Implement ask_uint() including tests

libimaginteraction/src/ask.rs

@@ -44,8 +44,31 @@ fn ask_bool_<R: BufRead>(s: &str, default: Option<bool>, input: &mut R) -> bool
     }
 }
 
-pub fn ask_uint(s: &str) -> u64 {
+/// Ask the user for an unsigned number. Optionally provide a default value. If none is provided,
-    unimplemented!()
+/// this keeps loop{}ing
+pub fn ask_uint(s: &str, default: Option<u64>) -> u64 {
+    ask_uint_(s, default, &mut BufReader::new(stdin()))
+}
+
+fn ask_uint_<R: BufRead>(s: &str, default: Option<u64>, input: &mut R) -> u64 {
+    use std::str::FromStr;
+
+    loop {
+        ask_question(s, false);
+
+        let mut s = String::new();
+        let _     = input.read_line(&mut s);
+
+        let u : Result<u64, _> = FromStr::from_str(&s[..]);
+        match u {
+            Ok(u)  => { return u; },
+            Err(_) => {
+                if default.is_some() {
+                    return default.unwrap();
+                } // else keep looping
+            }
+        }
+    }
 }
 
 pub fn ask_string(s: &str) -> String {
@@ -73,6 +96,7 @@ mod test {
     use std::io::BufReader;
 
     use super::ask_bool_;
+    use super::ask_uint_;
 
     #[test]
     fn test_ask_bool_nodefault_yes() {
@@ -146,4 +170,58 @@ mod test {
         assert!(true == ask_bool_(question, default, &mut BufReader::new(answers.as_bytes())));
     }
 
+    #[test]
+    fn test_ask_uint_nodefault() {
+        let question = "Is this 1";
+        let default  = None;
+        let answers  = "1";
+
+        assert!(1 == ask_uint_(question, default, &mut BufReader::new(answers.as_bytes())));
+    }
+
+    #[test]
+    fn test_ask_uint_default() {
+        let question = "Is this 1";
+        let default  = Some(1);
+        let answers  = "1";
+
+        assert!(1 == ask_uint_(question, default, &mut BufReader::new(answers.as_bytes())));
+    }
+
+    #[test]
+    fn test_ask_uint_default_2_input_1() {
+        let question = "Is this 1";
+        let default  = Some(2);
+        let answers  = "1";
+
+        assert!(1 == ask_uint_(question, default, &mut BufReader::new(answers.as_bytes())));
+    }
+
+    #[test]
+    fn test_ask_uint_default_2_noinput() {
+        let question = "Is this 1";
+        let default  = Some(2);
+        let answers  = "\n";
+
+        assert!(2 == ask_uint_(question, default, &mut BufReader::new(answers.as_bytes())));
+    }
+
+    #[test]
+    fn test_ask_uint_default_2_several_noinput() {
+        let question = "Is this 1";
+        let default  = Some(2);
+        let answers  = "\n\n\n\n";
+
+        assert!(2 == ask_uint_(question, default, &mut BufReader::new(answers.as_bytes())));
+    }
+
+    #[test]
+    fn test_ask_uint_default_2_wrong_input() {
+        let question = "Is this 1";
+        let default  = Some(2);
+        let answers  = "\n\n\nasfb\nsakjf\naskjf\n-2";
+
+        assert!(2 == ask_uint_(question, default, &mut BufReader::new(answers.as_bytes())));
+    }
+
 }