[2.9.2] Missing whitespace in curly brackets

[boris-petrov]

Congrats on the new release! I've got a few regressions though.

Prettier-Java 2.9.2

Playground link

# Options (if any):

Input:

public abstract class Foo {
  @SuppressWarnings({ "a", "b" })
  public Object foo() {
	return new String[] { "a", "b" };
  }
}

Output:

public abstract class Foo {

	@SuppressWarnings({"a", "b"})
	public Object foo() {
		return new String[] {"a", "b"};
	}
}

Expected behavior:

public abstract class Foo {

  @SuppressWarnings({ "a", "b" })
  public Object foo() {
	return new String[] { "a", "b" };
  }
}

This might be on purpose - if so - I don't think the new behavior is better/more readable. There isn't a direct comparison with JavaScript but object literals, which use {, do have a space around the curlies.

[jtkiesel]

Thank you for thoroughly reporting all these regressions, and I apologize for the inconvenience caused by them! We had a rather major refactor to use tree-sitter for parsing, which changed a lot of our printer logic due to the syntax tree structure changing quite a bit.

These are all examples of array literals in Java, so I consider the direct JavaScript equivalent to be its array literals, which simply use square braces ([]) rather than curly braces ({}). These never render with spaces in Prettier JavaScript. For example:

Java Playground

final String[] array = {"a", "b", "c"};

vs

TypeScript Playground

const array: string[] = ["a", "b", "c"];

That being said, I'm happy to discuss further the pros/cons of this formatting. I didn't find it any worse personally, so I figured we should align more closely with Prettier JavaScript.

[boris-petrov]

You're absolutely right that these literals in Java are for arrays and that arrays in JavaScript are without whitespace. BUT this is semantics and Prettier shouldn't care about that - it should care only about syntax. And syntactically curlies are with whitespace in JS. And, that's personally my opinion, that looks much better than without whitespace.

P.S. Note also Python sets - they use the same syntax as Java arrays. And the community writes them with whitespace. :)

[jtkiesel]

this is semantics and Prettier shouldn't care about that - it should care only about syntax

That's an excellent point, I seem to have lost track of this and made the wrong call here. Thank you for your patience with me and for talking this through with me!

I'm also realizing Prettier has an option for this, bracketSpacing, which defaults to true, but can be set to false to remove the padding inside of {} for JS object literals. Perhaps I could implement that to allow users to remove the padding for Java array literals. But for now, I will revert this change to align with the syntactic formatting of Prettier JS.