🐛 Fix shell_complete not working for Arguments

tests/assets/compat_arg_complete_click7_8.py

@@ -0,0 +1,22 @@
+import click
+import typer
+
+app = typer.Typer()
+
+
+def shell_complete(ctx: click.Context, param: click.Parameter, incomplete: str):
+    typer.echo(f"ctx: {ctx.info_name}", err=True)
+    typer.echo(f"arg is: {param.name}", err=True)
+    typer.echo(f"incomplete is: {incomplete}", err=True)
+    return ["Emma"]
+
+
+@app.command(context_settings={"auto_envvar_prefix": "TEST"})
+def main(name: str = typer.Argument(shell_complete=shell_complete)):
+    """
+    Say hello.
+    """
+
+
+if __name__ == "__main__":
+    app()

tests/test_compat/test_arg_completion.py

@@ -0,0 +1,28 @@
+import os
+import subprocess
+import sys
+
+from typer._compat_utils import _get_click_major
+
+from tests.assets import compat_arg_complete_click7_8 as mod
+
+
+def test_arg_completion():
+    result = subprocess.run(
+        [sys.executable, "-m", "coverage", "run", mod.__file__, "E"],
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+        encoding="utf-8",
+        env={
+            **os.environ,
+            "_COMPAT_ARG_COMPLETE_CLICK7_8.PY_COMPLETE": "complete_zsh",
+            "_TYPER_COMPLETE_ARGS": "compat_arg_complete_click7_8.py E",
+            "_TYPER_COMPLETE_TESTING": "True",
+        },
+    )
+    # TODO: when deprecating Click 7, remove second option
+    assert "Emma" in result.stdout or "_files" in result.stdout
+    if _get_click_major() > 7:
+        assert "ctx: compat_arg_complete_click7_8" in result.stderr
+        assert "arg is: name" in result.stderr
+        assert "incomplete is: E" in result.stderr

typer/main.py

@@ -936,6 +936,7 @@ def get_click_param(
                 expose_value=parameter_info.expose_value,
                 is_eager=parameter_info.is_eager,
                 envvar=parameter_info.envvar,
+                shell_complete=parameter_info.shell_complete,
                 autocompletion=get_param_completion(parameter_info.autocompletion),
                 # Rich settings
                 rich_help_panel=parameter_info.rich_help_panel,