[prettierx] flexible block brace style

Similar to --break-before-else option, please add an option for Stroustrup brace style. This would basically add breaks before certain statements, including else, catch, and finally. See ESLint’s Brace Style Documentation for examples.

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From @brodybits (May 2021):

• Looking at the eslint brace-style rule, I think it would be ideal to support the “Allman” as well as “Stroustrup” brace style.
• For discussion if we should support configuration per statement type, as was proposed for non-block statements in PR #327
• This may supersede the --break-before-else option from PR #224.

[shannonmoeller]

The stoustrup style applies to more than if/else blocks. It applies to any set of inseparable blocks.

Input:

if (conditionA) {
  // ...
} else if (conditionB) {
  // ...
} else {
  // ...
}

try {
  // ...
} catch (error) {
  // ...
} finally {
  // ...
}

do {
  // ...
} while (condition);

switch (value) {
  case 'a': {
    // ...
    break;
  } case 'b': {
    // ...
    break;
  } default: {
    // ...
    break;
  }
}

Output:

if (conditionA) {
  // ...
}
else if (conditionB) {
  // ...
}
else {
  // ...
}

try {
  // ...
}
catch (error) {
  // ...
}
finally {
  // ...
}

do {
  // ...
}
while (condition);

switch (value) {
  case 'a': {
    // ...
    break;
  }
  case 'b': {
    // ...
    break;
  }
  default: {
    // ...
    break;
  }
}

Basically there should be at least one break after any } that closes a block statement.

[shannonmoeller]

Should also respect comments:

// do this if we can
if (foo) {
  // ...
}
// otherwise do this
else {
  // ...
}