improve path_tail and add tests

Author: scivision

+stdlib/+fileio/path_tail.m

@@ -2,19 +2,12 @@
 % get last part of directory path
 % if filename, return filename with suffix
 arguments
-  apath string
+  apath (1,:) string
 end
 
-k = strlength(apath) == 0;
-final(k) = "";
+import stdlib.fileio.absolute_path
 
-final(~k) = extractAfter(apath(~k), strlength(apath(~k))-1);
-
-i = final == "/" | final == "\";
-
-apath(i) = extractBefore(apath(i), strlength(apath(i)));
-
-[~, name, ext] = fileparts(apath);
+[~, name, ext] = fileparts(absolute_path(apath));
 
 last = append(name, ext);
 

+stdlib/TestFileio.m

@@ -25,6 +25,18 @@ function test_posix(tc)
 tc.verifyEmpty(posix(string.empty))
 end
 
+function test_path_tail(tc)
+
+import stdlib.fileio.path_tail
+
+tc.verifyEqual(path_tail("/foo/bar/baz"), "baz")
+tc.verifyEqual(path_tail("/foo/bar/baz/"), "baz")
+tc.verifyEqual(path_tail("/foo/bar/baz/."), "baz")
+tc.verifyEqual(path_tail("/foo/bar/baz/.."), "bar")
+tc.verifyEqual(path_tail("/foo/bar/baz.txt"), "baz.txt")
+
+end
+
 function test_is_absolute_path(tc)
 
 import stdlib.fileio.is_absolute_path