Bug fix for sequential Writes, New File Writes

Author: rmliddle

tests/snippets/buffered_reader.py

@@ -0,0 +1,10 @@
+from io import BufferedReader, FileIO
+
+fi = FileIO('Cargo.toml')
+bb = BufferedReader(fi)
+
+result = bb.read()
+
+assert len(result) <= 8*1024
+assert len(result) >= 0
+

vm/src/stdlib/io.rs

@@ -111,7 +111,7 @@ fn file_io_init(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
 
     let os_mode = match mode.as_ref() {
         "r" => 0.to_bigint(),
-        _ => 1.to_bigint()
+        _ => 512.to_bigint()
     };
     let args = vec![name.clone(), vm.ctx.new_int(os_mode.unwrap())];
     let fileno = os_open(vm, PyFuncArgs::new(args, vec![]));
@@ -211,7 +211,14 @@ fn file_io_write(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     match obj.borrow_mut().kind {
         PyObjectKind::Bytes { ref mut value } => {
             match handle.write(&value[..]) {
-                Ok(len) => Ok(vm.ctx.new_int(len.to_bigint().unwrap())),
+                Ok(len) => {
+                    //reset raw fd on the FileIO object
+                    let new_handle = handle.into_raw_fd().to_bigint();
+                    vm.ctx.set_attr(&file_io, "fileno", vm.ctx.new_int(new_handle.unwrap()));
+
+                    //return number of bytes written
+                    Ok(vm.ctx.new_int(len.to_bigint().unwrap()))
+                }
                 Err(_) => Err(vm.new_value_error("Error Writing Bytes to Handle".to_string()))
             }
         },
@@ -267,7 +274,6 @@ fn text_io_base_read(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     }
 }
 
-
 pub fn io_open(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(
         vm, 

vm/src/stdlib/os.rs

@@ -12,10 +12,8 @@ use super::super::pyobject::{
     PyContext, PyFuncArgs, PyObjectRef, PyResult, TypeProtocol
 };
 
-
 use super::super::vm::VirtualMachine;
 
-
 pub fn os_open(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     arg_check!(
         vm,
@@ -42,7 +40,7 @@ pub fn os_open(vm: &mut VirtualMachine, args: PyFuncArgs) -> PyResult {
     if let Ok(f) = handle {
         Ok(vm.ctx.new_int(f.into_raw_fd().to_bigint().unwrap()))
     } else {
-        Err(vm.get_none())
+        Err(vm.new_value_error("Bad file descriptor".to_string()))
     }
 }
 
@@ -53,6 +51,6 @@ pub fn mk_module(ctx: &PyContext) -> PyObjectRef {
     ctx.set_attr(&py_mod, "O_WRONLY", ctx.new_int(1.to_bigint().unwrap()));
     ctx.set_attr(&py_mod, "O_RDWR", ctx.new_int(2.to_bigint().unwrap()));
     ctx.set_attr(&py_mod, "O_NONBLOCK", ctx.new_int(3.to_bigint().unwrap()));
-
+    ctx.set_attr(&py_mod, "O_CREAT", ctx.new_int(512.to_bigint().unwrap()));
     py_mod
 }