ps: Fix the time code (#172)

* ps: Fix the `time` code (uutils#160)

* ps: Fix the `time_test` code (uutils#160)

* ps: Add `[DD]-` format to the `time` and 'time_test' code (uutils#160)

* ps: Pass `cargo clippy` lint testing (uutils#160)

* ps: Beatify `test_time` code (uutils#160)

* ps: Format code (uutils#160)

* ps: Move time formatting logic to a new function `format_time`

* free: Fix incorrect `CachUse` value with `--line --wide`

* Revert "free: Fix incorrect `CachUse` value with `--line --wide`"

This reverts commit 5f6e0cbe67.

* ps: Change variables' names for `format_time` and beautify `test_time`

src/uu/ps/src/picker.rs

@@ -5,7 +5,6 @@
 
 use std::cell::RefCell;
 
-use chrono::DateTime;
 use uu_pgrep::process::{ProcessInformation, Teletype};
 
 pub(crate) fn collect_pickers(
@@ -54,13 +53,23 @@ fn time(proc_info: RefCell<ProcessInformation>) -> String {
     let cumulative_cpu_time = {
         let utime = proc_info.borrow_mut().stat()[13].parse::<i64>().unwrap();
         let stime = proc_info.borrow_mut().stat()[14].parse::<i64>().unwrap();
-        utime + stime
+        (utime + stime) / 100
     };
 
-    DateTime::from_timestamp_millis(cumulative_cpu_time)
-        .unwrap()
-        .format("%H:%M:%S")
-        .to_string()
+    format_time(cumulative_cpu_time)
+}
+
+fn format_time(seconds: i64) -> String {
+    let day = seconds / (3600 * 24);
+    let hour = (seconds % (3600 * 24)) / 3600;
+    let minute = (seconds % 3600) / 60;
+    let second = seconds % 60;
+
+    if day != 0 {
+        format!("{:02}-{:02}:{:02}:{:02}", day, hour, minute, second)
+    } else {
+        format!("{:02}:{:02}:{:02}", hour, minute, second)
+    }
 }
 
 fn cmd(proc_info: RefCell<ProcessInformation>) -> String {
@@ -70,3 +79,26 @@ fn cmd(proc_info: RefCell<ProcessInformation>) -> String {
 fn ucmd(proc_info: RefCell<ProcessInformation>) -> String {
     proc_info.borrow_mut().status().get("Name").unwrap().into()
 }
+
+#[test]
+fn test_time() {
+    let formatted = {
+        let time = {
+            let utime = 29i64;
+            let stime = 18439i64;
+            (utime + stime) / 100
+        };
+        format_time(time)
+    };
+    assert_eq!(formatted, "00:03:04");
+
+    let formatted = {
+        let time = {
+            let utime = 12345678i64;
+            let stime = 90i64;
+            (utime + stime) / 100
+        };
+        format_time(time)
+    };
+    assert_eq!(formatted, "01-10:17:37");
+}