fix!: if_else and case_when now return Series

siuba/dply/verbs.py

@@ -683,9 +683,7 @@ def _if_else(__data, *args, **kwargs):
 def _if_else(cond, true_vals, false_vals):
     result = np.where(cond.fillna(False), true_vals, false_vals)
 
-    # TODO: should functions that take a Series, return a Series?
-    #       for now, just return "O" type. Sort out once better research.
-    return result
+    return pd.Series(result)
 
 
 # case_when ----------------
@@ -729,7 +727,7 @@ def case_when(__data, cases):
             out[:] = val_res
 
     # by recreating an array, attempts to cast as best dtype
-    return np.array(list(out))
+    return pd.Series(list(out))
 
 @case_when.register(Symbolic)
 @case_when.register(Call)