BytesIO readinto()

qingshi163 · qingshi163 · commit 8a539d03f6f4 · 2020-10-07T14:59:18.000+02:00
diff --git a/Lib/pickle.py b/Lib/pickle.py
@@ -218,7 +218,6 @@ def commit_frame(self, force=False):
         if self.current_frame:
             f = self.current_frame
             if f.tell() >= self._FRAME_SIZE_TARGET or force:
-                # XXX RUSTPYTHON TODO: memoryview + BytesIO.getbuffer()
                 # data = f.getbuffer()
                 data = f.getvalue()
                 write = self.file_write
@@ -1387,10 +1386,8 @@ def load_bytearray8(self):
         if len > maxsize:
             raise UnpicklingError("BYTEARRAY8 exceeds system's maximum size "
                                   "of %d bytes" % maxsize)
-        # XXX RUSTPYTHON TODO: BytesIO.readinto()
-        # b = bytearray(len)
-        # self.readinto(b)
-        b = self.read(len)
+        b = bytearray(len)
+        self.readinto(b)
         self.append(b)
     dispatch[BYTEARRAY8[0]] = load_bytearray8
 
diff --git a/vm/src/stdlib/io.rs b/vm/src/stdlib/io.rs
@@ -17,7 +17,7 @@ mod _io {
     use num_traits::ToPrimitive;
     use std::io::{self, prelude::*, Cursor, SeekFrom};
 
-    use crate::byteslike::PyBytesLike;
+    use crate::byteslike::{PyBytesLike, PyRwBytesLike};
     use crate::common::cell::{PyRwLock, PyRwLockWriteGuard};
     use crate::exceptions::{IntoPyException, PyBaseExceptionRef};
     use crate::function::{Args, KwArgs, OptionalArg, OptionalOption, PyFuncArgs};
@@ -1007,6 +1007,17 @@ mod _io {
             Ok(buf)
         }
 
+        #[pymethod]
+        fn readinto(self, obj: PyRwBytesLike, vm: &VirtualMachine) -> PyResult<usize> {
+            let mut buf = self.buffer(vm)?;
+            let ret = buf
+                .cursor
+                .read(&mut *obj.borrow_value())
+                .map_err(|_| vm.new_value_error("Error readinto from Take".to_owned()))?;
+
+            Ok(ret)
+        }
+
         //skip to the jth position
         #[pymethod]
         fn seek(
