diff --git a/spec/python/test_debug_enum_name.py b/spec/python/test_debug_enum_name.py
index 7e8430bc..f36af9e6 100644
--- a/spec/python/test_debug_enum_name.py
+++ b/spec/python/test_debug_enum_name.py
@@ -3,7 +3,9 @@
 
 class TestDebugEnumName(unittest.TestCase):
     def test_debug_enum_name(self):
-        r = DebugEnumName.from_file("src/fixed_struct.bin")
+        with DebugEnumName.from_file('src/fixed_struct.bin') as r:
+            # --debug implies --no-auto-read
+            r._read()
 
-        # this test is meaningful only for languages that have --debug and do
-        # not save enum type info
+            # this test is meaningful only for languages that have --debug and do
+            # not save enum type info
diff --git a/spec/python/test_opaque_external_type.py b/spec/python/test_opaque_external_type.py
index 723839b1..a3365533 100644
--- a/spec/python/test_opaque_external_type.py
+++ b/spec/python/test_opaque_external_type.py
@@ -3,8 +3,7 @@
 
 class TestOpaqueExternalType(unittest.TestCase):
     def test_opaque_external_type(self):
-        r = OpaqueExternalType.from_file("src/term_strz.bin")
-
-        self.assertEqual(r.one.s1, "foo")
-        self.assertEqual(r.one.s2, "bar")
-        self.assertEqual(r.one.s3, "|baz@")
+        with OpaqueExternalType.from_file('src/term_strz.bin') as r:
+            self.assertEqual(r.one.s1, "foo")
+            self.assertEqual(r.one.s2, "bar")
+            self.assertEqual(r.one.s3, "|baz@")
diff --git a/spec/python/test_opaque_with_param.py b/spec/python/test_opaque_with_param.py
index 12c805d4..e7655e90 100644
--- a/spec/python/test_opaque_with_param.py
+++ b/spec/python/test_opaque_with_param.py
@@ -3,7 +3,6 @@
 
 class TestOpaqueWithParam(unittest.TestCase):
     def test_opaque_with_param(self):
-        r = OpaqueWithParam.from_file("src/term_strz.bin")
-
-        self.assertEqual(r.one.buf, "foo|b")
-        self.assertEqual(r.one.trailer, 0x61)
+        with OpaqueWithParam.from_file('src/term_strz.bin') as r:
+            self.assertEqual(r.one.buf, "foo|b")
+            self.assertEqual(r.one.trailer, 0x61)
diff --git a/spec/python/test_params_def.py b/spec/python/test_params_def.py
index eefa037f..5749bb9d 100644
--- a/spec/python/test_params_def.py
+++ b/spec/python/test_params_def.py
@@ -4,10 +4,7 @@
 
 class TestParamsDef(unittest.TestCase):
     def test_params_def(self):
-        io = KaitaiStream(open("src/term_strz.bin", "rb"))
-        r = ParamsDef(5, True, io, None, None)
-
-        self.assertEqual(r.buf, "foo|b")
-        self.assertEqual(r.trailer, 0x61)
-
-        io.close()
+        io = KaitaiStream(open('src/term_strz.bin', 'rb'))
+        with ParamsDef(5, True, io, None, None) as r:
+            self.assertEqual(r.buf, "foo|b")
+            self.assertEqual(r.trailer, 0x61)
diff --git a/spec/python/test_switch_cast.py b/spec/python/test_switch_cast.py
index bdf5a0f1..eb3eb142 100644
--- a/spec/python/test_switch_cast.py
+++ b/spec/python/test_switch_cast.py
@@ -3,8 +3,7 @@
 
 class TestSwitchCast(unittest.TestCase):
     def test_switch_cast(self):
-        r = SwitchCast.from_file("src/switch_opcodes.bin")
-
-        self.assertEqual(r.first_obj.value, "foobar")
-        self.assertEqual(r.second_val, 0x42)
-        # unable to test "err_cast" here
+        with SwitchCast.from_file('src/switch_opcodes.bin') as r:
+            self.assertEqual(r.first_obj.value, "foobar")
+            self.assertEqual(r.second_val, 0x42)
+            # unable to test "err_cast" here
diff --git a/spec/python/test_type_ternary_opaque.py b/spec/python/test_type_ternary_opaque.py
index 403e332a..0fd3993e 100644
--- a/spec/python/test_type_ternary_opaque.py
+++ b/spec/python/test_type_ternary_opaque.py
@@ -3,8 +3,7 @@
 
 class TestTypeTernaryOpaque(unittest.TestCase):
     def test_type_ternary_opaque(self):
-        r = TypeTernaryOpaque.from_file("src/term_strz.bin")
-
-        self.assertEqual(r.dif.s1, "foo")
-        self.assertEqual(r.dif.s2, "bar")
-        self.assertEqual(r.dif.s3, "|baz@")
+        with TypeTernaryOpaque.from_file('src/term_strz.bin') as r:
+            self.assertEqual(r.dif.s1, "foo")
+            self.assertEqual(r.dif.s2, "bar")
+            self.assertEqual(r.dif.s3, "|baz@")