Fixed failure when reading integer option value from short form

.vscode/settings.json

@@ -17,6 +17,9 @@
 	"editor.renderWhitespace": "all",
 	"editor.rulers": [ 76 ],
 	"editor.tabSize": 2,
+	"files.insertFinalNewline": true,
+	"files.trimTrailingWhitespace": true,
+	"git.mergeEditor": false,
 	"files.exclude": {
  "**/__pycache__": true,
  "**/*.egg-info": true,

CHANGES.md

@@ -1,6 +1,12 @@
 # **CLASP.Python** Changes <!-- omit from toc -->
 
 
+## 0.8.12 - 28th July 2026
+
+* fixed falsy default values causing `MissingValueException` for option arguments;
+* fixed failure message to be passed to `MissingValueException`;
+
+
 ## 0.8.11 - 27th July 2026
 
 * ~ packaging & boilerplate improvements:

pyclasp/__init__.py

@@ -10,7 +10,7 @@
 __license__ = "BSD-3-Clause"
 __maintainer__ = "Matt Wilson"
 __status__ = "Beta"
-__version__ = "0.8.11"
+__version__ = "0.8.12"
 
 from .exceptions import *
 from .flag_specification import FlagSpecification, flag

pyclasp/option_argument.py

@@ -85,7 +85,7 @@ def _set_value(self, value, from_ctor=False):
 
  given_value = arg_spec.default_value
 
- if given_value:
+ if given_value is not None:
 
 
  if arg_spec.value_type:
@@ -148,7 +148,23 @@ def _set_value(self, value, from_ctor=False):
  pass
  else:
 
- raise MissingValueException("the '%s' option does not have a value to be interpreted as an integer" % (self.name))
+ if arg_spec.value_type == bool:
+
+ type_name = "boolean"
+ elif arg_spec.value_type == float:
+
+ type_name = "a number"
+ elif arg_spec.value_type == int:
+
+ type_name = "an integer"
+ elif _SUPPORT_long and arg_spec.value_type == long:
+
+ type_name = "a long integer"
+ else:
+
+ type_name = "a value"
+
+ raise MissingValueException("the '%s' option does not have a value to be interpreted as %s" % (self.name, type_name))
 
 
  self.given_value = given_value

setup.py

@@ -5,7 +5,7 @@
 
  name="pyclasp",
  python_requires='>=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*, !=3.5.*, !=3.6.*, !=3.7.*',
- version='0.8.11',
+ version='0.8.12',
 
  author="Matt Wilson",
  author_email="matthew@synesis.com.au",

tests/test_typed_values.py

@@ -303,10 +303,44 @@ def test_empty_option_value_of_type_int(self):
 
  argv = ( "myprog", "--length=" )
 
- with self.assertRaises(clasp.MissingValueException):
+ with self.assertRaises(clasp.MissingValueException) as ctx:
 
  clasp.parse(argv, specifications)
 
+ self.assertEqual("the '--length' option does not have a value to be interpreted as an integer", str(ctx.exception))
+
+
+ def test_empty_option_value_of_type_float(self):
+
+ specifications = (
+
+ clasp.option('--length', alias='-l', value_type=float),
+ )
+
+ argv = ( 'myprog', '--length=' )
+
+ with self.assertRaises(clasp.MissingValueException) as ctx:
+
+ clasp.parse(argv, specifications)
+
+ self.assertEqual("the '--length' option does not have a value to be interpreted as a number", str(ctx.exception))
+
+
+ def test_empty_option_value_of_type_bool(self):
+
+ specifications = (
+
+ clasp.option('--length', alias='-l', value_type=bool),
+ )
+
+ argv = ( 'myprog', '--length=' )
+
+ with self.assertRaises(clasp.MissingValueException) as ctx:
+
+ clasp.parse(argv, specifications)
+
+ self.assertEqual("the '--length' option does not have a value to be interpreted as boolean", str(ctx.exception))
+
 
  def test_empty_option_value_of_type_int_2(self):
 
@@ -442,6 +476,61 @@ def test_flags_of_flags_and_options_combined(self):
  self.assertEqual(0, len(args.values))
 
 
+ def test_reproduce_falsy_default_issue(self):
+
+ specifications = (
+ clasp.option(
+ "--depth",
+ alias="-d",
+ default=0,
+ value_type=int,
+ ),
+ clasp.option(
+ "--exchange",
+ alias="-e",
+ required=True,
+ value_type=str,
+ ),
+ )
+
+ argv = ('liquidity-assessor', '-e', 'bybit', '-d', '10')
+ args = clasp.parse(argv, specifications)
+
+ self.assertEqual(2, len(args.options))
+
+ depth_option = next(opt for opt in args.options if opt.name == '--depth')
+ self.assertEqual(10, depth_option.value)
+
+ exchange_option = next(opt for opt in args.options if opt.name == '--exchange')
+ self.assertEqual('bybit', exchange_option.value)
+
+
+ def test_reproduce_falsy_default_issue_with_default_used(self):
+
+ specifications = (
+ clasp.option(
+ "--depth",
+ alias="-d",
+ default=0,
+ value_type=int,
+ ),
+ clasp.option(
+ "--exchange",
+ alias="-e",
+ required=True,
+ value_type=str,
+ ),
+ )
+
+ argv = ('liquidity-assessor', '-e', 'bybit')
+ args = clasp.parse(argv, specifications)
+
+ # In CLASP, options with defaults are not automatically added to args.options unless specified on the CLI or if we lookup/access them?
+ # Wait, let's verify if they are added or not.
+ self.assertEqual(1, len(args.options))
+ exchange_option = args.options[0]
+ self.assertEqual('bybit', exchange_option.value)
+
 
 if '__main__' == __name__: