Fix absolute prefix/xxxdir subdir check on Windows

os.path.commonpath (and our implementation of it) both always return the
path using the native operating system path separator, so we can't just
directly compare it since the prefix could be specified in '/', and
commonpath would use '\' on Windows.

Also add a unit test for this.

1 files changed, 5 insertions, 1 deletions

diff --git a/run_unittests.py b/run_unittests.py
index e8659f4..aed1412 100755
--- a/run_unittests.py
+++ b/run_unittests.py
@@ -15,10 +15,11 @@
 
 import stat
 import shlex
-import unittest, os, sys, shutil, time
 import subprocess
 import re, json
 import tempfile
+import pathlib
+import unittest, os, sys, shutil, time
 from glob import glob
 import mesonbuild.compilers
 import mesonbuild.environment
@@ -169,6 +170,9 @@ class InternalTests(unittest.TestCase):
         self.assertEqual(commonpath(['/usr', '/bin']), sep)
         self.assertEqual(commonpath(['/usr', 'bin']), '')
         self.assertEqual(commonpath(['blam', 'bin']), '')
+        prefix = '/some/path/to/prefix'
+        libdir = '/some/path/to/prefix/libdir'
+        self.assertEqual(commonpath([prefix, libdir]), str(pathlib.PurePath(prefix)))
 
 
 class LinuxlikeTests(unittest.TestCase):