fix integration tests

tests/cli.rs

@@ -1,10 +1,24 @@
 use std::error::Error;
 use assert_cmd::Command;
+use assert_cmd::assert::Assert;
 // use assert_cmd::prelude::*;
 use std::path::Path;
 use std::fs::read_to_string;
 
 type TestResult = Result<(), Box<dyn Error>>;
+type AssertResult = Result<Assert, Box<dyn Error>>;
+
+
+// pub fn args<I, S>(&mut self, args: I) -> &mut Self
+// where
+//     I: IntoIterator<Item = S>,
+//     S: AsRef<ffi::OsStr>,
+// ────────────────────────────────────────────────
+fn run_command(test_file: &str, cmd: &mut Command) -> AssertResult 
+{
+    let input = Path::new(test_file);
+    Ok(cmd.pipe_stdin(input)?.assert())
+}
 
 // empty stdin should return an empty line
 #[test]
@@ -49,16 +63,24 @@ fn fail_yargs_mismatch1() -> TestResult {
     Ok(())
 }
 
-
 // n args <= n cols
 #[test]
-fn cli_pass2() -> TestResult {
-    run_args("tests/inputs/input1", &["1", "2", "3", "4", "5", "6"])
+fn cli_pass2()  {
+    let mut cmd = Command::cargo_bin("yargs").unwrap();
+    cmd.args(&["-d", r"\s"])
+    .args(&["1", "2", "3", "4", "5", "6"]);
+    run_command("tests/inputs/input1", &mut cmd).unwrap()
+        .success();
 }
 
 #[test]
 #[should_panic]
 // more arguments passed than columns
-fn cli_fail1()  {
-    run_args("tests/inputs/input1", &["1", "2", "3", "4", "5", "6", "7", "8"]).unwrap()
+// delimiter: space
+fn cli_fail1() {
+    let mut cmd = Command::cargo_bin("yargs").unwrap();
+    cmd.args(&["-d", r"\s"])
+    .args(&["1", "2", "3", "4", "5", "6", "7", "8"]);
+    run_command("tests/inputs/input1", &mut cmd).unwrap()
+        .failure();
 }