diff --git a/tests/importer/test_importer.py b/tests/importer/test_importer.py
index 9e61838..31b4705 100644
--- a/tests/importer/test_importer.py
+++ b/tests/importer/test_importer.py
@@ -10,6 +10,7 @@ import os
 import ast
 import tempfile
 from fractions import Fraction
+import pytest
 
 
 def test_basics():
@@ -50,6 +51,8 @@ def test_import_error_reporting():
     assert _import_error_test() is not None
 
 
+@pytest.mark.skipif(os.environ.get('PYTHONDONTWRITEBYTECODE'),
+                    reason="Bytecode generation is suppressed")
 def test_import_autocompiles():
     "Test that (import) byte-compiles the module."
 
diff --git a/tests/test_bin.py b/tests/test_bin.py
index abad9ca..7b34007 100644
--- a/tests/test_bin.py
+++ b/tests/test_bin.py
@@ -24,10 +24,12 @@ def hr(s=""):
 
 
 def run_cmd(cmd, stdin_data=None, expect=0, dontwritebytecode=False):
-    env = None
+    env = dict(os.environ)
     if dontwritebytecode:
-        env = dict(os.environ)
         env["PYTHONDONTWRITEBYTECODE"] = "1"
+    else:
+        env.pop("PYTHONDONTWRITEBYTECODE", None)
+
     cmd = shlex.split(cmd)
     cmd[0] = os.path.join(hy_dir, cmd[0])
     p = subprocess.Popen(cmd,