Merge pull request #54 from PickwickSoft/feature/add-convert-to-numeric-stream-operation

✨ Add convert to numeric stream operation

Author: garlontas

pystreamapi/_streams/__base_stream.py

@@ -251,6 +251,10 @@ def __map_to_str(self):
         """Converts the stream to strings."""
         self._map(str)
 
+    def numeric(self) -> NumericBaseStream:
+        """Returns a numeric stream. If the stream is already numeric, it is returned."""
+        return self._to_numeric_stream()
+
     @_operation
     def parallel(self) -> 'ParallelStream[K]':
         """Returns a parallel stream. If the stream is already parallel, it is returned."""

tests/test_stream_implementation.py

@@ -59,6 +59,14 @@ def test_map_to_str(self):
         result = self.stream([1, 2, 3, 9]).map_to_str().to_list()
         self.assertListEqual(result, ["1", "2", "3", "9"])
 
+    def test_convert_to_numeric_stream(self):
+        result = self.stream([1, 2, 3, 9]).numeric()
+        self.assertTrue(isinstance(result, NumericBaseStream))
+
+    def test_convert_to_numeric_stream_is_already_numeric(self):
+        result = self.stream([1.0, 2.0, 3.0, 9.0]).numeric()
+        self.assertTrue(isinstance(result, NumericBaseStream))
+
     def test_flat_map(self):
         result = self.stream([1, 2, 3, 9]).flat_map(lambda x: self.stream([x, x])).to_list()
         self.assertListEqual(result, [1, 1, 2, 2, 3, 3, 9, 9])