From 246d5ae53389e43fa4b25106b16bcfdfe340a9ce Mon Sep 17 00:00:00 2001
From: Sean MacAvaney <sean.macavaney@gmail.com>
Date: Sun, 23 Jan 2022 14:05:46 +0000
Subject: [PATCH] fixed bug with is_transformer

---
 pyterrier/transformer.py  |  2 +-
 tests/test_transformer.py | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 tests/test_transformer.py

diff --git a/pyterrier/transformer.py b/pyterrier/transformer.py
index ee52bea5..4f4e9bb9 100644
--- a/pyterrier/transformer.py
+++ b/pyterrier/transformer.py
@@ -16,7 +16,7 @@ def is_function(v):
     return isinstance(v, types.FunctionType)
 
 def is_transformer(v):
-    if isinstance(v, TransformerBase):
+    if isinstance(v, Transformer):
         return True
     return False
 
diff --git a/tests/test_transformer.py b/tests/test_transformer.py
new file mode 100644
index 00000000..1b6c7687
--- /dev/null
+++ b/tests/test_transformer.py
@@ -0,0 +1,19 @@
+import pyterrier as pt
+import unittest
+from .base import BaseTestCase
+import os
+import pandas as pd
+
+class TestTransformer(BaseTestCase):
+
+    def test_is_transformer(self):
+        class MyTransformer1(pt.Transformer):
+            pass
+        class MyTransformer2(pt.transformer.TransformerBase):
+            pass
+        class MyTransformer3(pt.transformer.IterDictIndexerBase):
+            pass
+        class MyTransformer4(pt.transformer.EstimatorBase):
+            pass
+        for T in [MyTransformer1, MyTransformer2, MyTransformer3, MyTransformer4]:
+            self.assertTrue(pt.transformer.is_transformer(T()))