Fix argparse error for BooleanArgument with % in documentation

Python 3.14+ argparse treats % characters in help strings as format specifiers. When service model documentation contains % (e.g., IAM's UpdateAccountPasswordPolicy RequireSymbols parameter), argparse raises: ValueError: unsupported format character '^' (0x5e) at index 129

This was already fixed for CLIArgument in PR aws#9790 but BooleanArgument was missed. This commit adds the same .replace('%', '%%') escaping to BooleanArgument.add_to_parser() and adds a test to verify all service operations with % in documentation work correctly.

Fixes compatibility with Python 3.14+

Author: adev-code

awscli/arguments.py

@@ -593,7 +593,7 @@ def add_to_arg_table(self, argument_table):
     def add_to_parser(self, parser):
         parser.add_argument(
             self.cli_name,
-            help=self.documentation,
+            help=self.documentation.replace('%', '%%'),
             action=self._action,
             default=self._default,
             dest=self._destination,

tests/unit/test_argprocess.py

@@ -32,6 +32,9 @@
 from awscli.arguments import ListArgument, BooleanArgument
 from awscli.arguments import create_argument_model_from_schema
 
+from awscli.clidriver import ServiceOperation, CLIOperationCaller
+from awscli.argparser import ArgTableArgParser
+
 
 # These tests use real service types so that we can
 # verify the real shapes of services.
@@ -894,6 +897,28 @@ def test_json_value_decode_error(self):
         with self.assertRaises(ParamError):
             unpack_cli_arg(self.p, value)
 
+class TestPercentInDocumentation(BaseArgProcessTest):
+    def test_percent_characters_escaped_in_argument_help(self):
+        operation_caller = CLIOperationCaller(self.session)
+        for service_name in self.session.get_available_services():
+            service_model = self.session.get_service_model(service_name)
+            for operation_name in service_model.operation_names:
+                operation_model = service_model.operation_model(operation_name)
+                if not operation_model.input_shape:
+                    continue
+                has_percent = any(
+                    '%' in (member.documentation or '')
+                    for member in operation_model.input_shape.members.values()
+                )
+                if has_percent:
+                    service_op = ServiceOperation(
+                        name=xform_name(operation_name, '-'),
+                        parent_name=service_name,
+                        operation_caller=operation_caller,
+                        operation_model=operation_model,
+                        session=self.session,
+                    )
+                    ArgTableArgParser(service_op.arg_table)
 
 if __name__ == '__main__':
     unittest.main()