pyc_editor 0.4.6

A Rust library for reading, modifying, and writing Python .pyc files.
Documentation 
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use pyc_editor::{
    PycFile, dump_pyc, load_pyc,
    prelude::*,
    v310::{ext_instructions::ExtInstruction, opcodes::Opcode},
};

fn main() {
    let data = include_bytes!("./pyc_files/modify.cpython-310.pyc");

    let mut pyc_file = load_pyc(data.as_slice()).expect("Invalid pyc file");

    if let PycFile::V310(ref mut pyc) = pyc_file {
        // Call print(a + b) twice
        let mut resolved =
            pyc.code_object.code.to_resolved().expect(
                "This code is generated by the Python compiler and should never fail here.",
            );
        let (index, &call) = resolved
            .iter()
            .enumerate()
            .find(|(_, i)| i.get_opcode() == Opcode::CALL_FUNCTION)
            .expect("Call not found");

        resolved.insert_instructions(
            index,
            &[
                ExtInstruction::DupTop(0.into()), // Duplicate argument for the call (a + b)
                call,                             // Call print for the second time
            ],
        );

        pyc.code_object.code = resolved.to_instructions();
    }

    dbg!(&pyc_file); // Addition is changed to subtraction

    // You can now write it back to bytes
    let _out = dump_pyc(pyc_file).expect("Invalid pyc file");
}