From 9b5e4c809e7e37fbdf82d3f6ccb580d4c5896c17 Mon Sep 17 00:00:00 2001
From: Eric Ihli <eihli@owoga.com>
Date: Tue, 12 Dec 2023 20:19:11 -0800
Subject: [PATCH] Initial commit

---
 .gitignore             |  2 ++
 parsearger/__init__.py | 40 ++++++++++++++++++++++++++++++++++++++++
 parsearger/__main__.py |  0
 parsearger/test.py     | 11 +++++++++++
 parsearger/test1.py    | 16 ++++++++++++++++
 5 files changed, 69 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 parsearger/__init__.py
 create mode 100644 parsearger/__main__.py
 create mode 100644 parsearger/test.py
 create mode 100644 parsearger/test1.py

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..36fa0f3
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+.pyc
+__pycache__
diff --git a/parsearger/__init__.py b/parsearger/__init__.py
new file mode 100644
index 0000000..9d4b3ee
--- /dev/null
+++ b/parsearger/__init__.py
@@ -0,0 +1,40 @@
+import argparse
+from typing import TypeVar, Generic, cast
+
+Value = TypeVar("Value")
+
+
+class Arg(Generic[Value]):
+    value: Value
+
+    def __init__(self, *args, **kwargs):
+        self.args = args
+        self.kwargs = kwargs
+
+    def __set_name__(self, owner, name):
+        owner.arguments.append(name)
+
+    def __get__(self, instance, owner) -> Value:
+        return self.value
+
+
+class TypedNamespace(argparse.Namespace):
+    arguments = []
+    @property
+    def descriptors(self):
+        return [(arg, self.__class__.__dict__[arg]) for arg in self.arguments]
+
+
+Namespace = TypeVar("Namespace", bound=argparse.Namespace)
+
+
+class ParseArger(argparse.ArgumentParser, Generic[Namespace]):
+    def __init__(self, *args, namespace: Namespace, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.namespace = namespace
+        if namespace is not None:
+            for name, descriptor in namespace.descriptors:
+                self.add_argument(f"--{name.replace('_', '-')}", *descriptor.args, **descriptor.kwargs)
+
+    def parse_args(self, args=None) -> Namespace:
+        return cast(Namespace, super().parse_args(args=args, namespace=self.namespace))
diff --git a/parsearger/__main__.py b/parsearger/__main__.py
new file mode 100644
index 0000000..e69de29
diff --git a/parsearger/test.py b/parsearger/test.py
new file mode 100644
index 0000000..269c45c
--- /dev/null
+++ b/parsearger/test.py
@@ -0,0 +1,11 @@
+from parsearger import ParseArger, Arg, TypedNamespace
+
+class CliArgs(TypedNamespace):
+    num_things = Arg[int](help="Some help message", type=int)
+    name_thing = Arg[str](help="Name of some thing")
+
+namespace = CliArgs()
+parser = ParseArger(namespace=namespace)
+args = parser.parse_args()
+args.num_things
+args.name_thing
diff --git a/parsearger/test1.py b/parsearger/test1.py
new file mode 100644
index 0000000..29e2557
--- /dev/null
+++ b/parsearger/test1.py
@@ -0,0 +1,16 @@
+from collections import namedtuple
+import argparse
+parser = argparse.ArgumentParser()
+parser.add_argument("--num-things", help="Number of things", type=int)
+args.num_things
+
+parser = argparse.ArgumentParser()
+parser.add_argument('--some-arg')
+parser.add_argument('--another-arg')
+MagicNamespace = namedtuple('MagicNamespace', [act.dest for act in parser._actions])
+mn = MagicNamespace()
+mn.some_arg
+mn.foo
+parsed = parser.parse_args(['--some-arg', 'val1', '--another-arg', 'val2'], namespace=mn)
+parsed.some_arg
+parsed.foo