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

prettier plugin for the Ruby programming language

const {
  breakParent,
  concat,
  dedent,
  group,
  hardline,
  indent,
  join,
  line,
  literalline,
  softline,
  trim
} = require("../prettier");

function printBodyStmt(path, opts, print) {
  const [stmts, rescue, elseClause, ensure] = path.getValue().body;
  const parts = [];

  if (
    stmts.body.length > 1 ||
    stmts.body[0].type != "void_stmt" ||
    stmts.body[0].comments
  ) {
    parts.push(path.call(print, "body", 0));
  }

  if (rescue) {
    parts.push(dedent(concat([hardline, path.call(print, "body", 1)])));
  }

  if (elseClause) {
    // Before Ruby 2.6, this piece of bodystmt was an explicit "else" node
    const stmts =
      elseClause.type === "else"
        ? path.call(print, "body", 2, "body", 0)
        : path.call(print, "body", 2);

    parts.push(concat([dedent(concat([hardline, "else"])), hardline, stmts]));
  }

  if (ensure) {
    parts.push(dedent(concat([hardline, path.call(print, "body", 3)])));
  }

  return group(concat(parts));
}

const argNodeTypes = ["args", "args_add_star", "args_add_block"];

function printParen(path, opts, print) {
  const contentNode = path.getValue().body[0];

  if (!contentNode) {
    return "()";
  }

  let contentDoc = path.call(print, "body", 0);

  // If the content is params, we're going to let it handle its own parentheses
  // so that it breaks nicely.
  if (contentNode.type === "params") {
    return contentDoc;
  }

  // If we have an arg type node as the contents, then it's going to return an
  // array, so we need to explicitly join that content here.
  if (argNodeTypes.includes(contentNode.type)) {
    contentDoc = join(concat([",", line]), contentDoc);
  }

  return group(
    concat([
      "(",
      indent(concat([softline, contentDoc])),
      concat([softline, ")"])
    ])
  );
}

module.exports = {
  "@__end__": (path, _opts, _print) => {
    const { body } = path.getValue();
    return concat([trim, "__END__", literalline, body]);
  },
  bodystmt: printBodyStmt,
  paren: printParen,
  program: (path, opts, print) =>
    concat([join(hardline, path.map(print, "body")), hardline]),
  stmts: (path, opts, print) => {
    const stmts = path.getValue().body;

    // This is a special case where we have only comments inside a statement
    // list. In this case we want to avoid doing any kind of line number
    // tracking and just print out the comments.
    if (
      stmts.length === 1 &&
      stmts[0].type === "void_stmt" &&
      stmts[0].comments
    ) {
      const comments = path.map(
        (commentPath, index) => {
          stmts[0].comments[index].printed = true;
          return opts.printer.printComment(commentPath);
        },
        "body",
        0,
        "comments"
      );

      return concat([breakParent, join(hardline, comments)]);
    }

    const parts = [];
    let lineNo = null;

    stmts.forEach((stmt, index) => {
      if (stmt.type === "void_stmt") {
        return;
      }

      const printed = path.call(print, "body", index);

      if (lineNo === null) {
        parts.push(printed);
      } else if (
        stmt.start - lineNo > 1 ||
        [stmt.type, stmts[index - 1].type].includes("access_ctrl")
      ) {
        parts.push(hardline, hardline, printed);
      } else if (
        stmt.start !== lineNo ||
        path.getParentNode().type !== "string_embexpr"
      ) {
        parts.push(hardline, printed);
      } else {
        parts.push("; ", printed);
      }

      lineNo = stmt.end;
    });

    return concat(parts);
  }
};