Fix old python

Author: virtuald

src/semiwrap/autowrap/cxxparser.py

@@ -88,6 +88,8 @@
     TrampolineData,
 )
 
+from ..util import relpath_walk_up
+
 
 class HasSubpackage(Protocol):
     @property
@@ -2004,7 +2006,7 @@ def parse_header(
         extra_includes_first=user_cfg.extra_includes_first,
         extra_includes=user_cfg.extra_includes,
         inline_code=user_cfg.inline_code,
-        rel_fname=header_path.relative_to(header_root, walk_up=True).as_posix(),
+        rel_fname=relpath_walk_up(header_path, header_root).as_posix(),
     )
 
     # Parse the header using a custom visitor

src/semiwrap/cmd_genmeson.py

@@ -20,7 +20,7 @@
     LocalDependency,
     makeplan,
 )
-from .util import maybe_write_file
+from .util import maybe_write_file, relpath_walk_up
 
 # String escaping stolen from meson source code, Apache 2.0 license
 # This is the regex for the supported escape sequences of a regular string
@@ -150,12 +150,8 @@ def _render_include_directories(
     # meson wants these to be relative to meson.build
     # - only can do that if we're writing an output file
     if meson_build_path:
-        meson_build_parent = str(meson_build_path.parent)
-
-        # walk_up=True was introduced in Python 3.12
-        # incs = [p.relative_to(meson_build_parent, walk_up=True) for p in incs]
-
-        incs = [pathlib.Path(os.path.relpath(str(p), meson_build_parent)) for p in incs]
+        meson_build_parent = meson_build_path.parent
+        incs = [relpath_walk_up(p, meson_build_parent) for p in incs]
 
     _render_meson_args(
         r, "include_directories", [_make_string(inc.as_posix()) for inc in incs]

src/semiwrap/makeplan.py

@@ -14,6 +14,7 @@
 from .config.pyproject_toml import ExtensionModuleConfig, TypeCasterConfig
 from .pkgconf_cache import PkgconfCache
 from .pyproject import PyProject
+from .util import relpath_walk_up
 
 import toposort
 
@@ -608,7 +609,7 @@ def _locate_header(self, hdr: str, search_path: T.List[pathlib.Path]):
         for p in search_path:
             h_path = p / phdr
             if h_path.exists():
-                return InputFile(h_path.relative_to(self.project_root, walk_up=True)), p
+                return InputFile(relpath_walk_up(h_path, self.project_root)), p
         raise FileNotFoundError(
             f"cannot locate {phdr} in {', '.join(map(str, search_path))}"
         )

src/semiwrap/mkpc.py

@@ -2,6 +2,7 @@
 import typing as T
 
 from .pkgconf_cache import INITPY_VARNAME
+from .util import relpath_walk_up
 
 
 def make_pc_file(
@@ -29,7 +30,7 @@ def make_pc_file(
 
     for i, inc in enumerate(includes):
         includedir = project_root / pathlib.PurePosixPath(inc)
-        rel = includedir.relative_to(pc_install_path, walk_up=True)
+        rel = relpath_walk_up(includedir, pc_install_path)
         pc_content.append(f"inc{i}=${{prefix}}/{rel.as_posix()}")
         cflags.append(f"-I${{inc{i}}}")
 

src/semiwrap/util.py

@@ -1,3 +1,4 @@
+import os.path
 import pathlib
 import typing as T
 
@@ -18,3 +19,9 @@ def maybe_write_file(
         fp.write(content)
 
     return True
+
+
+def relpath_walk_up(p: pathlib.Path, other: pathlib.Path) -> pathlib.Path:
+    # walk_up=True was introduced in Python 3.12 so can't use that
+    #   p.relative_to(other, walk_up=True)
+    return pathlib.Path(os.path.relpath(p, other))