Makes unittest use Path instead of os.path

This is for cross-platform compatibility when testing, since
os.path tends to mess up capitalisation of paths on windows
which are case-insensitive but pytest does not know that so we have
to use Path instead which yields more accurate results.

Author: gnikit

test/setup_tests.py

@@ -1,12 +1,10 @@
 import os
 import subprocess
 import sys
+from io import StringIO
+from pathlib import Path
 
-try:
-    from StringIO import StringIO
-except ImportError:
-    from io import StringIO
-root_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), ".."))
+root_dir = Path(__file__).parent.parent.resolve()
 sys.path.insert(0, root_dir)
 
 from fortls.jsonrpc import (  # noqa: E402, F401
@@ -19,7 +17,7 @@
 run_command = os.path.join(
     root_dir, "fortls.py --incremental_sync --use_signature_help"
 )
-test_dir = os.path.join(root_dir, "test", "test_source")
+test_dir = root_dir / "test" / "test_source"
 
 
 def run_request(request, fortls_args=""):

test/test_interface.py

@@ -1,5 +1,6 @@
 import os
 import sys
+from pathlib import Path
 
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
 
@@ -85,7 +86,7 @@ def test_command_line_code_actions_options():
 def unittest_server_init():
     from fortls.langserver import LangServer
 
-    root = os.path.join(os.path.dirname(__file__), "test_source")
+    root = (Path(__file__).parent / "test_source").resolve()
     parser = commandline_args("fortls")
     args = parser.parse_args("-c f90_config.json".split())
 
@@ -105,14 +106,14 @@ def test_config_file_general_options():
 
 
 def test_config_file_dir_parsing_options():
-    server, root = unittest_server_init()
+    server, r = unittest_server_init()
     # File parsing
     assert server.source_dirs == set(
-        [f"{root}/subdir", f"{root}/pp", f"{root}/pp/include"]
+        [f'{r/"subdir"}', f'{r/"pp"}', f'{r/"pp"/"include"}']
     )
     assert server.incl_suffixes == [".FF", ".fpc", ".h", "f20"]
     assert server.excl_suffixes == set(["_tmp.f90", "_h5hut_tests.F90"])
-    assert server.excl_paths == set([f"{root}/excldir", f"{root}/hover"])
+    assert server.excl_paths == set([f'{r/"excldir"}', f'{r/"hover"}'])
 
 
 def test_config_file_autocomplete_options():
@@ -145,7 +146,7 @@ def test_config_file_preprocessor_options():
     server, root = unittest_server_init()
     # Preprocessor options
     assert server.pp_suffixes == [".h", ".fh"]
-    assert server.include_dirs == set([f"{root}/include"])
+    assert server.include_dirs == set([f'{root/"include"}'])
     assert server.pp_defs == {
         "HAVE_PETSC": "",
         "HAVE_ZOLTAN": "",

test/test_preproc.py

@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-import os
+from pathlib import Path
 from setup_tests import (
     run_request,
     # path_to_uri,
@@ -26,17 +26,17 @@ def check_return(result_array, checks):
         for (i, check) in enumerate(checks):
             assert result_array[i]["contents"][0]["value"] == check
 
-    root_dir = os.path.join(test_dir, "pp")
-    string = write_rpc_request(1, "initialize", {"rootPath": root_dir})
-    file_path = os.path.join(test_dir, "pp", "preproc.F90")
+    root_dir = Path(test_dir).resolve() / "pp"
+    string = write_rpc_request(1, "initialize", {"rootPath": str(root_dir)})
+    file_path = str(root_dir / "preproc.F90")
     string += hover_req(file_path, 5, 8)  # user defined type
     string += hover_req(file_path, 7, 30)  # variable
     string += hover_req(file_path, 7, 40)  # multi-lin variable
     string += hover_req(file_path, 8, 7)  # function with if conditional
     string += hover_req(file_path, 9, 7)  # multiline function with if conditional
-    file_path = os.path.join(test_dir, "pp", "preproc_keywords.F90")
+    file_path = str(root_dir / "preproc_keywords.F90")
     string += hover_req(file_path, 6, 2)  # ignores PP across Fortran line continuations
-    errcode, results = run_request(string, f" --config={root_dir}/.pp_conf.json")
+    errcode, results = run_request(string, f' --config={root_dir/".pp_conf.json"}')
     assert errcode == 0
 
     # Reference solution