fix(12077) line breaking with unary operators in conditional

[islandryu]

Description

fix #12077

Unary operators within Conditional operators will break lines.
In other words, it does the same thing as the binary operator.

playground

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.

✨Try the playground for this PR✨

[islandryu]

I forgot to format the markdown, so I ran it.

[fisker]

There are lots of other UnaryOperators, if you mean to include them all, add more tests.

[islandryu]

@fisker
Thanks for the confirmation.
It's a little late now, but regardless of whether it's binary or unary, the line break position should be consistent, right?

// printWidth: 25
// input
const c = {
  prop1: foo == null ? bar : baz,
  prop2: !fooooooooo ? bar : baz,
// Should Identifier also have a new line?
  prop3: foooooooooo ? bar : baz,
};

// output
const c = {
  prop1:
    foo == null
      ? bar
      : baz,
  prop2:
    !fooooooooo
      ? bar
      : baz,
// Should Identifier also have a new line?
  prop3:
    foooooooooo
      ? bar
      : baz,
};

[fisker]

Should Identifier also have a new line?

Maybe we can try the opposite, instead of break before !fooooooooo, but remove new line before foo == null? There are too many cases to handle.

Prettier pr-12087
Playground link

--parser babel
--print-width 25

Input:

const x = {
  prop1: !fooooooooo ? bar : baz,
  prop1: fooooooooo ? bar : baz,
  prop1: foooo.oooo ? bar : baz,
  prop1: foooo.oo() ? bar : baz,
};

Output:

const x = {
  prop1:
    !fooooooooo
      ? bar
      : baz,
  prop1: fooooooooo
    ? bar
    : baz,
  prop1: foooo.oooo
    ? bar
    : baz,
  prop1: foooo.oo()
    ? bar
    : baz,
};

[islandryu]

@fisker
If we remove the new line before foo == null, we get this.

// printWidth: 18
// input
const x = {
  prop1: foo === null ? bar : baz,
  prop1: !fooooooooo ? bar : baz,
}

// output
const x = {
  prop1: foo ===
  null
    ? bar
    : baz,
  prop1:
    !fooooooooo
      ? bar
      : baz
}

Therefore, we changed the pattern so that all patterns have a new line.
Is there a problem if I change it so that all patterns have a new line?

[fisker]

Is there a problem if I change it so that all patterns have a new line?

I'm not familiar with this part, I don't know, sorry.

[fisker]

The output looks good, I'll check later.

[fisker]

I ran this change over some codebase, some case doesn't look good. mostly the variable declaration

-          const unwrappedInit = hasUnaryPrefix(init, '-')
-            ? init.argument
-            : init;
+          const unwrappedInit =
+            hasUnaryPrefix(init, '-') ? init.argument : init;

Full diff prettier/prettier-regression-testing#130

[islandryu]

If such a case exists, I guess I'll have to delete the new line before binaryExpression.

[islandryu]

Remove newline before binaryExpression. Existing tests have been affected.
It is not possible to make the newline constant for ternary operators without affecting existing tests.

[fisker]

It's fine to change the output.

[fisker]

Can you make the new tests longer to cross 80 width, so we can remove the printWidth? Or you can put new tests into a new directory, the snap became very big, hard to review.

[fisker]

I'm running this over other codebases, let's see how this effect them prettier/prettier-regression-testing#130 (comment)

[fisker]

The new output looks better to me. And changes in #12087 #10158 seems not effected 👍. Anyway, we need more review.

[islandryu]

I put the tests for printWidth: 18 and printWidth: 25 in a separate folder.