wrong results with coupled telemac2d-tomawac run and using variable time step

Summary

When coupling TELEMAC-2D and TOMAWAC, a variable time step can be used in TELEMAC-2D. However, the coupling with TOMAWAC occurs at a fixed number of time steps, such that the time in TELEMAC-2D and TOMAWAC do not correspond. The issue was brought to my attention by Ateeq (Antea).

Environment

• Operating System: Windows/Linux/MacOS
• TELEMAC version: V8P5R0

Steps to reproduce

telemac2d.py my_case.cas --ncsize 4

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What is the current bug behaviour?

What is the expected correct behaviour?

Relevant logs and/or screenshots

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Possible fixes

I recommand to add an extra check in TELEMAC-2D, which will result in an error message when TELEMAC-2D is used with a variable time step and is coupled to TOMAWAC.