ENH: handle generators in Series constructor close pandas-dev#1679

Author: wesm

RELEASE.rst

@@ -35,6 +35,7 @@ pandas 0.8.2
 
   - Add ``flags`` option for ``re.compile`` in some Series.str methods (#1659)
   - Parsing of UTC date strings in read_* functions (#1693)
+  - Handle generator input to Series (#1679)
 
 **API Changes**
 

pandas/core/series.py

@@ -8,6 +8,7 @@
 from itertools import izip
 import operator
 from distutils.version import LooseVersion
+import types
 
 from numpy import nan, ndarray
 import numpy as np
@@ -323,6 +324,8 @@ def __new__(cls, data=None, index=None, dtype=None, name=None,
                     data = lib.fast_multiget(data, index.values, default=np.nan)
             except TypeError:
                 data = [data.get(i, nan) for i in index]
+        elif isinstance(data, types.GeneratorType):
+            data = list(data)
 
         if dtype is not None:
             dtype = np.dtype(dtype)

pandas/tests/test_series.py

@@ -270,6 +270,18 @@ def test_constructor_series(self):
 
         assert_series_equal(s2, s1.sort_index())
 
+    def test_constructor_generator(self):
+        gen = (i for i in range(10))
+
+        result = Series(gen)
+        exp = Series(range(10))
+        assert_series_equal(result, exp)
+
+        gen = (i for i in range(10))
+        result = Series(gen, index=range(10, 20))
+        exp.index = range(10, 20)
+        assert_series_equal(result, exp)
+
     def test_constructor_maskedarray(self):
         data = ma.masked_all((3,), dtype=float)
         result = Series(data)