Skip to content

Get io reader/writer classes only when needed #1021

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jun 8, 2019
Merged

Get io reader/writer classes only when needed #1021

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
39 changes: 22 additions & 17 deletions vm/src/stdlib/io.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -365,43 +365,48 @@ pub fn io_open(vm: &VirtualMachine, args: PyFuncArgs) -> PyResult {
}
};

let module = import::import_module(vm, PathBuf::default(), "io").unwrap();

// Class objects (potentially) consumed by io.open
// RawIO: FileIO
// Buffered: BufferedWriter, BufferedReader
// Text: TextIOWrapper
let file_io_class = vm.get_attribute(module.clone(), "FileIO").unwrap();
let buffered_writer_class = vm.get_attribute(module.clone(), "BufferedWriter").unwrap();
let buffered_reader_class = vm.get_attribute(module.clone(), "BufferedReader").unwrap();
let text_io_wrapper_class = vm.get_attribute(module, "TextIOWrapper").unwrap();
let io_module = import::import_module(vm, PathBuf::default(), "io").unwrap();

// Construct a FileIO (subclass of RawIOBase)
// This is subsequently consumed by a Buffered Class.
let file_args = vec![file.clone(), vm.ctx.new_str(mode.clone())];
let file_io_obj = vm.invoke(file_io_class, file_args)?;
let file_io_class = vm.get_attribute(io_module.clone(), "FileIO").unwrap();
let file_io_obj = vm.invoke(
file_io_class,
vec![file.clone(), vm.ctx.new_str(mode.clone())],
)?;

// Create Buffered class to consume FileIO. The type of buffered class depends on
// the operation in the mode.
// There are 3 possible classes here, each inheriting from the RawBaseIO
// creating || writing || appending => BufferedWriter
let buffered = match mode.chars().next().unwrap() {
'w' => vm.invoke(buffered_writer_class, vec![file_io_obj.clone()]),
'r' => vm.invoke(buffered_reader_class, vec![file_io_obj.clone()]),
'w' => {
let buffered_writer_class = vm
.get_attribute(io_module.clone(), "BufferedWriter")
.unwrap();
vm.invoke(buffered_writer_class, vec![file_io_obj.clone()])
}
'r' => {
let buffered_reader_class = vm
.get_attribute(io_module.clone(), "BufferedReader")
.unwrap();
vm.invoke(buffered_reader_class, vec![file_io_obj.clone()])
}
//TODO: updating => PyBufferedRandom
_ => unimplemented!("'a' mode is not yet implemented"),
};

let io_obj = match typ.chars().next().unwrap() {
// If the mode is text this buffer type is consumed on construction of
// a TextIOWrapper which is subsequently returned.
't' => vm.invoke(text_io_wrapper_class, vec![buffered.unwrap()]),

't' => {
let text_io_wrapper_class = vm.get_attribute(io_module, "TextIOWrapper").unwrap();
vm.invoke(text_io_wrapper_class, vec![buffered.unwrap()])
}
// If the mode is binary this Buffered class is returned directly at
// this point.
// For Buffered class construct "raw" IO class e.g. FileIO and pass this into corresponding field
'b' => buffered,

_ => unreachable!(),
};
io_obj
Expand Down