From a23066443c73940c33aeb4b6ffd939f51ed17d16 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E8=B5=B5=E9=91=AB=E4=BA=BF?=
 <98445030+zhaoxinyi02@users.noreply.github.com>
Date: Thu, 13 Aug 2026 02:56:54 +0800
Subject: [PATCH] fix(cli): avoid triggering lazy getter during argparse
 validation
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Content-Type: text/plain; charset=UTF-8
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Python 3.14 added _check_help to ArgumentParser.add_argument
(see python/cpython#124899). It visits action.help during argument
registration, which made LazyChoices.help trigger the lazy
getter()/help_formatter() immediately — violating the lazy
contract and breaking test_lazy_choices_help on Python 3.14.

Detect the validation phase by looking for _check_help on the call
stack and skip the lazy computation there; the help string is still
lazily computed when argparse renders --help.

Fixes #1641

Signed-off-by: 赵鑫亿 <98445030+zhaoxinyi02@users.noreply.github.com>
---
 httpie/cli/utils.py | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/httpie/cli/utils.py b/httpie/cli/utils.py
index ad27da37f7..ba0ac40427 100644
--- a/httpie/cli/utils.py
+++ b/httpie/cli/utils.py
@@ -1,4 +1,5 @@
 import argparse
+import sys
 from typing import Any, Callable, Generic, Iterator, Iterable, Optional, TypeVar
 
 T = TypeVar('T')
@@ -54,12 +55,26 @@ def load(self) -> T:
         return self._obj
 
     @property
-    def help(self) -> str:
+    def help(self) -> Optional[str]:
+        # Python 3.14's argparse calls ``_check_help`` during
+        # ``add_argument``, which accesses ``action.help``. We must not
+        # trigger the lazy getter at that point. Detect the validation
+        # phase by looking for ``_check_help`` on the call stack; in any
+        # other context (e.g. rendering ``--help``) we lazily compute the
+        # help string via ``help_formatter``.
         if self._help is None and self.help_formatter is not None:
-            self._help = self.help_formatter(
-                self.load(),
-                isolation_mode=self.isolation_mode
-            )
+            frame = sys._getframe(1)
+            in_check_help = False
+            while frame is not None:
+                if frame.f_code.co_name == "_check_help":
+                    in_check_help = True
+                    break
+                frame = frame.f_back
+            if not in_check_help:
+                self._help = self.help_formatter(
+                    self.load(),
+                    isolation_mode=self.isolation_mode
+                )
         return self._help
 
     @help.setter