32679 fixed FindPeaks crash when the number of bins are not sufficient

[warunawickramasingha]

Description of work

Fixed a crash on FindPeaks algorithm when run on histograms containing a single bin by raising an error message on this condition.

Fixes #32679.

Further detail of work

To test:

1. Run the below code and the algorithm should not crash instead should throw a meaningful error

# import mantid algorithms, numpy and matplotlib
from mantid.simpleapi import *
import matplotlib.pyplot as plt
import numpy as np

ws = CreateWorkspace(OutputWorkspace='test', DataX='1', DataY='0,0,0,2,5,2,0,0,0,0', NSpec=10)

peaks_ws = FindPeaks(ws)

2. Errors should be raised even when the FindPeaks algorithm is run from Algorithms window on a similar workspace without crashing the workbench.

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[sf1919]

Please can you check whether the following warnings apply to this PR? The others I think are being fixed elsewhere

GNU C Compiler (Linux)

• FindPeaks.cpp

Clang Warnings (OSX)

• FindPeaks.cpp

The warnings have been resolved and therefore the specific changes requested have been dealt with. PR still needs reviewing in full though

[RichardWaiteSTFC]

Nice fix and thanks for adding a test. It would be good to have this check done in the validation but there is no input validation run before the exec in this algorithm and it doesn't seem worth it just for this fix. Just a minor thing then good to approve!

[RichardWaiteSTFC]

It's not necessary to print a warning as well as throw an error with the same message - it prints this

Block size of the workspace should be greater than:601
Error in execution of algorithm FindPeaks:
Block size of the workspace should be greater than:601

[warunawickramasingha]

Thanks for noting that! Did the changes as requested.

[RichardWaiteSTFC]

Thanks for the change looks good!

The base branch was changed.