added terminal check

src/main.rs

@@ -1,4 +1,7 @@
-use std::process::exit;
+use std::{
+	io::{ stdout, IsTerminal },
+	process::exit
+};
 
 use pico_args::Arguments;
 
@@ -35,6 +38,11 @@ fn main() {
 		return;
 	}
 
+	if !stdout().is_terminal() {
+		println!("pride: output must be a terminal");
+		exit(2);
+	}
+
 	//	get small flag
 	let small = args.contains(["-s", "--small"]);