@prettier/plugin-ruby/src/nodes/rescue.js

prettier plugin for the Ruby programming language

const {
  align,
  concat,
  group,
  hardline,
  indent,
  join,
  line
} = require("../prettier");
const { literal } = require("../utils");

function printBegin(path, opts, print) {
  return concat([
    "begin",
    indent(concat([hardline, concat(path.map(print, "body"))])),
    hardline,
    "end"
  ]);
}

function printEnsure(path, opts, print) {
  return concat([
    path.call(print, "body", 0),
    indent(concat([hardline, path.call(print, "body", 1)]))
  ]);
}

function printRescue(path, opts, print) {
  const [exception, variable, _stmts, addition] = path.getValue().body;
  const parts = ["rescue"];

  if (exception || variable) {
    if (exception) {
      if (Array.isArray(exception)) {
        // In this case, it's actually only the one exception (it's an array
        // of length 1).
        parts.push(" ", path.call(print, "body", 0, 0));
      } else {
        // Here we have multiple exceptions from which we're rescuing, so we
        // need to align them and join them together.
        const joiner = concat([",", line]);
        const exceptions = group(join(joiner, path.call(print, "body", 0)));

        parts.push(" ", align("rescue ".length, exceptions));
      }
    }

    if (variable) {
      parts.push(" => ", path.call(print, "body", 1));
    }
  } else {
    // If you don't specify an error to rescue in a `begin/rescue` block, then
    // implicitly you're rescuing from `StandardError`. In this case, we're
    // just going to explicitly add it.
    parts.push(" StandardError");
  }

  const rescueBody = path.call(print, "body", 2);

  if (rescueBody.parts.length > 0) {
    parts.push(indent(concat([hardline, rescueBody])));
  }

  // This is the next clause on the `begin` statement, either another
  // `rescue`, and `ensure`, or an `else` clause.
  if (addition) {
    parts.push(concat([hardline, path.call(print, "body", 3)]));
  }

  return group(concat(parts));
}

function printRescueMod(path, opts, print) {
  const [statementDoc, valueDoc] = path.map(print, "body");

  return concat([
    "begin",
    indent(concat([hardline, statementDoc])),
    hardline,
    "rescue StandardError",
    indent(concat([hardline, valueDoc])),
    hardline,
    "end"
  ]);
}

module.exports = {
  begin: printBegin,
  ensure: printEnsure,
  redo: literal("redo"),
  rescue: printRescue,
  rescue_mod: printRescueMod,
  retry: literal("retry")
};