diff --git a/bin/dev_run_test b/bin/dev_run_test
index 6515c6b3..85a0d81c 100755
--- a/bin/dev_run_test
+++ b/bin/dev_run_test
@@ -1,3 +1,3 @@
 #!/bin/bash
 
-CIBW_PLATFORM=linux pytest $1
+CIBW_PLATFORM=linux pytest "$@"
diff --git a/bin/run_tests.py b/bin/run_tests.py
index e3275f3f..93c23e88 100755
--- a/bin/run_tests.py
+++ b/bin/run_tests.py
@@ -12,4 +12,4 @@ if __name__ == '__main__':
     subprocess.check_call([sys.executable, '-m', 'pytest', 'unit_test'])
 
     # run the integration tests
-    subprocess.check_call([sys.executable, '-m', 'pytest', '--durations', '0', 'test'])
+    subprocess.check_call([sys.executable, '-m', 'pytest', '-x', '--durations', '0', 'test'])
diff --git a/test/template_projects/base.py b/test/template_projects/base.py
index 2daf53a8..66e7acbc 100644
--- a/test/template_projects/base.py
+++ b/test/template_projects/base.py
@@ -21,7 +21,7 @@ class TemplateProject:
             file_path = os.path.join(path, filename)
             os.makedirs(os.path.dirname(file_path), exist_ok=True)
 
-            with io.open(file_path, 'w', encoding='utf8') as f:
+            with open(file_path, 'w', encoding='utf8') as f:
                 if isinstance(content, jinja2.Template):
                     content = content.render(self.template_context)
 
diff --git a/test/test_0_basic.py b/test/test_0_basic.py
index 5bf16822..a38c1180 100644
--- a/test/test_0_basic.py
+++ b/test/test_0_basic.py
@@ -21,7 +21,7 @@ def test(tmp_path):
     actual_wheels = utils.cibuildwheel_run(project_dir)
 
     # check that the expected wheels are produced
-    expected_wheels = utils.expected_wheels("spam", "0.1.0")
+    expected_wheels = utils.expected_wheels('spam', '0.1.0')
     assert set(actual_wheels) == set(expected_wheels)
 
 
diff --git a/test/test_cpp_standards.py b/test/test_cpp_standards.py
index b930acee..7dbca41a 100644
--- a/test/test_cpp_standards.py
+++ b/test/test_cpp_standards.py
@@ -72,15 +72,18 @@ MOD_INIT(spam)
 ''')
 
 
+cpp11_project = cpp_template_project.copy()
+cpp11_project.template_context['extra_compile_args'] = (
+    ['/std:c++11'] if utils.platform == 'windows' else ['-std=c++11']
+)
+cpp11_project.template_context['spam_cpp_top_level_add'] = '#include <array>'
+
+
 def test_cpp11(tmp_path):
     # This test checks that the C++11 standard is supported
     project_dir = tmp_path / 'project'
 
-    project = cpp_template_project.copy()
-    extra_compile_args = ['/std:c++11'] if utils.platform == 'windows' else ['-std=c++11']
-    project.template_context['extra_compile_args'] = extra_compile_args
-    project.template_context['spam_cpp_top_level_add'] = '#include <array>'
-    project.generate(project_dir)
+    cpp11_project.generate(project_dir)
 
     # VC++ for Python 2.7 does not support modern standards
     add_env = {'CIBW_SKIP': 'cp27-win* pp27-win32'}
@@ -92,15 +95,18 @@ def test_cpp11(tmp_path):
     assert set(actual_wheels) == set(expected_wheels)
 
 
+cpp14_project = cpp_template_project.copy()
+cpp14_project.template_context['extra_compile_args'] = (
+    ['/std:c++14'] if utils.platform == 'windows' else ['-std=c++14']
+)
+cpp14_project.template_context['spam_cpp_top_level_add'] = "int a = 100'000;"
+
+
 def test_cpp14(tmp_path):
     # This test checks that the C++14 standard is supported
     project_dir = tmp_path / 'project'
 
-    project = cpp_template_project.copy()
-    extra_compile_args = ['/std:c++14'] if utils.platform == 'windows' else ['-std=c++14']
-    project.template_context['extra_compile_args'] = extra_compile_args
-    project.template_context['spam_cpp_top_level_add'] = "int a = 100'000;"
-    project.generate(project_dir)
+    cpp14_project.generate(project_dir)
 
     # VC++ for Python 2.7 does not support modern standards
     # The manylinux1 docker image does not have a compiler which supports C++11
@@ -115,12 +121,9 @@ def test_cpp14(tmp_path):
 
 
 cpp17_project = cpp_template_project.copy()
-
-if utils.platform == 'windows':
-    cpp17_project.template_context['extra_compile_args'] = ['/std:c++17', '/wd5033']
-else:
-    cpp17_project.template_context['extra_compile_args'] = ['-std=c++17', '-Wno-register']
-
+cpp17_project.template_context['extra_compile_args'] = (
+    ['/std:c++17', '/wd5033'] if utils.platform == 'windows' else ['-std=c++17', '-Wno-register']
+)
 cpp17_project.template_context['spam_cpp_top_level_add'] = r'''
 #include <utility>
 auto a = std::pair(5.0, false);
diff --git a/test/test_ssl.py b/test/test_ssl.py
index eddb4074..18b9ebb6 100644
--- a/test/test_ssl.py
+++ b/test/test_ssl.py
@@ -28,4 +28,7 @@ def test(tmp_path):
     project_dir = tmp_path / 'project'
     project_with_ssl_tests.generate(project_dir)
 
-    utils.cibuildwheel_run(project_dir)
+    actual_wheels = utils.cibuildwheel_run(project_dir)
+
+    expected_wheels = utils.expected_wheels('spam', '0.1.0')
+    assert set(actual_wheels) == set(expected_wheels)
diff --git a/test/utils.py b/test/utils.py
index 1c2733c6..609ab9d7 100644
--- a/test/utils.py
+++ b/test/utils.py
@@ -33,7 +33,7 @@ def cibuildwheel_get_build_identifiers(project_path, env=None):
     for the current platform.
     '''
     cmd_output = subprocess.check_output(
-        [sys.executable, '-m', 'cibuildwheel', '--print-build-identifiers', str(project_path)],
+        [sys.executable, '-m', 'cibuildwheel', '--print-build-identifiers', project_path],
         universal_newlines=True,
         env=env,
     )