Utils: refactor format_infraction_with_duration and support absolute val

The absolute value is useful for preventing negative values in the case
that date_to is in the past relative to date_from.

* Add an absolute parameter to take the absolute value of the duration
* Rename expiry to date_to
* Rewrite the docstring

1 files changed, 23 insertions, 13 deletions

diff --git a/bot/utils/time.py b/bot/utils/time.py
index 7416f36e0..77060143c 100644
--- a/bot/utils/time.py
+++ b/bot/utils/time.py
@@ -114,30 +114,40 @@ def format_infraction(timestamp: str) -> str:
 
 
 def format_infraction_with_duration(
-    expiry: Optional[str],
+    date_to: Optional[str],
     date_from: Optional[datetime.datetime] = None,
-    max_units: int = 2
+    max_units: int = 2,
+    absolute: bool = True
 ) -> Optional[str]:
     """
-    Format an infraction timestamp to a more readable ISO 8601 format WITH the duration.
+    Return `date_to` formatted as a readable ISO-8601 with the humanized duration since `date_from`.
 
-    Returns a human-readable version of the duration between datetime.utcnow() and an expiry.
-    Unlike `humanize_delta`, this function will force the `precision` to be `seconds` by not passing it.
-    `max_units` specifies the maximum number of units of time to include (e.g. 1 may include days but not hours).
-    By default, max_units is 2.
+    `date_from` must be an ISO-8601 formatted timestamp. The duration is calculated as from
+    `date_from` until `date_to` with a precision of seconds. If `date_from` is unspecified, the
+    current time is used.
+
+    `max_units` specifies the maximum number of units of time to include in the duration. For
+    example, a value of 1 may include days but not hours.
+
+    If `absolute` is True, the absolute value of the duration delta is used. This prevents negative
+    values in the case that `date_to` is in the past relative to `date_from`.
     """
-    if not expiry:
+    if not date_to:
         return None
 
+    date_to_formatted = format_infraction(date_to)
+
     date_from = date_from or datetime.datetime.utcnow()
-    date_to = dateutil.parser.isoparse(expiry).replace(tzinfo=None, microsecond=0)
+    date_to = dateutil.parser.isoparse(date_to).replace(tzinfo=None, microsecond=0)
 
-    expiry_formatted = format_infraction(expiry)
+    delta = relativedelta(date_to, date_from)
+    if absolute:
+        delta = abs(delta)
 
-    duration = humanize_delta(relativedelta(date_to, date_from), max_units=max_units)
-    duration_formatted = f" ({duration})" if duration else ''
+    duration = humanize_delta(delta, max_units=max_units)
+    duration_formatted = f" ({duration})" if duration else ""
 
-    return f"{expiry_formatted}{duration_formatted}"
+    return f"{date_to_formatted}{duration_formatted}"
 
 
 def until_expiration(