Add support for function paramets without names

[odinuge]

Add support for flow functions with parameters that doesn't have a name.
Eg. value: string => void and value: (string, number) => void

This kind of functions ins't currently supported by react-docgen, and it's unable to parse the file.

Source: flow

[danez]

What do you think about instead of using '_' setting the field to null? It seems clearer to me that a consumer of react-docgen checks if the name === null instead of a "random" string name === '_'

[odinuge]

Hi @danez,

Got the inspiration from a flow-addon for atom (see screenshot). But I agree that null would be a better and cleaner value for working with the data afterwards. Will update the PR.

[odinuge]

Edit: getNameOrValue returns a string value, and therefore null would break flow. What do you think @danez?

[danez]

Hmm yes seems it is used quite a bit. We could maybe return an empty string? Then !name would work in the resulting documentation.
My intention is just that we should return something else than a non-empty string, because in the '_' case you would not be able to differ if the variable name was _ or empty.
And consumers could still default to _ in the empty case, if the do not display shorthands.

[odinuge]

Updated the PR setting the name to an empty string now.

[fkling]

Doing this here seems weird to me. I wouldn't expect getNameOrValue to be called with with a type annotation (but who knows...). It's also not quite right, since some FunctionTypeParam do have a name.

Personally I feel it makes more sense to fix this in getFlowType. If the name of the FunctionTypeParam is null, assign an empty string instead. Something like

name: param.node.name ? param.node.name.name || '';

@danez , why does this use getProperty to extract the name at the moment? Shouldn't it directly by getNameOrValue(param.get('name')) or just param.node.name.name?
Am I looking at the wrong syntax tree or am I missing a case here?

[danez]

Good question, I have no idea :) But seems unnecessary as it can never be computed or be a literal.

Doing name: param.node.name ? param.node.name.name || ''; should be correct in getFlowType unless the tests disagree.

[odinuge]

Hi @fkling,
After looking further into getFlowType, it makes more sense to do it your way with a simple inline ternary operator, instead of using the getNameOrValue. Updated the PR, and the tests still works as expected. 😄

[fkling]

Great, thank you all!