Hug object types in function parameters in Flow like in TS

[thorn0]

Description

Fixes #13395

Checklist

• I’ve added tests to confirm my change works.
• (If changing the API or CLI) I’ve documented the changes I’ve made (in the docs/ directory).
• (If the change is user-facing) I’ve added my changes to changelog_unreleased/*/XXXX.md file following changelog_unreleased/TEMPLATE.md.
• I’ve read the contributing guidelines.

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[thorn0]

Would be cool if path.match supported alternatives like this:

path.match(
  isObjectType,
  [
    [
      (node, name) => name === "typeAnnotation",
      (node, name) => name === "typeAnnotation"
    ],
    [
      (node, name) =>
        node.type === "FunctionTypeParam" && name === "typeAnnotation"
    ]
  ],
  shouldHugParameter
)

[fisker]

If function has .this and normal parameters, won't this pass on second parameter?

[fisker]

Use getFunctionParameters().indexOf?

[thorn0]

shouldHugFunctionParameters checks that there is only one parameter, but yes, doing what you propose would be easier to follow.

[fisker]

If shouldHugFunctionParameters only pass on one parameter. The number check is redundant. Only need make sure it's a parameter.

[fisker]

I'm a little bit confused, the "node" is a function, right? It can't be another function's parameter, how name can be "parameters"? The "name" is key of child?

[fisker]

Ah yes, this is different from callback of AstPath#each, the name is key of node there.

[thorn0]

Actually, getFunctionParameters().indexOf looks clumsy because I need to pass a node to it, and to get this node I have to use name and number anyway. So I'm going to simply remove the number check.

[thorn0]

I also renamed shouldHugFunctionParameters to shouldHugTheOnlyFunctionParameter to make it clear that it checks that there is only one parameter.

[sosukesuzuki]

👍