Remove nohash-hasher dependency

Signed-off-by: Liam Gray <[email protected]>

Author: hoxxep

Cargo.toml

@@ -24,7 +24,6 @@ push = ["reqwest", "libc", "protobuf"]
 [dependencies]
 cfg-if = "^1.0"
 fnv = "^1.0"
-nohash-hasher = "0.2.0"
 lazy_static = "^1.4"
 libc = { version = "^0.2", optional = true }
 parking_lot = "^0.12"

src/lib.rs

@@ -158,6 +158,7 @@ mod errors;
 mod gauge;
 mod histogram;
 mod metrics;
+mod nohash;
 mod pulling_gauge;
 #[cfg(feature = "push")]
 mod push;

src/nohash.rs

@@ -0,0 +1,23 @@
+use std::hash::{BuildHasherDefault, Hasher};
+
+/// Inspired by nohash-hasher, but we avoid the crate dependency because it's in public archive.
+#[derive(Copy, Clone, Debug, Default)]
+pub struct NoHashHasher(u64);
+
+pub type BuildNoHashHasher = BuildHasherDefault<NoHashHasher>;
+
+impl Hasher for NoHashHasher {
+    #[inline]
+    fn finish(&self) -> u64 {
+        self.0
+    }
+
+    fn write(&mut self, _bytes: &[u8]) {
+        panic!("Invalid use of NoHashHasher");
+    }
+
+    #[inline]
+    fn write_u64(&mut self, i: u64) {
+        self.0 = i;
+    }
+}

src/vec.rs

@@ -5,12 +5,12 @@ use std::collections::HashMap;
 use std::hash::{BuildHasher, Hasher};
 use std::sync::Arc;
 use fnv::FnvHasher;
-use nohash_hasher::BuildNoHashHasher;
 use parking_lot::RwLock;
 
 use crate::desc::{Desc, Describer};
 use crate::errors::{Error, Result};
 use crate::metrics::{Collector, Metric};
+use crate::nohash::BuildNoHashHasher;
 use crate::proto::{MetricFamily, MetricType};
 
 /// An interface for building a metric vector.
@@ -27,7 +27,7 @@ pub trait MetricVecBuilder: Send + Sync + Clone {
 #[derive(Debug)]
 pub(crate) struct MetricVecCore<T: MetricVecBuilder> {
     // the key is pre-hashed, and so we use a no-hash hasher to avoid hashing again.
-    pub children: RwLock<HashMap<u64, T::M, BuildNoHashHasher<u64>>>,
+    pub children: RwLock<HashMap<u64, T::M, BuildNoHashHasher>>,
     pub desc: Desc,
     pub metric_type: MetricType,
     pub new_metric: T,