Use rusts internal hash algorithm.

Author: windelbouwman

vm/src/obj/objbytes.rs

@@ -5,15 +5,18 @@ use super::super::pyobject::{
 use super::super::vm::VirtualMachine;
 use super::objint;
 use super::objtype;
+use num_bigint::ToBigInt;
 use num_traits::ToPrimitive;
 use std::cell::Ref;
+use std::hash::{Hash, Hasher};
 use std::ops::Deref;
 // Binary data support
 
 // Fill bytes class methods:
 pub fn init(context: &PyContext) {
     let ref bytes_type = context.bytes_type;
     bytes_type.set_attr("__eq__", context.new_rustfunc(bytes_eq));
+    bytes_type.set_attr("__hash__", context.new_rustfunc(bytes_hash));
     bytes_type.set_attr("__new__", context.new_rustfunc(bytes_new));
     bytes_type.set_attr("__repr__", context.new_rustfunc(bytes_repr));
 }
@@ -64,6 +67,15 @@ fn bytes_eq(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     Ok(vm.ctx.new_bool(result))
 }
 
+fn bytes_hash(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
+    arg_check!(vm, args, required = [(zelf, Some(vm.ctx.bytes_type()))]);
+    let data = get_value(zelf);
+    let mut hasher = std::collections::hash_map::DefaultHasher::new();
+    data.hash(&mut hasher);
+    let hash = hasher.finish();
+    Ok(vm.ctx.new_int(hash.to_bigint().unwrap()))
+}
+
 pub fn get_value<'a>(obj: &'a PyObjectRef) -> impl Deref<Target = Vec<u8>> + 'a {
     Ref::map(obj.borrow(), |py_obj| {
         if let PyObjectKind::Bytes { ref value } = py_obj.kind {

vm/src/obj/objint.rs

@@ -8,10 +8,10 @@ use super::objstr;
 use super::objtype;
 use num_bigint::{BigInt, ToBigInt};
 use num_traits::{Pow, Signed, ToPrimitive, Zero};
+use std::hash::{Hash, Hasher};
 
 // This proxy allows for easy switching between types.
-// TODO: maybe this is a good idea:
-// type IntType = BigInt;
+type IntType = BigInt;
 
 fn int_repr(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(vm, args, required = [(int, Some(vm.ctx.int_type()))]);
@@ -47,7 +47,7 @@ pub fn to_int(
     vm: &mut VirtualMachine,
     obj: &PyObjectRef,
     base: u32,
-) -> Result<BigInt, PyObjectRef> {
+) -> Result<IntType, PyObjectRef> {
     let val = if objtype::isinstance(obj, &vm.ctx.int_type()) {
         get_value(obj)
     } else if objtype::isinstance(obj, &vm.ctx.float_type()) {
@@ -75,7 +75,7 @@ pub fn to_int(
 }
 
 // Retrieve inner int value:
-pub fn get_value(obj: &PyObjectRef) -> BigInt {
+pub fn get_value(obj: &PyObjectRef) -> IntType {
     if let PyObjectKind::Integer { value } = &obj.borrow().kind {
         value.clone()
     } else {
@@ -171,9 +171,11 @@ fn int_ge(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
 
 fn int_hash(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(vm, args, required = [(zelf, Some(vm.ctx.int_type()))]);
-
-    // TODO: how to hash int?
-    Ok(zelf.clone())
+    let value = BigInt::from_pyobj(zelf);
+    let mut hasher = std::collections::hash_map::DefaultHasher::new();
+    value.hash(&mut hasher);
+    let hash = hasher.finish();
+    Ok(vm.ctx.new_int(hash.to_bigint().unwrap()))
 }
 
 fn int_abs(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {

vm/src/obj/objstr.rs

@@ -7,6 +7,7 @@ use super::objsequence::PySliceableSequence;
 use super::objtype;
 use num_bigint::ToBigInt;
 use num_traits::ToPrimitive;
+use std::hash::{Hash, Hasher};
 
 pub fn init(context: &PyContext) {
     let ref str_type = context.str_type;
@@ -15,6 +16,7 @@ pub fn init(context: &PyContext) {
     str_type.set_attr("__contains__", context.new_rustfunc(str_contains));
     str_type.set_attr("__getitem__", context.new_rustfunc(str_getitem));
     str_type.set_attr("__gt__", context.new_rustfunc(str_gt));
+    str_type.set_attr("__hash__", context.new_rustfunc(str_hash));
     str_type.set_attr("__len__", context.new_rustfunc(str_len));
     str_type.set_attr("__mul__", context.new_rustfunc(str_mul));
     str_type.set_attr("__new__", context.new_rustfunc(str_new));
@@ -124,6 +126,15 @@ fn str_add(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     }
 }
 
+fn str_hash(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
+    arg_check!(vm, args, required = [(zelf, Some(vm.ctx.str_type()))]);
+    let value = get_value(zelf);
+    let mut hasher = std::collections::hash_map::DefaultHasher::new();
+    value.hash(&mut hasher);
+    let hash = hasher.finish();
+    Ok(vm.ctx.new_int(hash.to_bigint().unwrap()))
+}
+
 fn str_len(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(vm, args, required = [(s, Some(vm.ctx.str_type()))]);
     let sv = get_value(s);

vm/src/obj/objtuple.rs

@@ -9,7 +9,7 @@ use super::objsequence::{get_elements, get_item, seq_equal};
 use super::objstr;
 use super::objtype;
 use num_bigint::ToBigInt;
-use num_traits::ToPrimitive;
+use std::hash::{Hash, Hasher};
 
 fn tuple_eq(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(
@@ -30,22 +30,14 @@ fn tuple_eq(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
 
 fn tuple_hash(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(vm, args, required = [(zelf, Some(vm.ctx.tuple_type()))]);
-
-    let mut x: usize = 0x345678;
     let elements = get_elements(zelf);
-    let len: usize = elements.len();
-    let mut mult = 0xf4243;
-
-    for elem in elements.iter() {
-        let y: usize = objint::get_value(&vm.call_method(elem, "__hash__", vec![])?)
-            .to_usize()
-            .unwrap();
-        x = (x ^ y) * mult;
-        mult = mult + 82520 + len * 2;
+    let mut hasher = std::collections::hash_map::DefaultHasher::new();
+    for element in elements.iter() {
+        let element_hash = objint::get_value(&vm.call_method(element, "__hash__", vec![])?);
+        element_hash.hash(&mut hasher);
     }
-    x += 97531;
-
-    Ok(vm.ctx.new_int(x.to_bigint().unwrap()))
+    let hash = hasher.finish();
+    Ok(vm.ctx.new_int(hash.to_bigint().unwrap()))
 }
 
 fn tuple_iter(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {