editorSearch.es6

const contents = `
afder is bar and baz is {{biz}} {shouldnt find}{{but_this_should}}
{{blah}}
`;

const parseDatabaseFields = (input) => {
  const pattern = '\{\{(.*?)\}\}';
  const regex = new RegExp(pattern, 'gm');
  let match;
  const matches = [];
  while ((match = regex.exec(input)) !== null) {
    matches.push({
      name: match[0],
      value: match[1],
      startIndex: match.index,
      endIndex: match.index + match[0].length,
    });
  }
  return matches;
};

const selectionIsNextToDatabaseField = (selectionIndex, dbFields) =>
  dbFields
  .map(dbField => dbField.endIndex)
  .find(index => selectionIndex === (index + 1)) !== undefined;

console.log(parseDatabaseFields(contents));

console.log(selectionIsNextToDatabaseField(33, parseDatabaseFields(contents)));