relative_to: faster, simpler

Author: scivision

+stdlib/relative_to.m

@@ -16,6 +16,11 @@
   other {mustBeTextScalar}
 end
 
+if strempty(base) && strempty(other)
+  rel = ".";
+  return
+end
+
 if stdlib.has_python()
   rel = relative_to_python(base, other);
 elseif stdlib.dotnet_api() >= 5
@@ -29,11 +34,6 @@
 
 function rel = relative_to_dotnet(base, other)
 
-if strempty(base) && strempty(other)
-  rel = ".";
-  return
-end
-
 if strempty(other)
   rel = base;
   return
@@ -67,13 +67,7 @@
 function rel = relative_to_python(base, other)
 
 try
-  bp = py.pathlib.Path(other);
-  if stdlib.version_atleast(stdlib.python_version(), "3.12")
-    r = bp.relative_to(base, pyargs(walk_up=true));
-  else
-    r = bp.relative_to(base);
-  end
-  rel = string(py.str(r));
+  rel = string(py.os.path.relpath(other, base));
 catch e
   if e.identifier == "MATLAB:Python:PyException" && startsWith(e.message, 'Python Error: ValueError')
     rel = "";

test/TestRelative.m

@@ -37,7 +37,7 @@ function test_proximate_to(tc, pp)
 };
 % NOTE: ".." in relative_to(base) is ambiguous including for python.pathlib, C++ <filesystem>, etc.
 
-if stdlib.has_dotnet() || stdlib.version_atleast(stdlib.python_version(), "3.12")
+if stdlib.has_python() || stdlib.has_dotnet()
 p = [p, {
 {"a/b/c/d", "a/b", fullfile("..", "..")}, ...
 {"a/b", "a/c", fullfile("..", "c")}, ...
@@ -49,7 +49,7 @@ function test_proximate_to(tc, pp)
 
 if ispc
 
-if stdlib.has_dotnet() || stdlib.version_atleast(stdlib.python_version(), "3.12")
+if stdlib.has_python() || stdlib.has_dotnet()
 p = [p, { ...
 {"C:/a/b", "C:/", fullfile("..", "..")}, ...
 {"c:/a/b", "c:/a", ".."}, ...