[New-bugs-announce] [issue9347] Calling argparse add_argument with a sequence as 'type' causes spurious error message

[Steven Bethard]

New submission from Steven Bethard <steven.bethard at gmail.com>:

What steps will reproduce the problem?

parser = argparse.ArgumentParser()
parser.add_argument('--foo', type=(int, float))

What is the expected output?

ValueError: (<type 'int'>, <type 'float'>) is not callable

What do you see instead?

TypeError: not all arguments converted during string formatting

Please provide any additional information below.

This is caused by calling using the % string formatting operator without
proper wrapping of the argument. The fix is basically:

-            raise ValueError('%r is not callable' % type_func)
+            raise ValueError('%r is not callable' % (type_func,))

----------
components: Library (Lib)
messages: 111316
nosy: bethard
priority: low
severity: normal
stage: needs patch
status: open
title: Calling argparse add_argument with a sequence as 'type' causes spurious error message
type: behavior
versions: Python 2.7, Python 3.2

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue9347>
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