feat: Support max/min method for Time dtype

crates/polars-core/src/datatypes/dtype.rs

@@ -717,6 +717,8 @@ impl DataType {
             UInt64 => Scalar::from(u64::MAX),
             Float32 => Scalar::from(f32::INFINITY),
             Float64 => Scalar::from(f64::INFINITY),
+            #[cfg(feature = "dtype-time")]
+            Time => Scalar::new(Time, AnyValue::Time(NS_IN_DAY - 1)),
             dt => polars_bail!(ComputeError: "cannot determine upper bound for dtype `{}`", dt),
         };
         Ok(v)
@@ -737,6 +739,8 @@ impl DataType {
             UInt64 => Scalar::from(u64::MIN),
             Float32 => Scalar::from(f32::NEG_INFINITY),
             Float64 => Scalar::from(f64::NEG_INFINITY),
+            #[cfg(feature = "dtype-time")]
+            Time => Scalar::new(Time, AnyValue::Time(0)),
             dt => polars_bail!(ComputeError: "cannot determine lower bound for dtype `{}`", dt),
         };
         Ok(v)

py-polars/polars/datatypes/classes.py

@@ -448,6 +448,44 @@ class Time(TemporalType):
     The integer indicates the number of nanoseconds since midnight.
     """
 
+    @classmethod
+    def max(cls) -> pl.Expr:
+        """
+        Return a literal expression representing the maximum value of this data type.
+
+        Examples
+        --------
+        >>> pl.select(pl.Time.max() == 86_399_999_999_999)
+        shape: (1, 1)
+        ┌─────────┐
+        │ literal │
+        │ ---     │
+        │ bool    │
+        ╞═════════╡
+        │ true    │
+        └─────────┘
+        """
+        return pl.Expr._from_pyexpr(plr._get_dtype_max(cls))
+
+    @classmethod
+    def min(cls) -> pl.Expr:
+        """
+        Return a literal expression representing the minimum value of this data type.
+
+        Examples
+        --------
+        >>> pl.select(pl.Time.min() == 0)
+        shape: (1, 1)
+        ┌─────────┐
+        │ literal │
+        │ ---     │
+        │ bool    │
+        ╞═════════╡
+        │ true    │
+        └─────────┘
+        """
+        return pl.Expr._from_pyexpr(plr._get_dtype_min(cls))
+
 
 class Datetime(TemporalType):
     """

py-polars/tests/unit/test_datatypes.py

@@ -1,7 +1,7 @@
 from __future__ import annotations
 
 import pickle
-from datetime import datetime, timedelta
+from datetime import datetime, time, timedelta
 from typing import TYPE_CHECKING
 
 import pytest
@@ -217,12 +217,16 @@ def test_raise_invalid_namespace() -> None:
         (pl.UInt64, 0, 18446744073709551615),
         (pl.Float32, float("-inf"), float("inf")),
         (pl.Float64, float("-inf"), float("inf")),
+        (pl.Time, time(0, 0), time(23, 59, 59, 999999)),
     ],
 )
 def test_max_min(
-    dtype: datatypes.IntegerType | datatypes.Float32 | datatypes.Float64,
-    upper: int | float,
-    lower: int | float,
+    dtype: datatypes.IntegerType
+    | datatypes.Float32
+    | datatypes.Float64
+    | datatypes.Time,
+    upper: int | float | time,
+    lower: int | float | time,
 ) -> None:
     df = pl.select(min=dtype.min(), max=dtype.max())
     assert df.to_series(0).item() == lower