Merge pull request #1438 from lntuition/fix-byte-like-object

Add logic to check array.array byte like object

tests/snippets/ints.py

@@ -170,9 +170,20 @@ assert int.from_bytes(b'\xfc\x00', byteorder='big', signed=False) == 64512
 assert int.from_bytes(bytes=b'\xfc\x00', byteorder='big', signed=True) == -1024
 assert int.from_bytes(bytes=b'\xfc\x00', byteorder='big', signed=False) == 64512
 
+assert int.from_bytes([255, 0, 0], 'big') == 16711680
+assert int.from_bytes([255, 0, 0], 'little') == 255
+assert int.from_bytes([255, 0, 0], 'big', signed=False) == 16711680
+assert int.from_bytes([255, 0, 0], 'big', signed=True) == -65536
+
 with assert_raises(ValueError):
     int.from_bytes(b'\x00\x10', 'something')
 
+with assert_raises(ValueError):
+    int.from_bytes([256, 0, 0], 'big')
+
+with assert_raises(TypeError):
+    int.from_bytes(['something', 0, 0], 'big')
+
 assert (1024).to_bytes(4, 'big') == b'\x00\x00\x04\x00'
 assert (1024).to_bytes(2, 'little') == b'\x00\x04'
 assert (1024).to_bytes(4, byteorder='big') == b'\x00\x00\x04\x00'

vm/src/obj/objbyteinner.rs

@@ -26,6 +26,7 @@ use num_traits::ToPrimitive;
 
 use super::objbytearray::PyByteArray;
 use super::objbytes::PyBytes;
+use super::objlist::PyList;
 use super::objmemory::PyMemoryView;
 
 use super::objsequence;
@@ -47,6 +48,7 @@ impl TryFromObject for PyByteInner {
             k @ PyMemoryView => Ok(PyByteInner {
                 elements: k.get_obj_value().unwrap()
             }),
+            l @ PyList => l.get_byte_inner(vm),
             obj => Err(vm.new_type_error(format!(
                 "a bytes-like object is required, not {}",
                 obj.class()

vm/src/obj/objlist.rs

@@ -9,12 +9,13 @@ use num_traits::{One, Signed, ToPrimitive, Zero};
 use crate::function::OptionalArg;
 use crate::pyobject::{
     IdProtocol, PyClassImpl, PyContext, PyIterable, PyObjectRef, PyRef, PyResult, PyValue,
-    TryFromObject,
+    TryFromObject, TypeProtocol,
 };
 use crate::vm::{ReprGuard, VirtualMachine};
 
 use super::objbool;
-//use super::objint;
+use super::objbyteinner;
+use super::objint::PyIntRef;
 use super::objiter;
 use super::objsequence::{
     get_elements_list, get_item, seq_equal, seq_ge, seq_gt, seq_le, seq_lt, seq_mul, SequenceIndex,
@@ -96,6 +97,29 @@ impl PyList {
 
         start..stop
     }
+
+    pub fn get_byte_inner(&self, vm: &VirtualMachine) -> PyResult<objbyteinner::PyByteInner> {
+        let mut elements = Vec::<u8>::with_capacity(self.get_len());
+        for elem in self.elements.borrow().iter() {
+            match PyIntRef::try_from_object(vm, elem.clone()) {
+                Ok(result) => match result.as_bigint().to_u8() {
+                    Some(result) => elements.push(result),
+                    None => {
+                        return Err(
+                            vm.new_value_error("bytes must be in range (0, 256)".to_string())
+                        )
+                    }
+                },
+                _ => {
+                    return Err(vm.new_type_error(format!(
+                        "'{}' object cannot be interpreted as an integer",
+                        elem.class().name
+                    )))
+                }
+            }
+        }
+        Ok(objbyteinner::PyByteInner { elements })
+    }
 }
 
 #[derive(FromArgs)]