Put the KVPs of identifiers and properties fields of resource shapes on their own lines

[brandondahler]

Background

What do these changes do?

Updates the formatting logic to put the key-value pairs of the identifiers and properties fields of resource shapes on individual lines instead of combining them onto a single line

Why are they important?

While the existing formatting works for simple single-identifier resources, resources with multiple identifiers quickly become unwieldy due to their identifiers being forced onto a single line.

For identifiers this is only an annoyance because most resources only have 1 or 2 identifiers. For properties, this can easily get out of hand because resources will generally have many resources.

For example, this is the current formatted version of a resource within a service I'm currently developing:

resource FooBar {
    identifiers: { fooId: FooId, FooBarId: FooBarId }
    properties: { previousFooBarId: FooBarId, fizz: String, buzz: String, baz: BazId, createdAt: Timestamp }
    create: CreateFooBar
    read: GetFooBar
    list: ListFooBar
}

My argument here is that the following format is more easy to parse as a reviewer:

resource FooBar {
    identifiers: {
        fooId: FooId
        FooBarId: FooBarId
    }
    properties: { 
        previousFooBarId: FooBarId
        fizz: String
        buzz: String
        baz: BazId
        createdAt: Timestamp 
    }
    create: CreateFooBar
    read: GetFooBar
    list: ListFooBar
}

Alternatives

An alternative I'm willing to look into implementing is updating the logic that currently forces all of the items of key-value pairs inside of objects into being smarter about when to place the items on a single line. A reasonable behavior in my opinion would be for it to keep values to a single line if there's only a single item, switching to the multi-line behavior when there's more than a single item.

Testing

• Updated and improved corpus tests for the formatter to verify the updated behavior works as expected

Links

• Resolves How to get smithy-format to keep resource identifiers and properties on separate lines #2104

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[JordonPhillips]

I'm okay with this, looks great! Thanks for the contribution!