@tpzdsp/eslint-config-dsp/eslint/rules/padding-before-block-statement.js

re-usable config for ESLint, Prettier and semantic-release

export default {
  meta: {
    type: 'layout',
    docs: {
      description:
        'Require blank lines before block statements unless they are the first statement in a block',
    },
    fixable: 'whitespace',
    schema: [],
    messages: {
      missingPadding: 'Expected blank line before this {{keyword}} statement.',
    },
  },

  create: (context) => {
    const checkPadding = (node) => {
      if (!node.loc || !node.parent) {
        return;
      }

      const parent = node.parent;

      if (parent.type !== 'BlockStatement' && parent.type !== 'Program') {
        return;
      }

      const body = parent.body;

      if (!Array.isArray(body)) {
        return;
      }

      const index = body.indexOf(node);

      if (index === -1 || index === 0) {
        return;
      }

      const prevNode = body[index - 1];

      if (!prevNode || !prevNode.loc) {
        return;
      }

      const linesBetween = node.loc.start.line - prevNode.loc.end.line;

      if (linesBetween < 2) {
        context.report({
          node,
          messageId: 'missingPadding',
          data: { keyword: node.type.toLowerCase() },
          fix: (fixer) => {
            return fixer.insertTextBefore(node, '\n');
          },
        });
      }
    };

    return {
      IfStatement: checkPadding,
      ForStatement: checkPadding,
      ForInStatement: checkPadding,
      ForOfStatement: checkPadding,
      WhileStatement: checkPadding,
      SwitchStatement: checkPadding,
      TryStatement: checkPadding,
      WithStatement: checkPadding,
    };
  },
};