refactor(test): os_sep and remove_tree helpers

6 files changed, 30 insertions, 24 deletions

diff --git a/tests/helpers.py b/tests/helpers.py
index 1420bed7..185f20dd 100644
--- a/tests/helpers.py
+++ b/tests/helpers.py
@@ -9,6 +9,7 @@ import glob
 import os
 import os.path
 import re
+import shutil
 import subprocess
 import textwrap
 
@@ -95,6 +96,11 @@ def nice_file(*fparts):
     return os.path.normcase(os.path.abspath(os.path.realpath(fname)))
 
 
+def os_sep(s):
+    """Replace slashes in `s` with the correct separator for the OS."""
+    return s.replace("/", os.sep)
+
+
 class CheckUniqueFilenames:
     """Asserts the uniqueness of file names passed to a function."""
     def __init__(self, wrapped):
@@ -156,6 +162,14 @@ def remove_files(*patterns):
         for fname in glob.glob(pattern):
             os.remove(fname)
 
+def remove_tree(dirname):
+    """Remove a directory tree.
+
+    It's fine for the directory to not exist in the first place.
+    """
+    if os.path.exists(dirname):
+        shutil.rmtree(dirname)
+
 
 # Map chars to numbers for arcz_to_arcs
 _arcz_map = {'.': -1}
diff --git a/tests/mixins.py b/tests/mixins.py
index 4a3347b2..1043c2d2 100644
--- a/tests/mixins.py
+++ b/tests/mixins.py
@@ -10,13 +10,12 @@ Some of these are transitional while working toward pure-pytest style.
 import importlib
 import os
 import os.path
-import shutil
 import sys
 
 import pytest
 
 from coverage.misc import SysModuleSaver
-from tests.helpers import change_dir, make_file, remove_files
+from tests.helpers import change_dir, make_file, remove_files, remove_tree
 
 
 class PytestBase:
@@ -108,9 +107,7 @@ class RestoreModulesMixin:
         # resolution is only one second, a changed file might not be
         # picked up.
         remove_files("*.pyc", "*$py.class")
-        if os.path.exists("__pycache__"):
-            shutil.rmtree("__pycache__")
-
+        remove_tree("__pycache__")
         importlib.invalidate_caches()
 
 
diff --git a/tests/test_cmdline.py b/tests/test_cmdline.py
index caaa43c8..7b558bbb 100644
--- a/tests/test_cmdline.py
+++ b/tests/test_cmdline.py
@@ -3,7 +3,6 @@
 
 """Test cmdline.py for coverage.py."""
 
-import os
 import pprint
 import sys
 import textwrap
@@ -20,6 +19,7 @@ from coverage.exceptions import ExceptionDuringRun
 from coverage.version import __url__
 
 from tests.coveragetest import CoverageTest, OK, ERR, command_line
+from tests.helpers import os_sep
 
 
 class BaseCmdLineTest(CoverageTest):
@@ -818,7 +818,7 @@ class CmdLineStdoutTest(BaseCmdLineTest):
     @pytest.mark.skipif(env.JYTHON, reason="Jython gets mad if you patch sys.argv")
     def test_help_contains_command_name(self):
         # Command name should be present in help output.
-        fake_command_path = "lorem/ipsum/dolor".replace("/", os.sep)
+        fake_command_path = os_sep("lorem/ipsum/dolor")
         expected_command_name = "dolor"
         fake_argv = [fake_command_path, "sit", "amet"]
         with mock.patch.object(sys, 'argv', new=fake_argv):
@@ -834,7 +834,7 @@ class CmdLineStdoutTest(BaseCmdLineTest):
         # has the `__main__.py` file's patch as the command name. Instead, the command name should
         # be derived from the package name.
 
-        fake_command_path = "lorem/ipsum/dolor/__main__.py".replace("/", os.sep)
+        fake_command_path = os_sep("lorem/ipsum/dolor/__main__.py")
         expected_command_name = "dolor"
         fake_argv = [fake_command_path, "sit", "amet"]
         with mock.patch.object(sys, 'argv', new=fake_argv):
diff --git a/tests/test_filereporter.py b/tests/test_filereporter.py
index e2c71fa2..227cc458 100644
--- a/tests/test_filereporter.py
+++ b/tests/test_filereporter.py
@@ -3,23 +3,18 @@
 
 """Tests for FileReporters"""
 
-import os
 import sys
 
 from coverage.plugin import FileReporter
 from coverage.python import PythonFileReporter
 
 from tests.coveragetest import CoverageTest, UsingModulesMixin
+from tests.helpers import os_sep
 
 # pylint: disable=import-error
 # Unable to import 'aa' (No module named aa)
 
 
-def native(filename):
-    """Make `filename` into a native form."""
-    return filename.replace("/", os.sep)
-
-
 class FileReporterTest(UsingModulesMixin, CoverageTest):
     """Tests for FileReporter classes."""
 
@@ -55,9 +50,9 @@ class FileReporterTest(UsingModulesMixin, CoverageTest):
         acu = PythonFileReporter(aa)
         bcu = PythonFileReporter(aa.bb)
         ccu = PythonFileReporter(aa.bb.cc)
-        assert acu.relative_filename() == native("aa/__init__.py")
-        assert bcu.relative_filename() == native("aa/bb/__init__.py")
-        assert ccu.relative_filename() == native("aa/bb/cc/__init__.py")
+        assert acu.relative_filename() == os_sep("aa/__init__.py")
+        assert bcu.relative_filename() == os_sep("aa/bb/__init__.py")
+        assert ccu.relative_filename() == os_sep("aa/bb/cc/__init__.py")
         assert acu.source() == "# aa\n"
         assert bcu.source() == "# bb\n"
         assert ccu.source() == ""  # yes, empty
@@ -70,9 +65,9 @@ class FileReporterTest(UsingModulesMixin, CoverageTest):
         acu = PythonFileReporter(aa.afile)
         bcu = PythonFileReporter(aa.bb.bfile)
         ccu = PythonFileReporter(aa.bb.cc.cfile)
-        assert acu.relative_filename() == native("aa/afile.py")
-        assert bcu.relative_filename() == native("aa/bb/bfile.py")
-        assert ccu.relative_filename() == native("aa/bb/cc/cfile.py")
+        assert acu.relative_filename() == os_sep("aa/afile.py")
+        assert bcu.relative_filename() == os_sep("aa/bb/bfile.py")
+        assert ccu.relative_filename() == os_sep("aa/bb/cc/cfile.py")
         assert acu.source() == "# afile.py\n"
         assert bcu.source() == "# bfile.py\n"
         assert ccu.source() == "# cfile.py\n"
diff --git a/tests/test_process.py b/tests/test_process.py
index 29ce6071..bf16a2b2 100644
--- a/tests/test_process.py
+++ b/tests/test_process.py
@@ -23,7 +23,7 @@ from coverage.data import line_counts
 from coverage.files import abs_file, python_reported_file
 
 from tests.coveragetest import CoverageTest, TESTS_DIR
-from tests.helpers import change_dir, make_file, nice_file, re_lines, run_command
+from tests.helpers import change_dir, make_file, nice_file, os_sep, re_lines, run_command
 
 
 class ProcessTest(CoverageTest):
@@ -1378,7 +1378,7 @@ class UnicodeFilePathsTest(CoverageTest):
         report_expected = (
             "Name            Stmts   Miss  Cover\n" +
             "-----------------------------------\n" +
-            f"\xe2{os.sep}accented.py       1      0   100%\n" +
+            os_sep("\xe2/accented.py       1      0   100%\n") +
             "-----------------------------------\n" +
             "TOTAL               1      0   100%\n"
         )
diff --git a/tests/test_python.py b/tests/test_python.py
index 5965ca06..a8288613 100644
--- a/tests/test_python.py
+++ b/tests/test_python.py
@@ -3,7 +3,6 @@
 
 """Tests of coverage/python.py"""
 
-import os
 import sys
 
 import pytest
@@ -12,6 +11,7 @@ from coverage import env
 from coverage.python import get_zip_bytes, source_for_file
 
 from tests.coveragetest import CoverageTest
+from tests.helpers import os_sep
 
 
 class GetZipBytesTest(CoverageTest):
@@ -28,7 +28,7 @@ class GetZipBytesTest(CoverageTest):
         zip_file = "tests/zipmods.zip"
         sys.path.append(zip_file)       # So we can import the files.
         filename = zip_file + "/encoded_" + encoding + ".py"
-        filename = filename.replace("/", os.sep)
+        filename = os_sep(filename)
         zip_data = get_zip_bytes(filename)
         zip_text = zip_data.decode(encoding)
         assert 'All OK' in zip_text