fix: timedelta parsing for int and floats

README.md

@@ -110,7 +110,7 @@ The following are all type-casting methods of `Env`:
 - `env.datetime`
 - `env.date`
 - `env.time`
-- `env.timedelta` (assumes value is an integer in seconds, or an ordered duration string like `7h7s` or `7w 7d 7h 7m 7s 7ms 7us`)
+- `env.timedelta` (assumes value is an float in seconds, or an ordered duration string like `7h7s` or `7w 7d 7h 7m 7s 7ms 7us`)
 - `env.url`
 - `env.uuid`
 - `env.log_level`

src/environs/__init__.py

@@ -40,7 +40,6 @@
 # - this pattern does not allow duplicate unit occurrences, GEP-2257 does
 # - this pattern allows for negative integers, GEP-2257 does not
 _TIMEDELTA_PATTERN = re.compile(
-    r"^(?:\s*)"  # optional whitespace at the beginning of the string
     r"(?:(-?\d+)\s*w\s*)?"  # weeks with optional whitespace around unit
     r"(?:(-?\d+)\s*d\s*)?"  # days with optional whitespace around unit
     r"(?:(-?\d+)\s*h\s*)?"  # hours with optional whitespace around unit
@@ -378,16 +377,34 @@ class TimeDeltaField(ma.fields.TimeDelta):
     def _deserialize(self, value, *args, **kwargs) -> timedelta:
         if isinstance(value, timedelta):
             return value
-        match = _TIMEDELTA_PATTERN.match(value)
-        if match is not None and match.group(0):  # disallow "", allow "0s"
+        if isinstance(value, str):
+            if value.strip() == "":
+                raise ma.ValidationError(
+                    "An empty string is not a valid period of time."
+                )
+            match = _TIMEDELTA_PATTERN.match(value.strip())
+            if match is not None:
+                return timedelta(
+                    weeks=int(match.group(1) or 0),
+                    days=int(match.group(2) or 0),
+                    hours=int(match.group(3) or 0),
+                    minutes=int(match.group(4) or 0),
+                    seconds=int(match.group(5) or 0),
+                    milliseconds=int(match.group(6) or 0),
+                    microseconds=int(match.group(7) or 0),
+                )
+            try:
+                value = float(value)
+            except ValueError:
+                raise ma.ValidationError("Not a valid period of time.") from None
+        if isinstance(value, bool):
+            raise ma.ValidationError("Not a valid period of time.")
+        if isinstance(value, (int, float)):
+            seconds = int(value)
+            milliseconds = int(value * 1000 % 1000)
             return timedelta(
-                weeks=int(match.group(1) or 0),
-                days=int(match.group(2) or 0),
-                hours=int(match.group(3) or 0),
-                minutes=int(match.group(4) or 0),
-                seconds=int(match.group(5) or 0),
-                milliseconds=int(match.group(6) or 0),
-                microseconds=int(match.group(7) or 0),
+                seconds=seconds,
+                milliseconds=milliseconds,
             )
         return super()._deserialize(value, *args, **kwargs)
 

tests/test_environs.py

@@ -229,26 +229,57 @@ def test_date_cast(self, set_env, env):
         assert env.date("DATE") == date
 
     def test_timedelta_cast(self, set_env, env):
-        # seconds as integer
+        # default as an integer, a float or a timedelta
+        assert env.timedelta("NO_VALUE", default=0) == dt.timedelta()
+        assert env.timedelta("NO_VALUE", default=42) == dt.timedelta(seconds=42)
+        assert env.timedelta("NO_VALUE", default=-42) == dt.timedelta(seconds=-42)
+        assert env.timedelta("NO_VALUE", default=42.3) == dt.timedelta(
+            seconds=42, milliseconds=300
+        )
+        assert env.timedelta(
+            "NO_VALUE", default=dt.timedelta(seconds=42)
+        ) == dt.timedelta(seconds=42)
+        assert env.timedelta(
+            "NO_VALUE", default=dt.timedelta(seconds=42, milliseconds=300)
+        ) == dt.timedelta(seconds=42, milliseconds=300)
+        # seconds as integer string
         set_env({"TIMEDELTA": "0"})
         assert env.timedelta("TIMEDELTA") == dt.timedelta()
+        assert env.timedelta("NO_VALUE", default="0") == dt.timedelta()
         set_env({"TIMEDELTA": "42"})
         assert env.timedelta("TIMEDELTA") == dt.timedelta(seconds=42)
+        assert env.timedelta("NO_VALUE", default="42") == dt.timedelta(seconds=42)
         set_env({"TIMEDELTA": "-42"})
         assert env.timedelta("TIMEDELTA") == dt.timedelta(seconds=-42)
+        assert env.timedelta("NO_VALUE", default="-42") == dt.timedelta(seconds=-42)
+        # seconds as a float string
+        set_env({"TIMEDELTA": "42.3"})
+        assert env.timedelta("TIMEDELTA") == dt.timedelta(seconds=42, milliseconds=300)
+        assert env.timedelta("NO_VALUE", default="42.3") == dt.timedelta(
+            seconds=42, milliseconds=300
+        )
         # seconds as duration string
         set_env({"TIMEDELTA": "0s"})
         assert env.timedelta("TIMEDELTA") == dt.timedelta()
+        assert env.timedelta("NO_VALUE", default="0s") == dt.timedelta()
         set_env({"TIMEDELTA": "42s"})
         assert env.timedelta("TIMEDELTA") == dt.timedelta(seconds=42)
+        assert env.timedelta("NO_VALUE", default="42s") == dt.timedelta(seconds=42)
         set_env({"TIMEDELTA": "-42s"})
         assert env.timedelta("TIMEDELTA") == dt.timedelta(seconds=-42)
+        assert env.timedelta("NO_VALUE", default="-42s") == dt.timedelta(seconds=-42)
         # whitespaces, units subselection (but descending ordering)
         set_env({"TIMEDELTA": " 42 d  -42s "})
         assert env.timedelta("TIMEDELTA") == dt.timedelta(days=42, seconds=-42)
+        assert env.timedelta("NO_VALUE", default=" 42 d  -42s ") == dt.timedelta(
+            days=42, seconds=-42
+        )
         # unicode µs (in addition to us below)
         set_env({"TIMEDELTA": "42µs"})
         assert env.timedelta("TIMEDELTA") == dt.timedelta(microseconds=42)
+        assert env.timedelta("NO_VALUE", default="42µs") == dt.timedelta(
+            microseconds=42
+        )
         # all supported units
         set_env({"TIMEDELTA": "42w 42d 42h 42m 42s 42ms 42us"})
         assert env.timedelta("TIMEDELTA") == dt.timedelta(
@@ -260,17 +291,35 @@ def test_timedelta_cast(self, set_env, env):
             milliseconds=42,
             microseconds=42,
         )
+        assert env.timedelta(
+            "NO_VALUE", default="42w 42d 42h 42m 42s 42ms 42us"
+        ) == dt.timedelta(
+            weeks=42,
+            days=42,
+            hours=42,
+            minutes=42,
+            seconds=42,
+            milliseconds=42,
+            microseconds=42,
+        )
         # empty string not allowed
         set_env({"TIMEDELTA": ""})
         with pytest.raises(environs.EnvError):
             env.timedelta("TIMEDELTA")
-        # float not allowed
-        set_env({"TIMEDELTA": "4.2"})
+        set_env({"TIMEDELTA": "something"})
         with pytest.raises(environs.EnvError):
             env.timedelta("TIMEDELTA")
         set_env({"TIMEDELTA": "4.2s"})
         with pytest.raises(environs.EnvError):
             env.timedelta("TIMEDELTA")
+        with pytest.raises(environs.EnvError):
+            env.timedelta("NO_VALUE", default="")
+        with pytest.raises(environs.EnvError):
+            env.timedelta("NO_VALUE", default="4.2s")
+        with pytest.raises(environs.EnvError):
+            env.timedelta("NO_VALUE", default=True)
+        with pytest.raises(environs.EnvError):
+            env.timedelta("NO_VALUE", default=dt.datetime.now())
 
     def test_time_cast(self, set_env, env):
         set_env({"TIME": "10:30"})