Option to output module dependency tree

[rouson]

Description

I assume that fpm constructs some form of module dependency tree. It would be nice to have an option that prints the dependency tree for a project. This is especially useful for a developer who encounters a new project that doesn't have such information in the documentation. Specifically, if one is going to contribute to a project, dependency information can be really useful in determining the number of places that could be impacted by changes in one given place.

Possible Solution

Add a --dependency-tree flag that prompts the printing of whatever data structure fpm uses to store this information.

Additional Information

No response

[milancurcic]

Similar question in #682.

[rouson]

@milancurcic I just realized that #682 addresses a different topic but related topic. I'm referring to module dependencies, which might be mostly internal and could exist even in a project with no dependencies on external projects. I've added the word "module" in this issue's title and initial comment to make my request more clear. I'm seeking information that's useful for refactoring. Seeing a module dependency tree could be very helpful in determining which modules could be impacted by changes in any given module.

[ivan-pi]

Would something similar to Ninja's graph option meet your needs?

graph output a file in the syntax used by graphviz, an automatic graph layout tool. Use it like:

ninja -t graph mytarget | dot -Tpng -ograph.png

[...] If no target is given generate a graph for all root targets.

This uses the DOT language. Alternatively, we could make the output in trivial graph format.

Potentially a more powerful graph format could be used to capture groups like descendant submodules, folders, etc... or to annotate the modules with meta-data (number of exported procedures, LOC, or other software metrics). There are a lot of options for nice visualizations too (Cytoscape, NetworkX, ...).

[ivan-pi]

Here is a preview of the FPM modules using graphviz:

With dependencies includes: