Merge pull request #654 from CoffeaTeam/emptylookup

Better lookup error
CoffeaTeam · Mar 29, 2022 · 57f6130 · 57f6130
2 parents a3ba69e + 29f44cd
commit 57f6130
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diff --git a/coffea/lookup_tools/dense_lookup.py b/coffea/lookup_tools/dense_lookup.py
@@ -30,6 +30,8 @@ def __init__(self, values, dims, feval_dim=None):
         self._values = deepcopy(values)
 
     def _evaluate(self, *args):
+        if len(args) != self._dimension:
+            raise ValueError(f"Insufficient arguments for correction {self}")
         indices = []
         if self._dimension == 1:
             axes = (

diff --git a/tests/test_lookup_tools.py b/tests/test_lookup_tools.py
@@ -3,6 +3,7 @@
 import os
 from coffea import lookup_tools
 import awkward as ak
+import pytest
 from coffea.util import numpy as np
 from coffea.nanoevents import NanoEventsFactory
 
@@ -458,6 +459,10 @@ def test_dense_lookup():
         numpy.ones(shape=(3, 4)), (numpy.linspace(0, 1, 4), numpy.linspace(0, 1, 5))
     )
 
+    with pytest.raises(ValueError):
+        lookup(ak.Array([]))
+
+    assert ak.to_list(lookup(ak.Array([]), ak.Array([]))) == []
     assert lookup(0.1, 0.3) == 1.0
     assert numpy.all(lookup(0.1, numpy.array([0.3, 0.5])) == numpy.array([1.0, 1.0]))
     assert ak.to_list(lookup(a, a)) == [[1.0, 1.0], [1.0]]