Assert a command stderr string is equal to an expression.
use std::process::Command; let mut command = Command::new("bin/printf-stderr"); command.args(["%s", "hello"]); let s = String::from("hello"); assert_command_stderr_eq_expr!(command, s);
assert_command_stderr_eq_expr
assert_command_stderr_eq_expr_as_result
debug_assert_command_stderr_eq_expr