Macro assertables::assertable_command_stderr_eq

macro_rules! assertable_command_stderr_eq {
    ($left_command:expr, $right_command:expr $(,)?) => { ... };
    ($left_command:expr, $right_command:expr, $($arg:tt)+) => { ... };
}

Assert a command stderr string is equal to another.

• When true, return ().

• Otherwise, return Err with a message and the values of the expressions with their debug representations.

Examples

use std::process::Command;

let mut a = Command::new("printf");
let mut b = Command::new("printf");
let x = assertable_command_stderr_eq!(a, b);
//-> Ok(())
assert_eq!(x.unwrap(), ());

let mut a = Command::new("printf");
let mut b = Command::new("printf");
b.arg("-v");
let x = assertable_command_stderr_eq!(a, b);
//-> Err("…")
// assertable failed: `assertable_command_stderr_eq!(left_command, right_command)`
//   left command program: `\"printf\"`,
//  right command program: `\"printf\"`,
//   left stderr: `\"usage: printf format [arguments ...]\\n\"`,
//  right stderr: `\"printf: illegal option -- v\\nusage: printf format [arguments ...]\\n\"`
assert_eq!(x.unwrap_err(), "assertable failed: `assertable_command_stderr_eq!(left_command, right_command)`\n  left command program: `\"printf\"`,\n right command program: `\"printf\"`,\n  left stderr: `\"usage: printf format [arguments ...]\\n\"`,\n right stderr: `\"printf: illegal option -- v\\nusage: printf format [arguments ...]\\n\"`");

This macro has a second form where a custom message can be provided.