Python: Add explicit tests for kwargs

I also renamed the arguments to match what the keyword argument is
called. It doesn't matter too much for these specific tests, but for the
tests I'm about to add, it makes things a lot easier to get an overview
of.

Oh, and a test failure :O

Author: RasmusWL

python/ql/test/library-tests/frameworks/stdlib/FileSystemAccess.py

@@ -2,21 +2,21 @@
 import io
 import os
 
-open("filepath")  # $ getAPathArgument="filepath"
-open(file="filepath")  # $ getAPathArgument="filepath"
+open("file")  # $ getAPathArgument="file"
+open(file="file")  # $ getAPathArgument="file"
 
 o = open
 
-o("filepath")  # $ getAPathArgument="filepath"
-o(file="filepath")  # $ getAPathArgument="filepath"
+o("file")  # $ getAPathArgument="file"
+o(file="file")  # $ getAPathArgument="file"
 
 
-builtins.open("filepath")  # $ getAPathArgument="filepath"
-builtins.open(file="filepath")  # $ getAPathArgument="filepath"
+builtins.open("file")  # $ getAPathArgument="file"
+builtins.open(file="file")  # $ getAPathArgument="file"
 
 
-io.open("filepath")  # $ getAPathArgument="filepath"
-io.open(file="filepath")  # $ getAPathArgument="filepath"
+io.open("file")  # $ getAPathArgument="file"
+io.open(file="file")  # $ getAPathArgument="file"
 
 f = open("path") # $ getAPathArgument="path"
 f.write("foo") # $ getAPathArgument="path" fileWriteData="foo"
@@ -30,21 +30,35 @@ def through_function(open_file):
 through_function(f)
 
 # os.path
-os.path.exists("filepath")  # $ getAPathArgument="filepath"
-os.path.isfile("filepath")  # $ getAPathArgument="filepath"
-os.path.isdir("filepath")  # $ getAPathArgument="filepath"
-os.path.islink("filepath")  # $ getAPathArgument="filepath"
-os.path.ismount("filepath")  # $ getAPathArgument="filepath"
+os.path.exists("path")  # $ getAPathArgument="path"
+os.path.exists(path="path")  # $ getAPathArgument="path"
+
+os.path.isfile("path")  # $ getAPathArgument="path"
+os.path.isfile(path="path")  # $ getAPathArgument="path"
+
+os.path.isdir("s")  # $ getAPathArgument="s"
+os.path.isdir(s="s")  # $ MISSING: getAPathArgument="s"
+
+os.path.islink("path")  # $ getAPathArgument="path"
+os.path.islink(path="path")  # $ getAPathArgument="path"
+
+os.path.ismount("path")  # $ getAPathArgument="path"
+os.path.ismount(path="path")  # $ getAPathArgument="path"
 
 # actual os.path implementations
 import posixpath
 import ntpath
 import genericpath
 
-posixpath.exists("filepath") # $ getAPathArgument="filepath"
-ntpath.exists("filepath") # $ getAPathArgument="filepath"
-genericpath.exists("filepath") # $ getAPathArgument="filepath"
+posixpath.exists("path") # $ getAPathArgument="path"
+posixpath.exists(path="path") # $ getAPathArgument="path"
+
+ntpath.exists("path") # $ getAPathArgument="path"
+ntpath.exists(path="path") # $ getAPathArgument="path"
+
+genericpath.exists("path") # $ getAPathArgument="path"
+genericpath.exists(path="path") # $ getAPathArgument="path"
 
 # os
-os.stat("filepath") # $ getAPathArgument="filepath"
-os.stat(path="filepath") # $ getAPathArgument="filepath"
+os.stat("path") # $ getAPathArgument="path"
+os.stat(path="path") # $ getAPathArgument="path"