Virtual IO is a rust library for easily implementing stdin and stdout in a testable way. It replaces all println!
and print!
macro calls.
```rs use virtual_io::{VirtualIo, Vio};
fn getname() -> String { getnamebase(&mut virtualio::new()) }
fn getnamebase(vio: &mut impl VirtualIo) -> String { vio.print("What is your name? "); let name = vio.read_line(); vio.println(format!("Hello, {}!", name)); name }
mod test { use super::*; use virtual_io::VioFakeBuilder;
#[test]
fn test_get_name() {
// Create a fake version of vio that we can inject into the base
// function.
let mut vio = VioFakeBuilder::new()
// Add the expected io calls.
.expect_stdout("What is your name? ")
.provide_stdin("John")
.expect_stdout("Hello, John!\n")
// Build the fake vio.
.build();
// Assert that the return value is correct.
assert_eq!(get_name_base(&mut vio), "John");
// Assert that all io operations were identical to what was expected.
assert_eq!(vio.get_actual(), vio.get_expected());
}
} ```