Flat directory/module structure

src/format.rs

@@ -0,0 +1,65 @@
+use crate::units::{Second, Unit};
+
+/// Format the given duration as a string. The output-unit can be enforced by setting `unit` to
+/// `Some(target_unit)`. If `unit` is `None`, it will be determined automatically.
+pub fn format_duration(duration: Second, unit: Option<Unit>) -> String {
+    let (duration_fmt, _) = format_duration_unit(duration, unit);
+    duration_fmt
+}
+
+/// Like `format_duration`, but returns the target unit as well.
+pub fn format_duration_unit(duration: Second, unit: Option<Unit>) -> (String, Unit) {
+    let (out_str, out_unit) = format_duration_value(duration, unit);
+
+    (format!("{} {}", out_str, out_unit.short_name()), out_unit)
+}
+
+/// Like `format_duration`, but returns the target unit as well.
+pub fn format_duration_value(duration: Second, unit: Option<Unit>) -> (String, Unit) {
+    if (duration < 1.0 && unit.is_none()) || unit == Some(Unit::MilliSecond) {
+        (Unit::MilliSecond.format(duration), Unit::MilliSecond)
+    } else {
+        (Unit::Second.format(duration), Unit::Second)
+    }
+}
+
+#[test]
+fn test_format_duration_unit_basic() {
+    let (out_str, out_unit) = format_duration_unit(1.3, None);
+
+    assert_eq!("1.300 s", out_str);
+    assert_eq!(Unit::Second, out_unit);
+
+    let (out_str, out_unit) = format_duration_unit(1.0, None);
+
+    assert_eq!("1.000 s", out_str);
+    assert_eq!(Unit::Second, out_unit);
+
+    let (out_str, out_unit) = format_duration_unit(0.999, None);
+
+    assert_eq!("999.0 ms", out_str);
+    assert_eq!(Unit::MilliSecond, out_unit);
+
+    let (out_str, out_unit) = format_duration_unit(0.0, None);
+
+    assert_eq!("0.0 ms", out_str);
+    assert_eq!(Unit::MilliSecond, out_unit);
+
+    let (out_str, out_unit) = format_duration_unit(1000.0, None);
+
+    assert_eq!("1000.000 s", out_str);
+    assert_eq!(Unit::Second, out_unit);
+}
+
+#[test]
+fn test_format_duration_unit_with_unit() {
+    let (out_str, out_unit) = format_duration_unit(1.3, Some(Unit::Second));
+
+    assert_eq!("1.300 s", out_str);
+    assert_eq!(Unit::Second, out_unit);
+
+    let (out_str, out_unit) = format_duration_unit(1.3, Some(Unit::MilliSecond));
+
+    assert_eq!("1300.0 ms", out_str);
+    assert_eq!(Unit::MilliSecond, out_unit);
+}