Represent subnetworks in network-area diagrams

[quinarygio]

Please check if the PR fulfills these requirements

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Does this PR already have an issue describing the problem?

Fixes #611

What kind of change does this PR introduce?

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Does this PR introduce a breaking change or deprecate an API?

• Yes
• No

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[So-Fras]

Thanks for the work!

As discussed together:

• It was not mentioned in the issue but it would be great if users could choose whether or not they want to highlight subnetworks. Maybe, via a new SvgParameters boolean attribute? The SvgWriter has already access to the SvgParameters. There can be a if condition using this new SvgParameters boolean that would trigger the duplication of lines and nodes (or not). Furthermore, this way, all the duplicated parts would be grouped together in the svg.

• The Graph should not be the object to hold information on style (it's only nodes and edges) --> the NetworkGraphBuilder class should not be affected by this PR

• The StyleProvider "family" should be the one affected by the PR. In the if condition in the SvgWriter mentioned above, we would call a new specific method of the StyleProvider for highlight. Thus, the StyleProvider does not need to "know" whether the user wants to highlight something or not.

[sonarqubecloud]

Quality Gate failed

Failed conditions
86.0% Coverage on New Code (required ≥ 90%)

See analysis details on SonarQube Cloud