1 files changed, 21 insertions, 3 deletions
diff --git a/python/problems/lists_and_for/substrings/common.py b/python/problems/lists_and_for/substrings/common.py
index 32a3d4c..bdc356a 100644
--- a/python/problems/lists_and_for/substrings/common.py
+++ b/python/problems/lists_and_for/substrings/common.py
@@ -27,12 +27,30 @@ hint_type = {
 }
 
 def test(python, code):
-    test_in = [1]
+    in_out = [
+        ('a', ['', 'a']),
+        ('ab', ['', 'a', 'b', 'ab']),
+        ('abc', ['', 'a', 'b', 'c', 'ab', 'bc', 'abc']),
+        ('tema', ['', 't', 'e', 'm', 'a', 'te', 'em', 'ma', 'tem', 'ema', 'tema']),
+    ]
+
+    test_in = [(None, s[0]+'\n') for s in in_out]
+    test_out = [str(s[1]) for s in in_out]
+    # List of outputs: (expression result, stdout, stderr, exception).
+    answers = python(code=code, inputs=test_in, timeout=1.0)
+    outputs = [ans[1] for ans in answers]
+
     n_correct = 0
+    tin = None
+    for i, (output, correct) in enumerate(zip(outputs, test_out)):
+        if correct in output:
+            n_correct += 1
+        else:
+            tin = test_in[i][1]
+            tout = correct
 
     passed = n_correct == len(test_in)
-    tin = None
-    tout = None
+
     hints = [{'id': 'test_results', 'args': {'passed': n_correct, 'total': len(test_in)}}]
     if tin:
         hints.append({'id': 'problematic_test_case', 'args': {'testin': str(tin), 'testout': str(tout)}})