REF: expose is_definitely_invalid_key()

Author: toobaz

pandas/_libs/index.pyx

@@ -28,7 +28,7 @@ from cpython.slice cimport PySlice_Check
 cdef int64_t iNaT = util.get_nat()
 
 
-cdef inline is_definitely_invalid_key(object val):
+cdef inline _is_definitely_invalid_key(object val):
     if PyTuple_Check(val):
         try:
             hash(val)
@@ -39,6 +39,8 @@ cdef inline is_definitely_invalid_key(object val):
     return (PySlice_Check(val) or cnp.PyArray_Check(val)
             or PyList_Check(val) or hasattr(val, '_data'))
 
+def is_definitely_invalid_key(val):
+    return _is_definitely_invalid_key(val)
 
 def get_value_at(ndarray arr, object loc):
     if arr.descr.type_num == NPY_DATETIME:
@@ -138,7 +140,7 @@ cdef class IndexEngine:
             util.set_value_at(arr, loc, value)
 
     cpdef get_loc(self, object val):
-        if is_definitely_invalid_key(val):
+        if _is_definitely_invalid_key(val):
             raise TypeError("'{val}' is an invalid key".format(val=val))
 
         if self.over_size_threshold and self.is_monotonic_increasing:
@@ -441,7 +443,7 @@ cdef class DatetimeEngine(Int64Engine):
         return algos.is_monotonic_int64(values, timelike=True)
 
     cpdef get_loc(self, object val):
-        if is_definitely_invalid_key(val):
+        if _is_definitely_invalid_key(val):
             raise TypeError
 
         # Welcome to the spaghetti factory
@@ -645,7 +647,7 @@ cdef class MultiIndexHashEngine(ObjectEngine):
         return algos.pad_object(values, other, limit=limit)
 
     cpdef get_loc(self, object val):
-        if is_definitely_invalid_key(val):
+        if _is_definitely_invalid_key(val):
             raise TypeError("'{val}' is an invalid key".format(val=val))
 
         self._ensure_mapping_populated()