Crash on currency mass editing

[hsoft]

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Application Identifier: com.hardcoded_software.moneyguru
Application Version: 1.8.1

Traceback (most recent call last):
File "/Users/john/Downloads/moneyGuru.app/Contents/Resources/mg_cocoa.plugin/Contents/Resources/mg_cocoa.py", line 452, in savePanel
File "core/gui/base.pyc", line 162, in save
File "core/gui/mass_edition_panel.pyc", line 82, in _save
File "core/document.pyc", line 63, in wrapper
File "core/document.pyc", line 513, in change_transactions
File "core/document.pyc", line 144, in _change_transaction
File "core/model/transaction.pyc", line 138, in change
File "core/model/transaction.pyc", line 233, in amount
AssertionError
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I think it's because of remnants of the aborted split change.

[hsoft]

Yup, mass changing currencies of transactions with more than 2 splits cause this crash.

[hsoft]

(from [ffe22c274c5b]) [#151 state:fixed] Fixed a crash when mass changing currency of split transactions.
http://bitbucket.org/hsoft/moneyguru/changeset/ffe22c274c5b/