Make executable type better

regit/__main__.py

@@ -14,6 +14,27 @@ from dataclasses import dataclass, field
 # Some code borrowed from https://github.com/newren/git-filter-repo/blob/main/contrib/filter-repo-demos/lint-history
 
 
+class Executable(click.ParamType):
+    name = "executable"
+
+    def convert(self, value, param, ctx):
+        if "/" in value:
+            exe = Path(value)
+            exe = exe.absolute()
+            if not os.access(exe, os.X_OK):
+                self.fail(f"{value!r} is not an executable file", param, ctx)
+        else:
+            pp = shutil.which(value)
+            if pp is None:
+                self.fail(
+                    f"Could not find {value!r} on path, add './' if it is a file.",
+                    param,
+                    ctx,
+                )
+            exe = Path(pp)
+        return exe
+
+
 @contextmanager
 def blob_reader():
     process = subprocess.Popen(
@@ -44,7 +65,7 @@ class BlobHandler:
     is_relevant: Callable[[Path], bool] = lambda _: True
     transform: Callable[[Path, bytes], bytes] = lambda _, b: b
 
-    def __call__(self, commit, metadata):
+    def __call__(self, commit: fr.Commit, metadata):
         assert self.filter is not None
         for change in commit.file_changes:
             filename = Path(change.filename.decode("utf-8"))
@@ -111,7 +132,7 @@ def transform_program(program: Path, args: tuple[str], folder: Path):
 @click.argument(
     "program",
     # help="The program to execute on each file",
-    type=click.Path(executable=True, path_type=Path),
+    type=Executable(),
 )
 @click.argument(
     "args",
@@ -137,13 +158,6 @@ def regit(
     else:
         repo = git.Repo.clone_from(url=repo, to_path=output)
 
-    if program.exists():
-        program = program.absolute()
-    else:
-        pp = shutil.which(str(program))
-        assert pp is not None
-        program = Path(pp)
-
     os.chdir(output)
     options = fr.FilteringOptions.parse_args([], error_on_empty=False)