The original data is corrupted when we get a loading error

[mantid-builder]

Original Reporter: Arturs Bekasovs

This ticket is blocks : TRAC8547, TRAC8860

To reproduce:

1. Open MuonAnalysis.
2. Go to GroupingOptions tab and add a group with any name and detector IDs 1-50.
3. Go back to Home, and load an attached EMU data file. It contains data for 96 detectors, so it should be loaded without any problems.
4. Check that MuonAnalysis workspace contains data for 96 detectors.
5. Now try to load ''AutoTestData/emu00006473.nxs'' file. It has data for 32 detectors only hence specified grouping could not be applied, which should be indicated by the error thrown.

Now, you should notice that none of the widgets (e.g the Description) has updated to reflect the information for the new file, which is expected as file loading failed. However, if you check the MuonAnalysis workspace, it contains data for 32 detector only, which means that it was overwritten and the new data will be used if you continue using the interface. This shouldn't happen.

The general problem is that we load the new file straight to the ws used by the interface. If the file was loaded but an error occurs on a later stage we don't go further to update the interface, but we have already overwritten the original data.

[mantid-builder]

This issue was originally trac ticket 8020

[mantid-builder]

http://trac.mantidproject.org/mantid/raw-attachment/ticket/8020/EMU00036854.nxs
(uploaded by Arturs Bekasovs on 2013-09-25T09:43:43)

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