timer: import submodules only and add tests (#1075)

* timer: use import submodules only and add tests

* address ruff errors

* fix ruff error

* add recognizable numbers in tests

lib/timer.py

@@ -1,55 +1,56 @@
 """A timer for use in lichess-bot."""
-import time
-import datetime
+
+from datetime import datetime, timedelta
+from time import perf_counter
 from typing import Optional
 
 
-def msec(time_in_msec: float) -> datetime.timedelta:
+def msec(time_in_msec: float) -> timedelta:
     """Create a timedelta duration in milliseconds."""
-    return datetime.timedelta(milliseconds=time_in_msec)
+    return timedelta(milliseconds=time_in_msec)
 
 
-def to_msec(duration: datetime.timedelta) -> float:
+def to_msec(duration: timedelta) -> float:
     """Return a bare number representing the length of the duration in milliseconds."""
     return duration / msec(1)
 
 
-def msec_str(duration: datetime.timedelta) -> str:
+def msec_str(duration: timedelta) -> str:
     """Return a string with the duration value in whole number milliseconds."""
     return str(round(to_msec(duration)))
 
 
-def seconds(time_in_sec: float) -> datetime.timedelta:
+def seconds(time_in_sec: float) -> timedelta:
     """Create a timedelta duration in seconds."""
-    return datetime.timedelta(seconds=time_in_sec)
+    return timedelta(seconds=time_in_sec)
 
 
-def to_seconds(duration: datetime.timedelta) -> float:
+def to_seconds(duration: timedelta) -> float:
     """Return a bare number representing the length of the duration in seconds."""
     return duration.total_seconds()
 
 
-def sec_str(duration: datetime.timedelta) -> str:
+def sec_str(duration: timedelta) -> str:
     """Return a string with the duration value in whole number seconds."""
     return str(round(to_seconds(duration)))
 
 
-def minutes(time_in_minutes: float) -> datetime.timedelta:
+def minutes(time_in_minutes: float) -> timedelta:
     """Create a timedelta duration in minutes."""
-    return datetime.timedelta(minutes=time_in_minutes)
+    return timedelta(minutes=time_in_minutes)
 
 
-def hours(time_in_hours: float) -> datetime.timedelta:
+def hours(time_in_hours: float) -> timedelta:
     """Create a timedelta duration in hours."""
-    return datetime.timedelta(hours=time_in_hours)
+    return timedelta(hours=time_in_hours)
 
 
-def days(time_in_days: float) -> datetime.timedelta:
+def days(time_in_days: float) -> timedelta:
     """Create a timedelta duration in days."""
-    return datetime.timedelta(days=time_in_days)
+    return timedelta(days=time_in_days)
 
 
-def years(time_in_years: float) -> datetime.timedelta:
+def years(time_in_years: float) -> timedelta:
     """Create a timedelta duration in median years--i.e., 365 days."""
     return days(365) * time_in_years
 
@@ -68,36 +69,38 @@ class Timer:
     the timer was created or since it was last reset.
     """
 
-    def __init__(self, duration: datetime.timedelta = seconds(0),
-                 backdated_timestamp: Optional[datetime.datetime] = None) -> None:
+    __slots__ = ["duration", "starting_time"]
+
+    def __init__(self, duration: timedelta = seconds(0),
+                 backdated_timestamp: Optional[datetime] = None) -> None:
         """
         Start the timer.
 
         :param duration: The duration of time before Timer.is_expired() returns True.
         :param backdated_timestamp: When the timer should have started. Used to keep the timers between sessions.
         """
         self.duration = duration
-        self.reset()
-        if backdated_timestamp is not None:
-            time_already_used = datetime.datetime.now() - backdated_timestamp
-            self.starting_time -= to_seconds(time_already_used)
+        self.starting_time = perf_counter()
+
+        if backdated_timestamp:
+            self.starting_time -= to_seconds(datetime.now() - backdated_timestamp)
 
     def is_expired(self) -> bool:
         """Check if a timer is expired."""
         return self.time_since_reset() >= self.duration
 
     def reset(self) -> None:
         """Reset the timer."""
-        self.starting_time = time.perf_counter()
+        self.starting_time = perf_counter()
 
-    def time_since_reset(self) -> datetime.timedelta:
+    def time_since_reset(self) -> timedelta:
         """How much time has passed."""
-        return seconds(time.perf_counter() - self.starting_time)
+        return seconds(perf_counter() - self.starting_time)
 
-    def time_until_expiration(self) -> datetime.timedelta:
+    def time_until_expiration(self) -> timedelta:
         """How much time is left until it expires."""
         return max(seconds(0), self.duration - self.time_since_reset())
 
     def starting_timestamp(self, timestamp_format: str) -> str:
         """When the timer started."""
-        return (datetime.datetime.now() - self.time_since_reset()).strftime(timestamp_format)
+        return (datetime.now() - self.time_since_reset()).strftime(timestamp_format)

test_bot/test_timer.py

@@ -0,0 +1,95 @@
+"""Test functions dedicated to time measurement and conversion."""
+
+from datetime import datetime, timedelta
+
+from lib import timer
+
+
+def test_time_conversion() -> None:
+    """Test conversion of time units."""
+    assert timer.msec(1000) == timedelta(milliseconds=1000)
+    assert timer.to_msec(timedelta(milliseconds=1000)) == 1000
+
+    assert timer.msec_str(timedelta(milliseconds=1000)) == "1000"
+
+    assert timer.seconds(1) == timedelta(seconds=1)
+    assert timer.to_seconds(timedelta(seconds=1)) == 1
+
+    assert timer.sec_str(timedelta(seconds=1)) == "1"
+
+    assert timer.minutes(1) == timedelta(minutes=1)
+    assert timer.hours(1) == timedelta(hours=1)
+    assert timer.days(1) == timedelta(days=1)
+    assert timer.years(1) == timedelta(days=365)
+
+    assert timer.to_msec(timer.seconds(1)) == 1000
+    assert timer.to_seconds(timer.minutes(1)) == 60
+    assert timer.to_seconds(timer.hours(1)) == 60*60
+    assert timer.to_seconds(timer.days(1)) == 24*60*60
+    assert timer.to_seconds(timer.years(1)) == 365*24*60*60
+
+
+def test_init() -> None:
+    """Test Timer class init."""
+    t = timer.Timer()
+    assert t.duration == timedelta(0)
+    assert t.starting_time is not None
+
+    duration = timedelta(seconds=10)
+    t = timer.Timer(duration)
+    assert t.duration == duration
+    assert t.starting_time is not None
+
+    backdated_timestamp = datetime.now() - timedelta(seconds=10)
+    t = timer.Timer(backdated_timestamp=backdated_timestamp)
+    assert t.starting_time is not None
+    assert t.time_since_reset() >= timedelta(seconds=10)
+
+def test_is_expired() -> None:
+    """Test timer expiration."""
+    t = timer.Timer(timedelta(seconds=10))
+    assert not t.is_expired()
+
+    t = timer.Timer(timedelta(seconds=0))
+    assert t.is_expired()
+
+    t = timer.Timer(timedelta(seconds=10))
+    t.reset()
+    t.starting_time -= 10
+    assert t.is_expired()
+
+def test_reset() -> None:
+    """Test timer reset."""
+    t = timer.Timer(timedelta(seconds=10))
+    t.reset()
+    assert t.starting_time is not None
+    assert timer.sec_str(t.time_since_reset()) == timer.sec_str(timedelta(0))
+
+def test_time() -> None:
+    """Test time measurement, expiration, and time until expiration."""
+    t = timer.Timer(timedelta(seconds=10))
+    t.starting_time -= 5
+    assert timer.sec_str(t.time_since_reset()) == timer.sec_str(timedelta(seconds=5))
+
+    t = timer.Timer(timedelta(seconds=10))
+    t.starting_time -= 5
+    assert timer.sec_str(t.time_until_expiration()) == timer.sec_str(timedelta(seconds=5))
+
+    t = timer.Timer(timedelta(seconds=10))
+    t.starting_time -= 15  # Simulate time passing
+    assert t.time_until_expiration() == timedelta(0)
+
+    t = timer.Timer(timedelta(seconds=10))
+    t.starting_time -= 15
+    assert t.time_until_expiration() == timedelta(0)
+
+    t = timer.Timer(timedelta(seconds=10))
+    t.starting_time -= 5
+    assert timer.sec_str(t.time_until_expiration()) == timer.sec_str(timedelta(seconds=5))
+
+def test_starting_timestamp() -> None:
+    """Test timestamp conversion and integration."""
+    t = timer.Timer(timedelta(seconds=10))
+    timestamp_format = "%Y-%m-%d %H:%M:%S"
+    expected_timestamp = (datetime.now() - t.time_since_reset()).strftime(timestamp_format)
+    assert t.starting_timestamp(timestamp_format) == expected_timestamp