (to match
+  hashbrown).
+- Adjust trait bounds for all `IntoIterator` impls to be less strict (to match
+  hashbrown).
+- Adjust trait bounds for `LruCache::with_hasher`, `LruCache::capacity`,
+  `LruCache::len`, `LruCache::is_empty`, `LruCache::clear`, `LruCache::iter`,
+  `LruCache::iter_mut`, and `LruCache::drain` to be less strict
+- Add optional serde support for `LinkedHashMap` and `LinkedHashSet`.
+- Add `to_back` and `to_front` methods for LinkedHashSet to control entry order.
+
+## [0.5.1]
+- Add `LinkedHashMap::remove_entry` and `LruCache::remove_entry`
+- Add `LruCache::new_unbounded` constructor that sets capacity to usize::MAX
+- Add `LruCache::get` method to go with `LruCache::get_mut`
+- Add `LruCache::peek` and `LruCache::peek_mut` to access the cache without
+  moving the entry in the LRU list
+
+## [0.5.0]
+- API incompatible change: depend on hashbrown 0.7
+
+## [0.4.0]
+- API incompatible change: depend on hashbrown 0.6
+- Passes miri
+
+## [0.3.0]
+- Add some *minimal* documentation for methods that change the internal ordering.
+- Decide on a pattern for methods that change the internal ordering: the word
+  "insert" means that it will move an existing entry to the back.
+- Some methods have been renamed to conform to the above system.
+
+## [0.2.1]
+- Fix variance for LinkedHashMap (now covariant where appropriate)
+- Add Debug impls to many more associated types
+- Add LinkedHashSet
+- Add `LinkedHashMap::retain`
+
+## [0.2.0]
+- Move `linked_hash_map` into its own module
+- Add `LruCache` type ported from `lru-cache` crate into its own module
+- Add `LruCache` entry and raw-entry API
+- Add `linked_hash_map` `IntoIter` iterator that is different from `Drain` iterator
+- Make `Drain` iterator recycle freed linked list nodes
+
+## [0.1.0]
+- Initial release
diff --git a/vendor/hashlink-0.6.0/Cargo.toml b/vendor/hashlink-0.6.0/Cargo.toml
new file mode 100644
index 00000000..6a5a2d41
--- /dev/null
+++ b/vendor/hashlink-0.6.0/Cargo.toml
@@ -0,0 +1,37 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies
+#
+# If you believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+edition = "2018"
+name = "hashlink"
+version = "0.6.0"
+authors = ["kyren <kerriganw@gmail.com>"]
+description = "HashMap-like containers that hold their key-value pairs in a user controllable order"
+documentation = "https://docs.rs/hashlink"
+readme = "README.md"
+keywords = ["data-structures"]
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/kyren/hashlink"
+[dependencies.hashbrown]
+version = "0.9.0"
+
+[dependencies.serde]
+version = "1.0"
+optional = true
+[dev-dependencies.serde_test]
+version = "1.0"
+
+[features]
+serde_impl = ["serde"]
+[badges.circle-ci]
+branch = "master"
+repository = "kyren/hashlink"
diff --git a/vendor/hashlink-0.6.0/LICENSE-APACHE b/vendor/hashlink-0.6.0/LICENSE-APACHE
new file mode 100644
index 00000000..1b22bef9
--- /dev/null
+++ b/vendor/hashlink-0.6.0/LICENSE-APACHE
@@ -0,0 +1,201 @@
+                              Apache License
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+Unless required by applicable law or agreed to in writing, software
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\ No newline at end of file
diff --git a/vendor/hashlink-0.6.0/LICENSE-MIT b/vendor/hashlink-0.6.0/LICENSE-MIT
new file mode 100644
index 00000000..b3cad876
--- /dev/null
+++ b/vendor/hashlink-0.6.0/LICENSE-MIT
@@ -0,0 +1,26 @@
+This work is derived in part from the `linked-hash-map` crate, Copyright (c)
+2015 The Rust Project Developers
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
\ No newline at end of file
diff --git a/vendor/hashlink-0.6.0/README.md b/vendor/hashlink-0.6.0/README.md
new file mode 100644
index 00000000..9272b0d4
--- /dev/null
+++ b/vendor/hashlink-0.6.0/README.md
@@ -0,0 +1,67 @@
+# hashlink -- HashMap-like containers that hold their key-value pairs in a user controllable order
+
+[![Build Status](https://img.shields.io/circleci/project/github/kyren/hashlink.svg)](https://circleci.com/gh/kyren/hashlink)
+[![Latest Version](https://img.shields.io/crates/v/hashlink.svg)](https://crates.io/crates/hashlink)
+[![API Documentation](https://docs.rs/hashlink/badge.svg)](https://docs.rs/hashlink)
+
+This crate is a fork of 
+[linked-hash-map](https://github.com/contain-rs/linked-hash-map) that builds on
+top of [hashbrown](https://github.com/rust-lang/hashbrown) to implement more up
+to date versions of `LinkedHashMap` `LinkedHashSet`, and `LruCache`.
+
+One important API change is that when a `LinkedHashMap` is used as a LRU cache,
+it allows you to easily retrieve an entry and move it to the back OR produce a
+new entry at the back without needlessly repeating key hashing and lookups:
+
+``` rust
+let mut lru_cache = LinkedHashMap::new();
+let key = "key".to_owned();
+// Try to find my expensive to construct and hash key
+let _cached_val = match lru_cache.raw_entry_mut().from_key(&key) {
+    RawEntryMut::Occupied(mut occupied) => {
+        // Cache hit, move entry to the back.
+        occupied.to_back();
+        occupied.into_mut()
+    }
+    RawEntryMut::Vacant(vacant) => {
+        // Insert expensive to construct key and expensive to compute value,
+        // automatically inserted at the back.
+        vacant.insert(key.clone(), 42).1
+    }
+};
+```
+
+Or, a simpler way to do the same thing:
+
+``` rust
+let mut lru_cache = LinkedHashMap::new();
+let key = "key".to_owned();
+let _cached_val = lru_cache
+    .raw_entry_mut()
+    .from_key(&key)
+    .or_insert_with(|| (key.clone(), 42));
+```
+
+This crate contains a decent amount of unsafe code from handling its internal
+linked list, and the unsafe code has diverged quite a lot from the original
+`linked-hash-map` implementation.  It currently passes tests under miri and
+sanitizers, but it should probably still receive more review and testing, and
+check for test code coverage.
+
+## Credit
+
+There is a huge amount of code in this crate that is copied verbatim from
+`linked-hash-map` and `hashbrown`, especially tests, associated types like
+iterators, and things like `Debug` impls.
+
+## License
+
+This library is licensed the same as
+[linked-hash-map](https://github.com/contain-rs/linked-hash-map) and
+[hashbrown](https://github.com/rust-lang/hashbrown), it is licensed under either
+of:
+
+* MIT license [LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT
+* Apache License 2.0 [LICENSE-APACHE](LICENSE-APACHE) or https://opensource.org/licenses/Apache-2.0
+
+at your option.
diff --git a/vendor/hashlink-0.6.0/src/lib.rs b/vendor/hashlink-0.6.0/src/lib.rs
new file mode 100644
index 00000000..55bdcd2e
--- /dev/null
+++ b/vendor/hashlink-0.6.0/src/lib.rs
@@ -0,0 +1,9 @@
+pub mod linked_hash_map;
+pub mod linked_hash_set;
+pub mod lru_cache;
+#[cfg(feature = "serde_impl")]
+pub mod serde;
+
+pub use linked_hash_map::LinkedHashMap;
+pub use linked_hash_set::LinkedHashSet;
+pub use lru_cache::LruCache;
diff --git a/vendor/hashlink-0.6.0/src/linked_hash_map.rs b/vendor/hashlink-0.6.0/src/linked_hash_map.rs
new file mode 100644
index 00000000..32733ea2
--- /dev/null
+++ b/vendor/hashlink-0.6.0/src/linked_hash_map.rs
@@ -0,0 +1,2053 @@
+use std::{
+    borrow::Borrow,
+    cmp::Ordering,
+    fmt,
+    hash::{BuildHasher, Hash, Hasher},
+    iter::FromIterator,
+    marker::PhantomData,
+    mem::{self, MaybeUninit},
+    ops::{Index, IndexMut},
+    ptr::{self, NonNull},
+};
+
+use hashbrown::{hash_map, HashMap};
+
+pub type TryReserveError = hashbrown::TryReserveError;
+
+/// A version of `HashMap` that has a user controllable order for its entries.
+///
+/// It achieves this by keeping its entries in an internal linked list and using a `HashMap` to
+/// point at nodes in this linked list.
+///
+/// The order of entries defaults to "insertion order", but the user can also modify the order of
+/// existing entries by manually moving them to the front or back.
+///
+/// There are two kinds of methods that modify the order of the internal list:
+///
+/// * Methods that have names like `to_front` and `to_back` will unsurprisingly move an existing
+///   entry to the front or back
+/// * Methods that have the word `insert` will insert a new entry ot the back of the list, and if
+///   that method might replace an entry, that method will *also move that existing entry to the
+///   back*.
+pub struct LinkedHashMap<K, V, S = hash_map::DefaultHashBuilder> {
+    map: HashMap<NonNull<Node<K, V>>, (), NullHasher>,
+    // We need to keep any custom hash builder outside of the HashMap so we can access it alongside
+    // the entry API without mutable aliasing.
+    hash_builder: S,
+    // Circular linked list of nodes.  If `values` is non-null, it will point to a "guard node"
+    // which will never have an initialized key or value, `values.prev` will contain the last key /
+    // value in the list, `values.next` will contain the first key / value in the list.
+    values: Option<NonNull<Node<K, V>>>,
+    // *Singly* linked list of free nodes.  The `prev` pointers in the free list should be assumed
+    // invalid.
+    free: Option<NonNull<Node<K, V>>>,
+}
+
+impl<K, V> LinkedHashMap<K, V> {
+    #[inline]
+    pub fn new() -> Self {
+        Self {
+            hash_builder: hash_map::DefaultHashBuilder::default(),
+            map: HashMap::with_hasher(NullHasher),
+            values: None,
+            free: None,
+        }
+    }
+
+    #[inline]
+    pub fn with_capacity(capacity: usize) -> Self {
+        Self {
+            hash_builder: hash_map::DefaultHashBuilder::default(),
+            map: HashMap::with_capacity_and_hasher(capacity, NullHasher),
+            values: None,
+            free: None,
+        }
+    }
+}
+
+impl<K, V, S> LinkedHashMap<K, V, S> {
+    #[inline]
+    pub fn with_hasher(hash_builder: S) -> Self {
+        Self {
+            hash_builder,
+            map: HashMap::with_hasher(NullHasher),
+            values: None,
+            free: None,
+        }
+    }
+
+    #[inline]
+    pub fn with_capacity_and_hasher(capacity: usize, hash_builder: S) -> Self {
+        Self {
+            hash_builder,
+            map: HashMap::with_capacity_and_hasher(capacity, NullHasher),
+            values: None,
+            free: None,
+        }
+    }
+
+    #[inline]
+    pub fn reserve(&mut self, additional: usize) {
+        self.map.reserve(additional);
+    }
+
+    #[inline]
+    pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> {
+        self.map.try_reserve(additional)
+    }
+
+    #[inline]
+    pub fn shrink_to_fit(&mut self) {
+        self.map.shrink_to_fit();
+        unsafe { drop_free_nodes(self.free) };
+        self.free = None;
+    }
+
+    #[inline]
+    pub fn len(&self) -> usize {
+        self.map.len()
+    }
+
+    #[inline]
+    pub fn is_empty(&self) -> bool {
+        self.len() == 0
+    }
+
+    #[inline]
+    pub fn clear(&mut self) {
+        self.map.clear();
+        if let Some(mut values) = self.values {
+            unsafe {
+                drop_value_nodes(values);
+                values.as_mut().links.value = ValueLinks {
+                    prev: values,
+                    next: values,
+                };
+            }
+        }
+    }
+
+    #[inline]
+    pub fn iter(&self) -> Iter<K, V> {
+        let (head, tail) = if let Some(values) = self.values {
+            unsafe {
+                let ValueLinks { next, prev } = values.as_ref().links.value;
+                (next.as_ptr(), prev.as_ptr())
+            }
+        } else {
+            (ptr::null_mut(), ptr::null_mut())
+        };
+
+        Iter {
+            head,
+            tail,
+            remaining: self.len(),
+            marker: PhantomData,
+        }
+    }
+
+    #[inline]
+    pub fn iter_mut(&mut self) -> IterMut<K, V> {
+        let (head, tail) = if let Some(values) = self.values {
+            unsafe {
+                let ValueLinks { next, prev } = values.as_ref().links.value;
+                (Some(next), Some(prev))
+            }
+        } else {
+            (None, None)
+        };
+
+        IterMut {
+            head,
+            tail,
+            remaining: self.len(),
+            marker: PhantomData,
+        }
+    }
+
+    #[inline]
+    pub fn drain(&mut self) -> Drain<'_, K, V> {
+        unsafe {
+            let (head, tail) = if let Some(mut values) = self.values {
+                let ValueLinks { next, prev } = values.as_ref().links.value;
+                values.as_mut().links.value = ValueLinks {
+                    next: values,
+                    prev: values,
+                };
+                (Some(next), Some(prev))
+            } else {
+                (None, None)
+            };
+            let len = self.len();
+
+            self.map.clear();
+
+            Drain {
+                free: (&mut self.free).into(),
+                head,
+                tail,
+                remaining: len,
+                marker: PhantomData,
+            }
+        }
+    }
+
+    #[inline]
+    pub fn keys(&self) -> Keys<K, V> {
+        Keys { inner: self.iter() }
+    }
+
+    #[inline]
+    pub fn values(&self) -> Values<K, V> {
+        Values { inner: self.iter() }
+    }
+
+    #[inline]
+    pub fn values_mut(&mut self) -> ValuesMut<K, V> {
+        ValuesMut {
+            inner: self.iter_mut(),
+        }
+    }
+
+    #[inline]
+    pub fn front(&self) -> Option<(&K, &V)> {
+        if self.is_empty() {
+            return None;
+        }
+        unsafe {
+            let front = (*self.values.as_ptr()).links.value.next.as_ptr();
+            let (key, value) = (*front).entry_ref();
+            Some((key, value))
+        }
+    }
+
+    #[inline]
+    pub fn back(&self) -> Option<(&K, &V)> {
+        if self.is_empty() {
+            return None;
+        }
+        unsafe {
+            let back = &*(*self.values.as_ptr()).links.value.prev.as_ptr();
+            let (key, value) = (*back).entry_ref();
+            Some((key, value))
+        }
+    }
+
+    #[inline]
+    pub fn retain<F>(&mut self, mut f: F)
+    where
+        F: FnMut(&K, &mut V) -> bool,
+    {
+        // We do not drop the key and value when a value is filtered from the map during the call to
+        // `retain`.  We need to be very careful not to have a live `HashMap` entry pointing to
+        // either a dangling `Node` or a `Node` with dropped keys / values.  Since the key and value
+        // types may panic on drop, they may short-circuit the entry in the map actually being
+        // removed.  Instead, we push the removed nodes onto the free list eagerly, then try and
+        // drop the keys and values for any newly freed nodes *after* `HashMap::retain` has
+        // completely finished.
+        struct DropFilteredValues<'a, K, V> {
+            free: &'a mut Option<NonNull<Node<K, V>>>,
+            cur_free: Option<NonNull<Node<K, V>>>,
+        }
+
+        impl<'a, K, V> DropFilteredValues<'a, K, V> {
+            #[inline]
+            fn drop_later(&mut self, node: NonNull<Node<K, V>>) {
+                unsafe {
+                    detach_node(node);
+                    push_free(&mut self.cur_free, node);
+                }
+            }
+        }
+
+        impl<'a, K, V> Drop for DropFilteredValues<'a, K, V> {
+            fn drop(&mut self) {
+                unsafe {
+                    let end_free = self.cur_free;
+                    while self.cur_free != *self.free {
+                        let cur_free = self.cur_free.as_ptr();
+                        (*cur_free).take_entry();
+                        self.cur_free = (*cur_free).links.free.next;
+                    }
+                    *self.free = end_free;
+                }
+            }
+        }
+
+        let free = self.free;
+        let mut drop_filtered_values = DropFilteredValues {
+            free: &mut self.free,
+            cur_free: free,
+        };
+
+        self.map.retain(|&node, _| unsafe {
+            let (k, v) = (*node.as_ptr()).entry_mut();
+            if f(k, v) {
+                true
+            } else {
+                drop_filtered_values.drop_later(node);
+                false
+            }
+        });
+    }
+
+    #[inline]
+    pub fn hasher(&self) -> &S {
+        &self.hash_builder
+    }
+
+    #[inline]
+    pub fn capacity(&self) -> usize {
+        self.map.capacity()
+    }
+}
+
+impl<K, V, S> LinkedHashMap<K, V, S>
+where
+    K: Eq + Hash,