Implement Hash trait for Bytes and String types

sway-lib-std/src/bytes.sw

@@ -537,60 +537,6 @@ impl Bytes {
     pub fn is_empty(self) -> bool {
         self.len == 0
     }
-
-    /// Returns the `SHA-2-256` hash of the elements.
-    ///
-    /// # Returns
-    ///
-    /// * [b256] - The `SHA-2-256` hash of the elements.
-    ///
-    /// # Examples
-    ///
-    /// ```sway
-    /// use std:bytes::Bytes;
-    ///
-    /// fn foo() {
-    ///     let bytes = Bytes::new();
-    ///     bytes.push(1);
-    ///     bytes.push(2);
-    ///     bytes.push(3);
-    ///     let sha256_hash = bytes.sha256();
-    /// }
-    /// ```
-    pub fn sha256(self) -> b256 {
-        let mut result_buffer = b256::min();
-        asm(hash: result_buffer, ptr: self.buf.ptr, bytes: self.len) {
-            s256 hash ptr bytes;
-            hash: b256
-        }
-    }
-
-    /// Returns the `KECCAK-256` hash of the elements.
-    ///
-    /// # Returns
-    ///
-    /// * [b256] - The `KECCAK-256` hash of the elements.
-    ///
-    /// # Examples
-    ///
-    /// ```sway
-    /// use std:bytes::Bytes;
-    ///
-    /// fn foo() {
-    ///     let bytes = Bytes::new();
-    ///     bytes.push(1);
-    ///     bytes.push(2);
-    ///     bytes.push(3);
-    ///     let keccak256_hash = bytes.keccak256();
-    /// }
-    /// ```
-    pub fn keccak256(self) -> b256 {
-        let mut result_buffer = b256::min();
-        asm(hash: result_buffer, ptr: self.buf.ptr, bytes: self.len) {
-            k256 hash ptr bytes;
-            hash: b256
-        }
-    }
 }
 
 // Need to use seperate impl blocks for now: https://github.com/FuelLabs/sway/issues/1548

sway-lib-std/src/hash.sw

@@ -18,11 +18,19 @@ impl Hasher {
     }
 
     pub fn sha256(self) -> b256 {
-        self.bytes.sha256()
+        let mut result_buffer = b256::min();
+        asm(hash: result_buffer, ptr: self.bytes.buf.ptr, bytes: self.bytes.len) {
+            s256 hash ptr bytes;
+            hash: b256
+        }
     }
 
     pub fn keccak256(self) -> b256 {
-        self.bytes.keccak256()
+        let mut result_buffer = b256::min();
+        asm(hash: result_buffer, ptr: self.bytes.buf.ptr, bytes: self.bytes.len) {
+            k256 hash ptr bytes;
+            hash: b256
+        }
     }
 }
 
@@ -123,6 +131,12 @@ impl Hash for bool {
     }
 }
 
+impl Hash for Bytes {
+    fn hash(self, ref mut state: Hasher) {
+        state.write(self);
+    }
+}
+
 impl<A, B> Hash for (A, B) where A: Hash, B: Hash  {
     #![inline(never)]
     fn hash(self, ref mut state: Hasher) {
@@ -418,4 +432,22 @@ fn test_hasher_sha256_bool() {
     true.hash(hasher);
     let sha256 = hasher.sha256();
     assert(sha256 == 0x4bf5122f344554c53bde2ebb8cd2b7e3d1600ad631c385a5d7cce23c7785459a);
-}
+}
+
+#[test]
+fn test_hasher_sha256_bytes() {
+    use ::assert::assert;
+    let mut hasher = Hasher::new();
+    let mut bytes = Bytes::new();
+    bytes.push(0u8);
+    bytes.hash(hasher);
+    let sha256 = hasher.sha256();
+    assert(sha256 == 0x6e340b9cffb37a989ca544e6bb780a2c78901d3fb33738768511a30617afa01d);
+
+    let mut hasher = Hasher::new();
+    let mut bytes = Bytes::new();
+    bytes.push(1u8);
+    bytes.hash(hasher);
+    let sha256 = hasher.sha256();
+    assert(sha256 == 0x4bf5122f344554c53bde2ebb8cd2b7e3d1600ad631c385a5d7cce23c7785459a);
+}

sway-lib-std/src/string.sw

@@ -1,9 +1,10 @@
 library;
 
+use ::assert::assert;
 use ::bytes::Bytes;
 use ::convert::From;
+use ::hash::{Hash, Hasher};
 use ::option::Option;
-use ::assert::assert;
 
 
 /// A UTF-8 encoded growable string.
@@ -265,6 +266,12 @@ impl Eq for String {
     }
 }
 
+impl Hash for String {
+    fn hash(self, ref mut state: Hasher) {
+        state.write(self.bytes);
+    }
+}
+
 // Tests
 
 #[test]
@@ -495,3 +502,15 @@ fn string_test_equal() {
     assert(string1 == string2);
     assert(string1 != string3);
 }
+
+#[test]
+fn string_test_hash() {
+    use ::hash::sha256;
+
+    let mut bytes = Bytes::new();
+    bytes.push(0u8);
+
+    let string = String::from(bytes);
+
+    assert(sha256(string) == sha256(bytes));
+}