chroot: move to clap from getopts (#1792)

+ add tests

tests/by-util/test_chroot.rs

@@ -1 +1,98 @@
-// ToDO: add tests
+use crate::common::util::*;
+
+#[test]
+fn test_missing_operand() {
+    let result = new_ucmd!().run();
+
+    assert_eq!(
+        true,
+        result
+            .stderr
+            .starts_with("error: The following required arguments were not provided")
+    );
+
+    assert_eq!(true, result.stderr.contains("<newroot>"));
+}
+
+#[test]
+fn test_enter_chroot_fails() {
+    let (at, mut ucmd) = at_and_ucmd!();
+
+    at.mkdir("jail");
+
+    let result = ucmd.arg("jail").run();
+
+    assert_eq!(
+        true,
+        result.stderr.starts_with(
+            "chroot: error: cannot chroot to jail: Operation not permitted (os error 1)"
+        )
+    )
+}
+
+#[test]
+fn test_no_such_directory() {
+    let (at, mut ucmd) = at_and_ucmd!();
+
+    at.touch(&at.plus_as_string("a"));
+
+    ucmd.arg("a")
+        .fails()
+        .stderr_is("chroot: error: cannot change root directory to `a`: no such directory");
+}
+
+#[test]
+fn test_invalid_user_spec() {
+    let (at, mut ucmd) = at_and_ucmd!();
+
+    at.mkdir("a");
+
+    let result = ucmd.arg("a").arg("--userspec=ARABA:").run();
+
+    assert_eq!(
+        true,
+        result.stderr.starts_with("chroot: error: invalid userspec")
+    );
+}
+
+#[test]
+fn test_preference_of_userspec() {
+    let scene = TestScenario::new(util_name!());
+    let result = scene.cmd("whoami").run();
+    if is_ci() && result.stderr.contains("No such user/group") {
+        // In the CI, some server are failing to return whoami.
+        // As seems to be a configuration issue, ignoring it
+        return;
+    }
+    println!("result.stdout {}", result.stdout);
+    println!("result.stderr = {}", result.stderr);
+    let username = result.stdout.trim_end();
+
+    let ts = TestScenario::new("id");
+    let result = ts.cmd("id").arg("-g").arg("-n").run();
+    println!("result.stdout {}", result.stdout);
+    println!("result.stderr = {}", result.stderr);
+
+    if is_ci() && result.stderr.contains("cannot find name for user ID") {
+        // In the CI, some server are failing to return id.
+        // As seems to be a configuration issue, ignoring it
+        return;
+    }
+
+    let group_name = result.stdout.trim_end();
+    let (at, mut ucmd) = at_and_ucmd!();
+
+    at.mkdir("a");
+
+    let result = ucmd
+        .arg("a")
+        .arg("--user")
+        .arg("fake")
+        .arg("-G")
+        .arg("ABC,DEF")
+        .arg(format!("--userspec={}:{}", username, group_name))
+        .run();
+
+    println!("result.stdout {}", result.stdout);
+    println!("result.stderr = {}", result.stderr);
+}